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1.  Problems with tense marking in children with specific language impairment: not how but when
Many children with specific language impairment (SLI) have persisting problems in the correct use of verb tense, but there has been disagreement as to the underlying reason. When we take into account studies using receptive as well as expressive language tasks, the data suggest that the difficulty for children with SLI is in knowing when to inflect verbs for tense, rather than how to do so. This is perhaps not surprising when we consider that tense does not have a transparent semantic interpretation, but depends on complex relationships between inflections and hierarchically organized clauses. An explanation in terms of syntactic limitations contrasts with a popular morpho-phonological account, the Words and Rules model. This model, which attributes problems to difficulties with applying a rule to generate regular inflected forms, has been widely applied to adult-acquired disorders. There are striking similarities in the pattern of errors in adults with anterior aphasia and children with SLI, suggesting that impairments in appreciation of when to mark tense may apply to acquired as well as developmental disorders.
PMCID: PMC3866428  PMID: 24324242
specific language impairment; grammar; past tense; morphology; aphasia; inflections
2.  When words fail us: insights into language processing from developmental and acquired disorders
Acquired disorders of language represent loss of previously acquired skills, usually with relatively specific impairments. In children with developmental disorders of language, we may also see selective impairment in some skills; but in this case, the acquisition of language or literacy is affected from the outset. Because systems for processing spoken and written language change as they develop, we should beware of drawing too close a parallel between developmental and acquired disorders. Nevertheless, comparisons between the two may yield new insights. A key feature of connectionist models simulating acquired disorders is the interaction of components of language processing with each other and with other cognitive domains. This kind of model might help make sense of patterns of comorbidity in developmental disorders. Meanwhile, the study of developmental disorders emphasizes learning and change in underlying representations, allowing us to study how heterogeneity in cognitive profile may relate not just to neurobiology but also to experience. Children with persistent language difficulties pose challenges both to our efforts at intervention and to theories of learning of written and spoken language. Future attention to learning in individuals with developmental and acquired disorders could be of both theoretical and applied value.
PMCID: PMC3866430  PMID: 24324244
aphasia; dyslexia; specific language impairment; cognitive neuropsychology; connectionist models; development
3.  Preface
PMCID: PMC3866433  PMID: 24324247
4.  Autism, language and communication in children with sex chromosome trisomies
PMCID: PMC3182523  PMID: 20656736
5.  Which Neurodevelopmental Disorders Get Researched and Why?
PLoS ONE  2010;5(11):e15112.
There are substantial differences in the amount of research concerned with different disorders. This paper considers why.
Bibliographic searches were conducted to identify publications (1985–2009) concerned with 35 neurodevelopmental disorders: Developmental dyslexia, Developmental dyscalculia, Developmental coordination disorder, Speech sound disorder, Specific language impairment, Attention deficit hyperactivity disorder, Autistic spectrum disorder, Tourette syndrome, Intellectual disability, Angelman syndrome, Cerebral palsy, Cornelia de Lange syndrome, Cri du chat syndrome, Down syndrome, Duchenne muscular dystrophy, Fetal alcohol syndrome, Fragile X syndrome, Galactosaemia, Klinefelter syndrome, Lesch-Nyhan syndrome, Lowe syndrome, Marfan syndrome, Neurofibromatosis type 1, Noonan syndrome, Phenylketonuria, Prader-Willi syndrome, Rett syndrome, Rubinstein-Taybi syndrome, Trisomy 18, Tuberous sclerosis, Turner syndrome, Velocardiofacial syndrome, Williams syndrome, XXX and XYY. A publication index reflecting N publications relative to prevalence was derived.
The publication index was higher for rare than common conditions. However, this was partly explained by the tendency for rare disorders to be more severe.
Although research activity is predictable from severity and prevalence, there are exceptions. Low rates of research, and relatively low levels of NIH funding, characterise conditions that are the domain of a single discipline with limited research resources. Growth in research is not explained by severity, and was exceptionally steep for autism and ADHD.
PMCID: PMC2994844  PMID: 21152085
6.  Assessment of Cerebral Lateralization in Children using Functional Transcranial Doppler Ultrasound (fTCD)
PMCID: PMC3346060  PMID: 20972398
Neuroscience;  Issue 43;  functional transcranial Doppler ultrasound;  cerebral lateralization;  language;  child
7.  Developmental cognitive genetics: How psychology can inform genetics and vice versa
Developmental neuropsychology is concerned with uncovering the underlying basis of developmental disorders such as specific language impairment (SLI), developmental dyslexia, and autistic disorder. Twin and family studies indicate that genetic influences play an important part in the aetiology of all of these disorders, yet progress in identifying genes has been slow. One way forward is to cut loose from conventional clinical criteria for diagnosing disorders and to focus instead on measures of underlying cognitive mechanisms. Psychology can inform genetics by clarifying what the key dimensions are for heritable phenotypes. However, it is not a one-way street. By using genetically informative designs, one can gain insights about causal relationships between different cognitive deficits. For instance, it has been suggested that low-level auditory deficits cause phonological problems in SLI. However, a twin study showed that, although both types of deficit occur in SLI, they have quite different origins, with environmental factors more important for auditory deficit, and genes more important for deficient phonological short-term memory. Another study found that morphosyntactic deficits in SLI are also highly heritable, but have different genetic origins from impairments of phonological short-term memory. A genetic perspective shows that a search for the underlying cause of developmental disorders may be misguided, because they are complex and heterogeneous and are associated with multiple risk factors that only cause serious disability when they occur in combination.
PMCID: PMC2409179  PMID: 16769616
8.  Forty years on: Uta Frith's contribution to research on autism and dyslexia, 1966–2006
Uta Frith has made a major contribution to our understanding of developmental disorders, especially autism and dyslexia. She has studied the cognitive and neurobiological bases of both disorders and demonstrated distinctive impairments in social cognition and central coherence in autism, and in phonological processing in dyslexia. In this enterprise she has encouraged psychologists to work in a theoretical framework that distinguishes between observed behaviour and the underlying cognitive and neurobiological processes that mediate that behaviour.
PMCID: PMC2409181  PMID: 18038335
9.  Training understanding of reversible sentences: a study comparing language-impaired children with age-matched and grammar-matched controls
PeerJ  2014;2:e656.
Introduction. Many children with specific language impairment (SLI) have problems with language comprehension, and little is known about how to remediate these. We focused here on errors in interpreting sentences such as “the ball is above the cup”, where the spatial configuration depends on word order. We asked whether comprehension of such short reversible sentences could be improved by computerized training, and whether learning by children with SLI resembled that of younger, typically-developing children.
Methods. We trained 28 children with SLI aged 6–11 years, 28 typically-developing children aged from 4 to 7 years who were matched to the SLI group for raw scores on a test of receptive grammar, and 20 typically-developing children who were matched to the SLI group on chronological age. A further 20 children with SLI were given pre- and post-test assessments, but did not undergo training. Those in the trained groups were given training on four days using a computer game adopting an errorless learning procedure, during which they had to select pictures to correspond to spoken sentences such as “the cup is above the drum” or “the bird is below the hat”. Half the trained children heard sentences using above/below and the other half heard sentences using before/after (with a spatial interpretation). A total of 96 sentences was presented over four sessions. Half the sentences were unique, whereas the remainder consisted of 12 repetitions of each of four sentences that became increasingly familiar as training proceeded.
Results. Age-matched control children performed near ceiling (≥ 90% correct) in the first session and were excluded from the analysis. Around half the trained SLI children also performed this well. Training effects were examined in 15 SLI and 16 grammar-matched children who scored less than 90% correct on the initial training session. Overall, children’s scores improved with training. Memory span was a significant predictor of improvement, even after taking into account performance on training session 1. Unlike the grammar-matched controls, children with SLI showed greater accuracy with repeated sentences compared with unique sentences. Training did not improve children’s performance on a standardized test of receptive grammar.
Discussion. Overall, these results indicate that a subset of children with SLI perform well below ceiling on reversible sentences with three key words and simple syntactic structure. For these children, weak verbal short-term memory appears to impair comprehension of spoken sentences. In contrast to the general finding that rule-learning benefits from variable input, these children seem to do best if given repeated exposure to the same nouns used with a given sentence frame. Generalisation to other sentences using the same syntactic frame may be more effective if preceded by such item-specific learning.
PMCID: PMC4226637  PMID: 25392757
Specific language impairment; Child; Language; Intervention; Grammar; Receptive language; Comprehension; Verbal memory; Procedural learning; Speech and language therapy
10.  No population bias to left-hemisphere language in 4-year-olds with language impairment
PeerJ  2014;2:e507.
Background. An apparent paradox in the field of neuropsychology is that people with atypical cerebral lateralization do not appear to suffer any cognitive disadvantage, yet atypical cerebral lateralization is more common in children and adults with developmental language disorders. This study was designed to explore possible reasons for this puzzling pattern of results.
Methods. We used functional transcranial Doppler ultrasound (fTCD) to assess cerebral blood flow during language production in 57 four-year-olds, including 15 children who had been late-talkers when first seen at 20 months of age. We categorized cerebral lateralization as left, right or bilateral, and compared proportions with each type of laterality with those seen in a previously tested sample of children aged 6–16 years. We also compared language scores at 4 years for those with typical and atypical lateralization, and then looked at the association the opposite way: comparing those with typical or impaired language in terms of their cerebral lateralization.
Results. The distribution of types of cerebral lateralization was similar for 4-year-olds to that seen in older children. Overall, cerebral lateralization was not predictive of language level. However, for children who had language difficulties at 20 months and/or 4 years (N = 21), there was no population bias to left-hemisphere language activation, whereas children without language problems at either age showed a pronounced bias to left-sided language lateralization. Nevertheless, many children with right hemisphere language had no indications of language difficulties, confirming that atypical cerebral asymmetry is not a direct cause of problems.
Conclusions. We suggest that atypical lateralization at the individual level is not associated with language impairment. However, lack of lateralization at the population level is a marker of risk for language impairment, which could be due to genetic or non-genetic causes.
PMCID: PMC4137668  PMID: 25165624
Language impairment; Cerebral lateralization; Transcranial functional Doppler ultrasound; Child; Asymmetry
11.  Cerebral asymmetry and language development: cause, correlate or consequence?
Science (New York, N.Y.)  2013;340(6138):1230531.
In most people language is processed predominantly by the left hemisphere, but we don’t know how or why. A popular view is that developmental language disorders result from a poorly lateralized brain, but until recently evidence has been weak and indirect. Modern neuroimaging methods have made it possible to study normal and abnormal development of lateralized function in the developing brain and have confirmed links with language and literacy impairments. However, there is little evidence that weak cerebral lateralization has common genetic origins with language/literacy impairments. Our understanding of the association between atypical language lateralization and developmental disorders may benefit if we reconceptualise the nature of cerebral asymmetry to recognize its multidimensional nature and to take into account variation in lateralization over developmental time. Contrary to popular belief, cerebral lateralization may not be a highly heritable, stable characteristic of individuals; rather, weak lateralization may be a consequence of impaired language learning.
PMCID: PMC4031634  PMID: 23766329
12.  Sequence-specific Procedural Learning Deficits in Children with Specific Language Impairment
Developmental science  2014;17(3):352-365.
This study tested the procedural deficit hypothesis of specific language impairment (SLI) by comparing children’s performance in two motor procedural learning tasks and an implicit verbal sequence learning task. Participants were 7- to 11-year-old children with SLI (n= 48), typically-developing age-matched children (N = 20) and younger typically-developing children matched for receptive grammar (N = 28). In a serial reaction time task, the children with SLI performed at the same level as the grammar-matched children, but poorer than age-match controls in learning motor sequences. When tested with a motor procedural learning task that did not involve learning sequential relationships between discrete elements (i.e., pursuit rotor), the children with SLI performed comparably with age-matched children and better than younger grammar-matched controls. In addition, poor implicit learning of word sequences in a verbal memory task (Hebb effect) was found in the children with SLI. Together, these findings suggest that SLI might be characterized by deficits in learning sequence-specific information, rather than generally weak procedural learning.
PMCID: PMC4031743  PMID: 24410990
procedural learning; sequence learning; SLI
13.  A Spotlight on Preschool: The Influence of Family Factors on Children’s Early Literacy Skills
PLoS ONE  2014;9(4):e95255.
Phonological awareness, letter knowledge, oral language (including sentence recall) and rapid automatised naming are acknowledged within-child predictors of literacy development. Separate research has identified family factors including socio-economic status, parents’ level of education and family history. However, both approaches have left unexplained significant amounts of variance in literacy outcomes. This longitudinal study sought to improve prospective classification accuracy for young children at risk of literacy failure by adding two new family measures (parents’ phonological awareness and parents’ perceived self-efficacy), and then combining the within-child and family factors.
Pre-literacy skills were measured in 102 four year olds (46 girls and 56 boys) at the beginning of Preschool, and then at the beginning and end of Kindergarten, when rapid automatised naming was also measured. Family factors data were collected at the beginning of Preschool, and children’s literacy outcomes were measured at the end of Year 1 (age 6–7 years).
Children from high-risk backgrounds showed poorer literacy outcomes than low-risk students, though three family factors (school socio-economic status, parents’ phonological awareness, and family history) typically accounted for less Year 1 variance than the within-child factors. Combining these family factors with the end of Kindergarten within-child factors provided the most accurate classification (i.e., sensitivity = .85; specificity = .90; overall correct = .88).
Our approach would identify at-risk children for intervention before they began to fail. Moreover, it would be cost-effective because although few at-risk children would be missed, allocation of unnecessary educational resources would be minimised.
PMCID: PMC3994054  PMID: 24751691
14.  Children with Specific Language Impairment are not impaired in the acquisition and retention of Pavlovian delay and trace conditioning of the eyeblink response☆
Brain and Language  2013;127(3):428-439.
•We tested the integrity of small regions of the cerebellum and hippocampal formation in children with SLI.•Pavlovian delay conditioning engages elements of the procedural memory system.•Pavlovian trace conditioning engages procedural and declarative memory systems.•Children with Specific Language Impairment learned to delay and trace conditioning.•Brain regions engaged in eyeblink conditioning are normal in children with SLI.
Three converging lines of evidence have suggested that cerebellar abnormality is implicated in developmental language and literacy problems. First, some brain imaging studies have linked abnormalities in cerebellar grey matter to dyslexia and specific language impairment (SLI). Second, theoretical accounts of both dyslexia and SLI have postulated impairments of procedural learning and automatisation of skills, functions that are known to be mediated by the cerebellum. Third, motor learning has been shown to be abnormal in some studies of both disorders. We assessed the integrity of face related regions of the cerebellum using Pavlovian eyeblink conditioning in 7–11 year-old children with SLI. We found no relationship between oral language skills or literacy skills with either delay or trace conditioning in the children. We conclude that this elementary form of associative learning is intact in children with impaired language or literacy development.
PMCID: PMC3847270  PMID: 24139661
Specific Language Impairment; SLI; Pavlovian; Classical; Conditioning; Eyeblink; Delay; Trace; Cerebellum; Procedural
15.  Fine motor deficits in reading disability and language impairment: same or different?
PeerJ  2013;1:e217.
Several studies have found evidence of motor deficits in poor readers. There is no obvious reason for motor and literacy skills to go together, and it has been suggested that both deficits could be indicative of an underlying problem with cerebellar function and/or procedural learning. However, the picture is complicated by the fact that reading problems often co-occur with oral language impairments, which have also been linked with motor deficits. This raises the question of whether motor deficits characterise poor readers when language impairment has been accounted for – and vice versa. We considered these questions by assessing motor deficits associated with reading disability (RD) and language impairment (LI). A large community sample provided a subset of 9- to 10-year-olds, selected to oversample children with reading and/or language difficulties, to give 37 children with comorbid LI + RD, 67 children with RD only, 32 children with LI only, and 117 typically-developing (TD) children with neither type of difficulty. These children were given four motor tasks that taxed speed, sequence, and imitation abilities to differing extents. Different patterns of results were found for the four motor tasks. There was no effect of RD or LI on two speeded fingertip tapping tasks, one of which involved sequencing of movements. LI, but not RD, was associated with problems in imitating hand positions and slowed performance on a speeded peg-moving task that required a precision grip. Fine motor deficits in poor readers may be more a function of language impairment than literacy problems.
PMCID: PMC3845870  PMID: 24349898
Reading disability; Specific language impairment; Dyslexia; Motor; Imitation; Speed; Dexterity; Comorbidity
16.  Associations between Handedness and Cerebral Lateralisation for Language: A Comparison of Three Measures in Children
PLoS ONE  2013;8(5):e64876.
It has been known for many years that hand preference is associated with cerebral lateralisation for language, but the relationship is weak and indirect. It has been suggested that quantitative measures of differential hand skill or reaching preference may provide more valid measures than traditional inventories, but to date these have not been validated against direct measures of cerebral lateralisation. We investigated the associations of three different handedness assessments; 1) a hand preference inventory, 2) a measure of relative hand skill, and 3) performance on a reaching task; with cerebral lateralisation for language function as derived from functional transcranial Doppler ultrasound during a language production task, in a group of 57 typically developing children aged from 6 to 16 years. Significant correlations between cerebral lateralisation for language production and handedness were found for a short version of the inventory and for performance on the reaching task. However, confidence intervals for the correlations overlapped and no one measure emerged as clearly superior to the others. The best handedness measures accounted for only 8–16% of the variance in cerebral lateralisation. These findings indicate that researchers should not rely on handedness as an indicator of cerebral lateralisation for language. They also imply that lateralisation of language and motor functions in the human brain show considerable independence from one another.
PMCID: PMC3667815  PMID: 23738006
17.  The Genetic and Environmental Foundation of the Simple View of Reading in Chinese
PLoS ONE  2012;7(10):e47872.
PMCID: PMC3480450  PMID: 23112862
19.  Delayed Retention of New Word-Forms Is Better in Children than Adults Regardless of Language Ability: A Factorial Two-Way Study
PLoS ONE  2012;7(5):e37326.
Nonword repetition, the ability to retain and repeat unfamiliar sequences of phonemes is usually impaired in children with specific language impairment (SLI), but it is unclear whether this explains slow language learning. Traditional nonword repetition tests involve a single presentation of nonwords for immediate repetition. Here we considered whether rate of learning of novel phonological sequences was impaired when the same items were presented repeatedly.
Methodology/Principal Findings
Three complex nonwords were each presented for repetition five times in two sessions (A and B) separated by one hour. We studied both adults and children from (i) families with a child with SLI and (ii) families whose children did not have SLI. This gave a 2×2 design with familial SLI as one factor, and age (up to or above 18 years) as the other. Overall, participants from families with SLI were poorer at nonword repetition than their peers from typical-language families, and there was a trend for children with SLI to show less within-session learning than typically developing children. However, between-session retention, measured as the difference between the last trial from session 1 and the first trial of session 2, showed a significant age effect, η2 = .139, p = .004, regardless of family SLI status. Adult participants showed a decrease in score from the last trial of session A to the first trial of session B, whereas children maintained their level of performance, regardless of whether or not they had SLI.
Poor nonword repetition in SLI appears to reflect inadequate encoding of phonological information, rather than problems retaining encoded information. Furthermore, the nonword learning task is consistent with the notion of a sensitive period in language learning: Children show better retention over a delay for new phonological sequences than adults, regardless of overall level of language ability.
PMCID: PMC3353950  PMID: 22615979
20.  Does cerebral lateralization develop? A study using functional transcranial Doppler ultrasound assessing lateralization for language production and visuospatial memory
Brain and Behavior  2012;2(3):256-269.
In the majority of people, language production is lateralized to the left cerebral hemisphere and visuospatial skills to the right. However, questions remain as to when, how, and why humans arrive at this division of labor. In this study, we assessed cerebral lateralization for language production and for visuospatial memory using functional transcranial Doppler ultrasound in a group of 60 typically developing children between the ages of six and 16 years. The typical pattern of left-lateralized activation for language production and right-lateralized activation for visuospatial memory was found in the majority of the children (58%). No age-related change in direction or strength of lateralization was found for language production. In contrast, the strength of lateralization (independent of direction) for visuospatial memory function continued to increase with age. In addition, boys showed a trend for stronger right-hemisphere lateralization for visuospatial memory than girls, but there was no gender effect on language laterality. We tested whether having language and visuospatial functions in the same hemisphere was associated with poor cognitive performance and found no evidence for this “functional crowding” hypothesis. We did, however, find that children with left-lateralized language production had higher vocabulary and nonword reading age-adjusted standard scores than other children, regardless of the laterality of visuospatial memory. Thus, a link between language function and left-hemisphere lateralization exists, and cannot be explained in terms of maturational change.
PMCID: PMC3381631  PMID: 22741100
Cerebral lateralization; development; functional transcranial Doppler ultrasonography; language production; left hemisphere; right hemisphere; visuospatial memory
21.  Lateralised visual attention is unrelated to language lateralisation, and not influenced by task difficulty – A functional transcranial Doppler study
Neuropsychologia  2012;50(5-3):810-815.
Graphical abstract
► fTCD gives a reliable index of cerebral lateralisation for visuospatial attention. ► Task difficulty has no effect on the laterality index in the visuospatial paradigm. ► Visuospatial and language lateralisation are not correlated within subjects. ► The results challenge single-factor theories of hemispheric specialisation.
Historically, most theoretical accounts of hemispheric specialisation have proposed a single underlying factor that leads to left hemisphere language and right hemisphere visuospatial processing in the majority of people. More recently empirical evidence has started to challenge this view, suggesting lateralisation of language and visuospatial attention are independent. However, so far studies did not control for a possible confound, task difficulty. For this study, 20 healthy right-handed volunteers underwent functional laterality assessment using functional transcranial Doppler ultrasound (fTCD). We assessed laterality using both a word generation task and a novel variation of the visuospatial landmark task that can be adjusted along two dimensions of difficulty (temporal and spatial). The visuospatial laterality measures were highly intercorrelated and unaffected by task difficulty. Furthermore, there was no correlation between visuospatial and verbal lateralisation within individuals – neither qualitatively (in direction of lateralisation), nor quantitatively (in laterality index size). These results substantiate a growing body of evidence suggesting multiple independent biases leading to the hemispheric lateralisation of different cognitive domains, thus further questioning previously accepted models of laterality development and evolution.
PMCID: PMC3334833  PMID: 22285903
Cerebral laterality; Difficulty; Functional transcranial Doppler ultrasound (fTCD); Landmark task; Visuospatial attention; Verbal fluency; Word generation task
22.  dopOSCCI: A functional transcranial Doppler ultrasonography summary suite for the assessment of cerebral lateralization of cognitive function
Journal of Neuroscience Methods  2012;204(2-2):383-388.
► We present a new functional transcranial Doppler ultrasongraphy toolbox for Matlab. ► The basic features include multi-file summaries and laterality index calculation. ► Advanced features include behavioural and multi-session summaries. ► The toolbox is freely available under the GNU GPL license.
We present a description of a new software package, ‘dopOSCCI’, which summarises data from experimental studies where functional transcranial Doppler ultrasonography (fTCD) is used to compare hemispheric rates of blood flow in order to assess lateralization of a cognitive process. The software provides a graphical user interface to summarise analogue and digital data collected using Multi-Dop Doppler Ultrasound devices (DWL Multidop T2: manufacturer, DWL Elektronische Systeme, Singen, Germany). The unique aspects of dopOSCCI allow multi-file processing, multi-event marker processing, behavioural and multi-session summaries, image file data visualization, and tab-delimited output files which includes split-half, single-trial summaries and data quality variables. The Matlab based software is available under the GNU GPL license and can be accessed online at, the Oxford University DataBank.
PMCID: PMC3314978  PMID: 22120689
Functional transcranial Doppler ultrasonography; Imaging; Blood flow velocity; Methods; Matlab
23.  Co-localisation of abnormal brain structure and function in specific language impairment
Brain and Language  2012;120(3-4):310-320.
Graphical abstract
► Compared brain structure and function in SLI, unaffected siblings, and typical peers. ► More grey matter in SLI in the left inferior frontal cortex. ► Less grey matter in SLI in the right caudate nucleus and superior temporal cortex bilaterally. ► Functional activation was examined with an auditory covert naming task. ► Functionally, SLI had reduced activation of the left inferior frontal cortex and the superior temporal cortex bilaterally.
We assessed the relationship between brain structure and function in 10 individuals with specific language impairment (SLI), compared to six unaffected siblings, and 16 unrelated control participants with typical language. Voxel-based morphometry indicated that grey matter in the SLI group, relative to controls, was increased in the left inferior frontal cortex and decreased in the right caudate nucleus and superior temporal cortex bilaterally. The unaffected siblings also showed reduced grey matter in the caudate nucleus relative to controls. In an auditory covert naming task, the SLI group showed reduced activation in the left inferior frontal cortex, right putamen, and in the superior temporal cortex bilaterally. Despite spatially coincident structural and functional abnormalities in frontal and temporal areas, the relationships between structure and function in these regions were different. These findings suggest multiple structural and functional abnormalities in SLI that are differently associated with receptive and expressive language processing.
PMCID: PMC3315677  PMID: 22137677
Developmental disorders; Voxel-based morphometry; Functional magnetic resonance imaging; Language specialisation; Lateralisation
24.  Adult psychosocial outcomes of children with specific language impairment, pragmatic language impairment and autism
Background: The few studies that have tracked children with developmental language disorder to adulthood have found that these individuals experience considerable difficulties with psychosocial adjustment (for example, academic, vocational and social aptitude). Evidence that some children also develop autistic symptomatology over time has raised suggestions that developmental language disorder may be a high-functioning form of an autism spectrum disorder (ASD). It is not yet clear whether these outcomes vary between individuals with different subtypes of language impairment.
Aims: To compare the adult psychosocial outcomes of children with specific language impairment (SLI), pragmatic language impairment (PLI) and ASD.
Methods & Procedures: All participants took part in research as children. In total, there were 19 young adults with a childhood history of Specific Language Impairment (M age = 24;8), seven with PLI (M age = 22;3), 11 with high functioning ASD (M age = 21;9) and 12 adults with no history of developmental disorder (Typical; n = 12; M age = 21;6). At follow-up, participants and their parents were interviewed to elicit information about psychosocial outcomes.
Outcomes & Results: Participants in the SLI group were most likely to pursue vocational training and work in jobs not requiring a high level of language/literacy ability. The PLI group tended to obtain higher levels of education and work in ‘skilled’ professions. The ASD participants had lower levels of independence and more difficulty obtaining employment than the PLI and SLI participants. All groups had problems establishing social relationships, but these difficulties were most prominent in the PLI and ASD groups. A small number of participants in each group were found to experience affective disturbances. The PLI and SLI groups showed lower levels of autistic symptomatology than the ASD group.
Conclusions & Implications: The between-group differences in autistic symptomatology provide further evidence that SLI, PLI, and ASD are related disorders that vary along qualitative dimensions of language structure, language use and circumscribed interests. Childhood diagnosis showed some relation to adult psychosocial outcome. However, within-group variation highlights the importance of evaluating children on a case-by-case basis.
PMCID: PMC2835860  PMID: 19340628
specific language impairment; pragmatic language impairment; autism; longitudinal; psychosocial; outcome
25.  Qualitative aspects of developmental language impairment relate to language and literacy outcome in adulthood
Background: Developmental language disorder is a heterogeneous diagnostic category. Little research has compared the long-term outcomes of children with different subtypes of language impairment.
Aims: To determine whether the pattern of language impairment in childhood related to language and literacy outcomes in adulthood.
Methods & Procedures: Adults who took part in previous studies as children were traced. There were four groups of participants, each with a different childhood diagnosis: specific language impairment (SLI; n = 19, mean age at follow-up = 24;8), pragmatic language impairment (PLI; n = 7, mean age at follow-up = 22;3), autism spectrum disorder (ASD; n = 11; mean age at follow-up = 21;9), and no childhood diagnosis (typical; n = 12; mean age at follow-up = 21;6). Participants were administered a battery of language and literacy tests.
Outcomes & Results: Adults with a history of SLI had persisting language impairment as well as considerable literacy difficulties. Pragmatic deficits also appeared to develop over time in these individuals. The PLI group had enduring difficulties with language use, but presented with relatively intact language and literacy skills. Although there were some similarities in the language profile of the PLI and ASD groups, the ASD group was found to have more severe pragmatic deficits and parent-reported linguistic difficulties in conversational speech.
Conclusions & Implications: The pattern of deficits observed in different subtypes of developmental language disorder persists into adulthood. The findings highlight the importance of a wide-ranging clinical assessment in childhood, which may provide an indication of outcome in adulthood.
PMCID: PMC2892753  PMID: 19343569
specific language impairment; pragmatic language impairment; autism; language; literacy; outcome

Results 1-25 (54)


CENTENNIAL, Colo. (AP) — A police officer responding to the deadly Colorado theater shooting testified on Tuesday that he asked James Holmes twice whether he had an accomplice, but Holmes only looked at him and smiled.

Officer Justin Grizzle described the smile as “a self-satisfying offensive smirk” during a pretrial hearing over Holmes’ statements to police before he was read his Miranda rights.

They said Holmes didn’t resist when they told him first to raise his hands, then to lie on the ground.

Sweeney said that when he asked Holmes if there was another shooter, Holmes answered “No, it’s just me.”

Sweeney said officers couldn’t see through the tinted passenger side windows to detect whether anyone was inside, so they looked in through the open driver’s door. No one was inside.

“It was just chaos with everybody trying to figure out what was going on,” Sweeney said.

According to documents and testimony in the case, officers also asked Holmes questions about weapons and explosives. Roughly two hours would pass before the chaos subsided and detectives would read Holmes his rights – anything you say can be used against you.

Holmes’ lawyers argue that delay violated his constitutional rights and that anything he told the arresting officers should be barred from his trial.

Barring the use of Holmes’ statements would likely have a limited impact on his trial because his lawyers have acknowledged he was the shooter and the trial is expected to focus on whether or not he was legally insane at the time of the shooting.

Prosecutors are seeking the death penalty.

After the shooting, investigators say Holmes told officers that he had four guns and that bombs were rigged at his apartment to explode if anyone went inside.

Holmes was then driven to a police station where a detective again asked if anyone helped him. Sometime around 2:30 a.m. on July 21, a detective began reading Holmes his Miranda warning.

“There were many locations inside and outside of Theater 9 where other assailants could be hidden,” prosecutors wrote.

Officer: Holmes gave ‘self-satisfying’ smirk in Aurora


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5HTP. Enzyme. Like all catalysts, enzymes work by lowering the activation energy (Ea‡) for a reaction, thus dramatically increasing the rate of the reaction.

As a result, products are formed faster and reactions reach their equilibrium state more rapidly. Most enzyme reaction rates are millions of times faster than those of comparable un-catalyzed reactions. As with all catalysts, enzymes are not consumed by the reactions they catalyze, nor do they alter the equilibrium of these reactions. However, enzymes do differ from most other catalysts in that they are highly specific for their substrates. Enzymes are known to catalyze about 4,000 biochemical reactions.[3] A few RNA molecules called ribozymes also catalyze reactions, with an important example being some parts of the ribosome.[4][5] Synthetic molecules called artificial enzymes also display enzyme-like catalysis.[6] Enzyme activity can be affected by other molecules.

Etymology and history Structures and mechanisms Specificity "Lock and key" model.

Food fortification. Food fortification or enrichment is the process of adding micronutrients (essential trace elements and vitamins) to food.

Food fortification

It can be purely a commercial choice to provide extra nutrients in a food, or sometimes it is a public health policy which aims to reduce numbers of people with dietary deficiencies in a population. Diets that lack variety can be deficient in certain nutrients. Sometimes the staple foods of a region can lack particular nutrients, due to the soil of a region, or because of the inherent inadequacy of the normal diet.

Addition of micronutrients to staples and condiments can prevent large-scale deficiency diseases in these cases.[1] While it is true that both fortification and enrichment refer to the addition of nutrients to food, the true definitions do slightly vary. Food fortification was identified as the second strategy of four by the WHO and FAO to begin decreasing the incidence of nutrient deficiencies at the global level.[2] Types of Food Fortification[edit] Neurotransmitter. Most neurotransmitters are about the size of a single amino acid, but some neurotransmitters may be the size of larger proteins or peptides.

A neurotransmitter is available only briefly – before rapid deactivation – to bind to the postsynaptic receptors. Deactivation may occur due to: the removal of neurotransmitter by re-uptake into the presynaptic terminal; or degradative enzymes in the synaptic cleft. Nevertheless, short-term exposure of the receptor to neurotransmitter is typically sufficient for causing a postsynaptic response by way of synaptic transmission. In response to a threshold action potential or graded electrical potential, a neurotransmitter is released at the presynaptic terminal. Low level "baseline" release also occurs without electrical stimulation. Discovery[edit] Until the early 20th century, scientists assumed that the majority of synaptic communication in the brain was electrical.

Identification[edit] Types[edit] Major neurotransmitters: Actions[edit] Racetam. Racetams are a class of drugs that share a pyrrolidone nucleus.[1] Many, such as piracetam, but not all, are considered nootropics.

Some such as oxiracetam and phenylpiracetam are also stimulants. Others such as levetiracetam and seletracetam are anticonvulsants. Mechanism[edit] Adrenergic. Cholinergic. The N,N,N-trimethylethanolammonium cation, with an undefined counteranion, X− In general, the word choline refers to the various quaternary ammonium salts containing the N,N,N-trimethylethanolammonium cation.

Found in most animal tissues, choline is a primary component of the neurotransmitter acetylcholine and functions with inositol as a basic constituent of lecithin. It prevents fat deposits in the liver and facilitates the movement of fats into the cells. Nutraceutical. Nutraceutical, a portmanteau of the words “nutrition” and “pharmaceutical”, was coined in 1989 by Dr.

Stephen L. DeFelice, founder and chairman of the Foundation of Innovation Medicine (FIM) (Crawford, New Jersey).[1] The term is applied to products that range from isolated nutrients, dietary supplements and herbal products, specific diets and processed foods such as cereals, soups, and beverages. Regulation[edit] Anxiolytic. An anxiolytic (also antipanic or antianxiety agent)[1] is a medication or other intervention that inhibits anxiety.

This effect is in contrast to anxiogenic agents, which increase anxiety. Together these categories of psychoactive compounds or interventions may be referred to as anxiotropic compounds/agents. Some recreational drugs such as beverage alcohols (which contain ethanol) induce anxiolysis. Anxiolytic medications have been used for the treatment of anxiety and its related psychological and physical symptoms.

Corneliu E. Giurgea,[3][4] derived from the Greek words νους nous, or "mind", and τρέπειν trepein meaning to bend or turn.[5] Availability and prevalence[edit] Nootropics: their effects, their risks, and where to get them - Thinking in a nutshell. (With the perspectives of a user) Ten years ago I went on a quest to become an expert on coffee and to sample as many different ways of making it and as many different varieties that existed.

I tried everything from the French Press to the Coffee Siphon, Hawaiian Kona to Jamaican Blue Mountain. But unsatisfied with mere coffee, I went on a quest to find out how to use chemicals to enhance my mind. It had its roots in old high-school days when I'd bring a sixpack of Jolt cola to a computer-programming marathon: cramming together study halls and lunch breaks in my senior year. Emulsion. A.

Two immiscible liquids, not yet emulsified B. An emulsion of Phase II dispersed in Phase I C. The unstable emulsion progressively separates D. The surfactant (outline around particles) positions itself on the interfaces between Phase II and Phase I, stabilizing the emulsion IUPAC definition.


Day 6 from the CBC is a lively news magazine show that brings you a fresh and surprising take on the week. Think of the show as your weekly news cocktail, shaken and stirred. Host Brent Bambury brings his sharp mind, sense of humor, and charm to the program, honed after years of hosting everything from network television to daily radio.

Latest episodes from Day 6:

The latest food trends | asking candidates to step aside | Richard Dawkins on his new memoir | Lawrence Hill on the refugee crisis
Asking spies to quit the business | candidates looking to unseat party leaders in their ridings | a politician's survival guide for social media | clashes over gentrification | why extreme acts of altruism make some people uncomfortable
Affordable housing as an election issue |the Vatican's new astronomer | farmers ploughing election signs | a neuroscientist on studying deceased hockey players' brains | a discussion with Salman Rushdie on his new book

Brent Bambury

Brent Bambury has always had a deep connection to radio and was still a teenager when he launched his career at CBC working in Saint John, Halifax and Montreal. Decades later, with extensive radio and television journalism experience under his belt -- and still obsessed with creating new content.


John Valadez underscores the Chicano experience at MCASD

“Santa Ana Condition: John Valadez 1976 to 2011”

+Read Caption

As the show continues, the idea of “truth” is entirely unraveled in works that give “free rein … to the fantastical,” as Kanjo describes in the show’s catalog. There are large-scale, European-influenced allegory compositions and even a room full of colorful, imagined seascapes.

The stark differences in medium and content make the exhibition feel manic at times, but the diversity is more natural than a retrospective filled with work that looks eerily similar despite being created decades apart. Valadez is not the same person at 60 that he was at 25, so it follows that his work reflects his maturation.

“The thing that I see unifying so many of these vastly different works is that there’s a possibility of another way of seeing the world,” Kanjo said. “He’s not telling you what to think; he’s not didactic. He leaves just enough ambiguity for you to insert your own narrative.”


The Karoo Array Telescope (KAT-7) in South Africa, the pathfinder radio telescope for the $3 billion global Square Kilometre Array (SKA) project, has released its first results.

Imagine being the project scientist for a NASA experiment and getting an email telling you that a 3,100 lb. defunct spy satellite dating back to the Cold War might crash into your baby?

That's what happened to Julie McEnery of NASA's Fermi Gamma-ray Space Telescope,  which maps the highest-energy light in the universe, a year ago. When she checked her email on March 29th, 2012,  she had an automatically generated report from NASA's Robotic Conjunction Assessment Risk Analysis (CARA) saying that in about a week Fermi might be hit by Cosmos 1805.

A coronal mass ejection (CME) is when our sun sends billions of tons of solar particles into space. A CME can affect electronic systems in satellites and NASA recently saw three.

X-ray astronomy is only 50 years old but nothing shows the progress of the technology like a new view of a supernova scientists watched over a thousand years ago.

NASA's Hubble Space Telescope has found the farthest supernova so far. Supernova UDS10Wil, nicknamed SN Wilson after American President Woodrow Wilson, exploded more than 10 billion years ago.

SN UDS10Wil is a Type Ia supernovae. These beacons can be used as a yardstick for measuring cosmic distances. One of the debates surrounding Type Ia supernovae is the nature of the fuse that ignites them. This latest discovery adds credence to one of two competing theories of how they explode. Although preliminary, the evidence so far favors the explosive merger of two burned out stars; small, dim, and dense stars known as white dwarfs, the final state for stars like our Sun.

The first published results from the Alpha Magnetic Spectrometer (AMS) physics experiment on the International Space Station were announced today and though the result is the most precise measurement to date of the ratio of positrons to electrons in cosmic rays, we still have not caught our first glimpse into dark matter.

The AMS experiment, constructed at universities around the world and assembled at the European Organization for Nuclear Research (CERN), is the world's most precise detector of cosmic rays.  It was installed on the Space Station May 19th, 2011 after having been brought into orbit on the last flight of NASA's space shuttle Endeavour. To date it has measured over 30 billion cosmic ray events.

Today, the team released preliminary results based on the Planck observatory's first 15 months of data. They show that the universe is 100 million years older than we thought with more matter and less dark energy.

Decoding the Cosmos

The mission of the ESA Planck satellite is to observe the Universe of the past, seeing back in time, right after the Big Bang.

The image that the Planck scientists revealed today is that of the Universe as a child, dating back to about 380,000 years after the Big Bang, when its temperature was similar to that of the most external layer of a star today.

For a government that likes military action but not losing American lives, drones are the next big thing.   Drones have been, and will continue to be, used in more and more applications outside the military, including citizen surveillance and natural disaster research.

But military spending is what is driving optimization and the U.S. Department of Defense reports that drone accidents happen 50 times more often than mishaps involving human-operated aircraft. The U.S. Army and U.S. Marine Corps reported 43 mishaps that involved human factors issues associated with drone ground control workstations and technology during the years 2006 and 2007.


5 Branches of Philosophy

Written by Michael Vlach.

 Within philosophy there are five primary categories or branches:

1. Epistemology

Epistemology is the study of “knowledge.” Epistemology deals with the process by which we can know that something is true. It addresses questions such as:

--What can I know?

--How is knowledge acquired?

--Can we be certain of anything?

Within epistemology there are two important categories—rationalism and empiricism.

Rationalism stresses reason as the most important element in knowing. Rationalism holds that knowledge is gained primarily through the mind. It also asserts that we are born with innate ideas that precede any experiences we may have with our physical senses.

Empiricism, on the other hand, asserts that all our knowledge comes from our five senses. To use the terminology of the empiricist, John Locke, our minds are a “blank slate” at birth. Thus knowledge comes from our experiences.

2. Metaphysics

Metaphysics is the study of “reality.” More specifically it is the study of reality that is beyond the scientific or mathematical realms. The term “metaphysics” itself literally means “beyond the physical.” The metaphysical issues most discussed are the existence of God, the soul, and the afterlife.

3. Ethics

Ethics is the study of moral value, right and wrong. Ethics is involved with placing value to personal actions, decisions, and relations. Important ethical issues today include abortion, sexual morality, the death penalty, euthanasia, pornography, and the environment.

4. Logic

Logic is the study of right reasoning. It is the tool philosophers use to study other philosophical categories. Good logic includes the use of good thinking skills and the avoidance of logic fallacies.

5. Aesthetics

Aesthetics is the study of art and beauty. It attempts to address such issues as:

--What is art?

--What is the relationship between beauty and art?

--Are there objective standards by which art can be judged?

--Is beauty in the eye of the beholder?


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Description, Categories and Awards

The new international bestseller from the author of phenomenal Child 44 trilogy... The Farm If you refuse to believe me, I will no longer consider you my son. Daniel believed that his parents were enjoying a peaceful retirement on a remote farm in Sweden. But with a single phone call, everything changes. Your mother...she's not well, his father tells him. She's been imagining things - terrible, terrible things. She's had a psychotic breakdown, and been committed to a mental hospital. Before Daniel can board a plane to Sweden, his mother calls: Everything that man has told you is a lie. I'm not mad... I need the police... Meet me at Heathrow. Caught between his parents, and unsure of who to believe or trust, Daniel becomes his mother's unwilling judge and jury as she tells him an urgent tale of secrets, of lies, of a crime and a conspiracy that implicates his own father.
Daniel's parents have retired to Sweden. Though he has deferred travelling from London to spend some time with them at their new place, he has no reason to believe anything is wrong until he receives a call from his father, Chris, to let him know his mother, Tilde, is unwell and has been admitted to a mental hospital. Then, a call from Tilde, adamant that everything Chris is saying is untrue. 'The Farm' is about Daniel's attempts to unravel his parents' stories, as he tries to work out who to believe.

By telling the story largely at Tilde's pace, the reader is subject to discovering the story at the same time as Daniel. It is a multi-layered tale which hints at hidden menace for much of the story, without admitting the alleged crime Tilde is agitated about. Largely set in remote Sweden, the setting is a formidable presence in the story. I found this book absorbing and engaging - a crime thriller unlike any I have read in recent times. 'The Farm' deserves the accolades that have been heaped upon it.

The Farm is a terrific psychological thriller in the vein of Gillian Flynn's Gone Girl and Alice LaPlante's Turn of Mind. In The Farm, Smith gives us two potentially unreliable narrators: Tilde, who is convinced that her husband and the other men in her community are embroiled in a terrible criminal conspiracy, and her son Daniel, who must decide whether his mother is psychotic or his father a villain.

The story unfolds in roughly alternating chapters, as Tilde presents her "evidence" to Daniel and Daniel assesses the meaning of that evidence. Much of Tilde's testimony is gleaned from her diary; this approach, reminiscent of Gone Girl, immediately sucks the reader in, exposing us to the clues as Tilde encountered them. Tilde is a sympathetic character from the moment she arrives on the page; she tells her story so calmly and logically that the reader, just as Tilde herself, feels drawn to the inescapable conclusion that something is indeed rotten in the state of Sweden. And yet . . . what happened to Tilde in the summer of 1963? Is her personal experience tainting her perception of recent events? That is the question Daniel, and the reader, must resolve.

Compared to the fully fleshed-out character Smith has created in Tilde, Daniel is rather flat. He himself acknowledges that he is "weak," but that weakness seems to be as much a failing on Smith's part. While I can appreciate Smith's desire to juxtapose Tilde's strength against Daniel's milder personality, I felt that the only purpose Daniel ultimately served was as a foil to his mother, making his sudden decision to undertake his own investigation hard to swallow. Nevertheless, what he discovers in Sweden provides an unexpected payoff and a satisfying conclusion. I highly recommend The Farm to psychological thriller fans.

I received a free copy of The Farm through NetGalley in exchange for an honest review.

THE FARM opens "Until that phone call it had been an ordinary day." In fact, until the phone call from his father, Daniel had been living a very prosaic life. Even his hidden relationship with Mark, his lover, was based in large part on Daniel's ability to avoid conflict and court serenity. But with the phone call, Daniel discovers that the even-keeled childhood he experienced was all a sham. He finds himself caught between his father's insistence that his mother is an escaped lunatic and his mother's insistence that his father is part of a criminal ring. Almost all the rest of the book is built upon a potentially unreliable narrative presented by Daniel's mother, as his father attempts to track Daniel and his mum down.

Since his mum and dad moved to rural Sweden, his mum's original home, Daniel has had little communication with them. This has served his parents well, as they have been withholding their financial straits from him, and it has served him well as he has not found a way to come out to his parents. Mum's return to Sweden brought back memories from her childhood and early adolescence there, however, and contemporary events have mirrored those memories. Has Mum gone mad because of the circumstances, or are her accusations of Dad's involvement in a conspiracy accurate? As the book progresses, Daniel (along with the reader) is unsure. However, Smith does a tremendous job of smoothly transitioning from confusion to clarity by the end of the book. None of this is done through sleight of hand; rather, the interstices in the stories both Mum and Dad tell leave space for the reality to shine through.

Smith brings to life a rough rural Sweden where trolls still make sense and men still have all the power. The woods seem almost alive, and it isn't beyond the realm of possibility that a family could provide for itself by farming, fishing, and hunting. In this setting, it's not hard to believe that the men would conspire to protect a dark secret or that a woman might go mad. Smith's scene setting makes the conflict that Daniel experiences, caught between his parents, entirely believable. The main characters are deeply and realistically complex. Some of the secondary characters, especially Daniel's lover Mark, are less well developed. But THE FARM is such a psychological thriller that living inside Mum's head, or Daniel's, is far more important than understanding the more ancillary characters.

I read this book in one sitting, and I think it might be hard to dip into and out of the narrative. THE FARM is a book that just begs the reader to keep going. The psychological narrative keeps one engaged, and the mostly short "chapters" propel the reader forward. Dinner waited, as I couldn't put the book down at the end.

This review first appeared at www.reviewingtheevidence.com.

Carpe Librum
Oh my goodness! I've been hanging out to read The Farm by Tom Rob Smith ever since I heard the premise:

Daniel's parents have retired to Sweden, and all seems well until he receives a call from his father.
"Your mother's not well. She's been imagining things - terrible, terrible things. She's had a psychotic breakdown, and has been committed to a mental hospital."

But then his mother rings to say: "I'm sure your father has spoken to you. Everything that man has told you is a lie. I'm not mad. I don't need a doctor. I need the police. I'm about to board a flight to London. Meet me at Heathrow." (Source: GoodReads).

Daniel then has to decide which of his parents to believe. I was instantly hooked by the premise, and instantly gripped by the plot as soon as I picked up the book.

In fact, there was so much tension in The Farm, that I actually exclaimed, out loud, twice! The first was when Daniel's Mum says the simple words: "I told him everything" and I instantly yelled out "NO!"

And the second was when it was clear Daniel had made his decision about which parent to believe (no spoilers though). Oh, and the ending too, so I guess that makes three out loud exclamations and luckily for me they all occurred at home.

The Farm is a mystery and psychological thriller, which is surprising given the content is not driven by action so much as learning the truth about what took place. The plot is tight and the tension is palpable, and I thoroughly enjoyed it and highly recommend it.

I was also pleased to learn the movie rights have been sold, hopefully it's not too long before we can watch The Farm on the big screen. Get it, read it now!

This was a very enjoyable book. I am not giving the review justice. I read it a month or so ago and am already foggy on the details. It was a quick read, and something I am glad to have given my time. The story structure was wonderful. I recommended the book to my mom and she devoured it just as quickly. It was a fun read, you won’t want to put down – at least I didn't.

Book trailer for The Farm the new novel from Tom Rob Smith--author of the phenomenal Child 44 trilogy


Book Features Archive

Greece: A Short History of a Long Story presents a comprehensive overview of the history of Greece by exploring the continuity of Greek culture from its Neolithic origins to the modern era.

Serious and silly, unifying and polarizing, presidential elections have become events that Americans love and hate. Today's elections cost billions of dollars and consume the nation's attention for months, filling television airwaves and online media with endless advertising and political punditry, often heated, vitriolic, and petty. Yet presidential elections also provoke and inspire mass engagement of ordinary citizens in the political system.

For the Makahs, a tribal nation at the most northwestern point of the contiguous United States, a deep relationship with the sea is the locus of personal and group identity. Unlike most other indigenous tribes whose lives are tied to lands, the Makah people have long placed marine space at the center of their culture, finding in their own waters the physical and spiritual resources to support themselves.

In the late 1960s and early 1970s hundreds of thousands of white middle-class American youths suddenly became hippies. This short overview of the hippie social movement in the United States examines the movement's beliefs and practices, including psychedelic drugs, casual sex, and rock music, as well as the phenomena of spiritual seeking, hostility to politics, and communes. W. J. Rorabaugh synthesizes how hippies strived for authenticity, expressed individualism, and yearned for community.

Though best known for aircraft and aerospace technology, Boeing has invested significant time and money in the construction and promotion of its corporate culture. Boeing’s leaders, in keeping with the standard of traditional American social norms, began to promote a workplace culture of a white, heterosexual family model in the 1930s in an attempt to provide a sense of stability for their labor force during a series of enormous political, social, and economic disruptions.

The Rising Tide of Color challenges familiar narratives of race in American history that all too often present the U.S. state as a benevolent force in struggles against white supremacy, especially in the South. Featuring a wide range of scholars specializing in American history and ethnic studies, this powerful collection of essays edited by Moon-Ho Jung highlights historical moments and movements on the Pacific Coast and across the Pacific to reveal a different story of race and politics. From labor and anticolonial activists around World War I and multiracial campaigns by anarchists and communists in the 1930s to the policing of race and sexuality after World War II and transpacific movements against the Vietnam War, The Rising Tide of Color brings to light histories of race, state violence, and radical movements that continue to shape our world in the twenty-first century.

From the time of the Crimean War through the fall of the Tsar, the question of what to do about the Russian empire's large Muslim population was a highly contested issue among educated Russians both inside and outside the government. As formulated in the 19th and early 20th centuries, the Muslim Question comprised a complex set of ideas and concerns that centered on the problems of reimagining and governing the tremendously diverse Russian empire in the face of the challenges presented by the modernizing world.

In their quest for greater political participation within shifting imperial fields—from Spanish (1850s–1898) to US rule (1898-)—Puerto Ricans struggled to shape and contain conversations about race. In so doing, they crafted, negotiated, and imposed on others multiple forms of silences while reproducing the idea of a unified, racially mixed, harmonious nation. Silencing Race explores the ongoing, constant racialization of Puerto Rican workers to explore the 'class-making' of race.

Dread and enchantment haunt twentieth-century Dutch Indies and Indonesian literature, but Laurie Sears suggests that these literary works can bring ineffable experiences of trauma into narrative form.


Cardiac Arrest

DNR orders often do not align with poor prognosis

Although do-not-resuscitate (DNR) orders after in-hospital cardiac arrest were generally aligned with patients' likelihood of favorable neurological survival, almost two-thirds of patients with the worst prognosis did not ...

Sep 22, 2015
popularity7 comments 0

Fewer patients die at fully accredited hospitals

For the first time, researchers from Aarhus University, Aarhus University Hospital and the Region of Southern Denmark can now demonstrate an association between level of hospital accreditation and the mortality rate among ...

Sep 24, 2015
popularity7 comments 0

This text uses material from Wikipedia licensed under CC BY-SA

Latest Spotlight News

Neuropeptide may be real cause of migraines

A pair of researchers, one with New York University College of Dentistry in New York, the other with King's College in the U.K. has found that a neuropeptide may be responsible for the onset of migraines. In their paper published ...

Elephants provide big clue in fight against cancer

Carlo Maley spends his time pondering pachyderms—and cactuses and whales, and a wide array of non-human species—all in pursuit of the answer to this question: Why do some life forms get cancer while others do not?

Researchers test the brain's number sense perception

Number sense hypothesis holds that the intuitive understanding of numbers is a primary visual property, like color sense or physical orientation. In nature, this refers not to any ability to count, but to visually sense the ...

Researchers build a digital piece of brain

If you want to learn how something works, one strategy is to take it apart and put it back together again. For 10 years, a global initiative called the Blue Brain Project—hosted at the Ecole Polytechnique Federale de Lausanne ...


One of the primary pioneering theorists on apocalyptic global warming is Guenther Schwab (1902-2006), an Austrian Nazi.[i] In 1958, Schwab wrote a fictional novel built off of Goethe’s (1749-1832) Faustian religious play entitled “Dance with the Devil.” While a few scientists since the late 1800’s had contemplated the possibility of minor global warming coming from industrial pollution, Schwab used Goethe’s dramatic approach to convert the theory into an apocalyptic crisis. The book outlines many looming environmental emergencies, including anthropogenic global warming. Guenther Schwab’s very popular novel was an apocalyptic game changer. By the early 1970’s, it had been translated into several languages and had sold over a million copies.

The success of Schwab’s book helped him to establish an international environmental organization called “The World League for the Defense of Life.” Not surprisingly, Werner Haverbeck, former Hitler Youth member and Nazi environmental leader of the Reich’s League for Folk National Character and Landscape, later became the chairman of Schwab’s organization. In 1973, Haverbeck blamed the environmental crisis in Germany on American capitalism. It was an unnatural colonial import that had infected Germany like a deadly foreign body.

Continue reading →


person: the grammatical category which indicates whether a nominal is or includes the speaker and/or hearer. The speaker is traditionally called "first person", the hearer is called "second person", and anyone or anything which is neither speaker or hearer is called "third person". The pronoun "me" is a first person pronoun, and the verb "is" is a third person verb, because its subject is neither speaker nor hearer. If a group includes the speaker, it is first person plural; if it includes the hearer but not the speaker, it is second person plural; if it includes neither speaker nor hearer, it is third person plural. So, "they" is a third person plural pronoun, and the phrase "you all came" is second person plural. [Spanish: persona]


Original Link: http://www.anandtech.com/show/5847/answered-by-the-experts-heterogeneous-and-gpu-compute-with-amds-manju-hegde

AMD’s Manju Hegde is one of the rare folks I get to interact with who has an extensive background working at both AMD and NVIDIA. He was one of the co-founders and CEO of Ageia, a company that originally tried to bring higher quality physics simulation to desktop PCs in the mid-2000s. In 2008, NVIDIA acquired Ageia and Manju went along, becoming NVIDIA’s VP of CUDA Technical Marketing. The CUDA fit was a natural one for Manju as he spent the previous three years working on non-graphics workloads for highly parallel processors. Two years later, Manju made his way to AMD to continue his vision for heterogeneous compute work on GPUs. His current role is as the Corporate VP of Heterogeneous Applications and Developer Solutions at AMD.

Given what we know about the new AMD and its goal of building a Heterogeneous Systems Architecture (HSA), Manju’s position is quite important. For those of you who don’t remember back to AMD’s 2012 Financial Analyst Day, the formalized AMD strategy is to exploit its GPU advantages on the APU front in as many markets as possible. AMD has a significant GPU performance advantage compared to Intel, but in order to capitalize on that it needs developer support for heterogeneous compute. A major struggle everyone in the GPGPU space faced was enabling applications that took advantage of the incredible horsepower these processors offered. With AMD’s strategy closely married to doing more (but not all, hence the heterogeneous prefix) compute on the GPU, it needs to succeed where others have failed.

The hardware strategy is clear: don’t just build discrete CPUs and GPUs, but instead transition to APUs. This is nothing new as both AMD and Intel were headed in this direction for years. Where AMD sets itself apart is that it is willing to dedicate more transistors to the GPU than Intel. The CPU and GPU are treated almost as equal class citizens on AMD APUs, at least when it comes to die area.

The software strategy is what AMD is working on now. AMD’s Fusion12 Developer Summit (AFDS), in its second year, is where developers can go to learn more about AMD’s heterogeneous compute platform and strategy. Why would a developer attend? AMD argues that the speedups offered by heterogeneous compute can be substantial enough that they could enable new features, usage models or experiences that wouldn’t otherwise be possible. In other words, taking advantage of heterogeneous compute can enable differentiation for a developer.

In advance of this year’s AFDS, Manju agreed to directly answer your questions about heterogeneous compute, where the industry is headed and anything else AMD will be covering at AFDS. Today we have those answers.

How Fusion and HSA Differ

First and foremost, AMD has been down the GPGPU path before with Fusion. Can you explain how HSA is different?

Existing APIs for GPGPU are not the easiest to use and have not had widespread adoption by mainstream programmers. In HSA we have taken a look at all the issues in programming GPUs that have hindered mainstream adoption of heterogeneous compute and changed the hardware architecture to address those. In fact the goal of HSA is to make the GPU in the APU a first class programmable processor as easy to program as today's CPUs. In particular, HSA incorporates critical hardware features which accomplish the following:

1. GPU Compute C++ support: This makes heterogeneous compute access a lot of the programming constructs that only CPU programmers can access today

2. HSA Memory Management Unit: This allows all system memory is accessible by both CPU or GPU, depending on need. In today's world, only a subset of system memory can be used by the GPU.

3. Unified Address Space for CPU and GPU: The unified address space provides ease of programming for developers to create applications. By not requiring separate memory pointers for CPU and GPU, libraries can simplify their interfaces

4. GPU uses pageable system memory via CPU pointers: This is the first time the GPU can take advantage of the CPU virtual address space. With pageable system memory, the GPU can reference the data directly in the CPU domain. In all prior generations, data had to be copied between the two spaces or page-locked prior to use

5. Fully coherent memory between CPU & GPU: This allows for data to be cached in the CPU or the GPU, and referenced by either. In all previous generations GPU caches had to be flushed at command buffer boundaries prior to CPU access. And unlike discrete GPUs, the CPU and GPU share a high speed coherent bus

6. GPU compute context switch and GPU graphics pre-emption: GPU tasks can be context switched, making the GPU in the APU a multi-tasker. Context switching means faster application, graphics and compute interoperation. Users get a snappier, more interactive experience. As UI's are becoming increasing more touch focused, it is critical for applications trying to respond to touch input to get access to the GPU with the lowest latency possible to give users immediate feedback on their interactions. With context switching and pre-emption, time criticality is added to the tasks assigned to the processors. Direct access to the hardware for multi-users or multiple applications are either prioritized or equalized

As a result, HSA is a purpose designed architecture to enable the software ecosystem to combine and exploit the complementary capabilities of CPUs (sequential programming) and GPUs (parallel processing) to deliver new capabilities to users that go beyond the traditional usage scenarios. It may be the first time a processor company has made such significant investment primarily to improve ease of programming!

In addition on an HSA architecture the application codes to the hardware which enables user mode queueing, hardware scheduling and much lower dispatch times and reduced memory operations. We eliminate memory copies, reduce dispatch overhead, eliminate unnecessary driver code, eliminate cache flushes, and enable GPU to be applied to new workloads. We have done extensive analysis on several workloads and have obtained significant performance per joule savings for workloads such as face detection, image stabilization, gesture recognition etc…

Finally, AMD has stated from the beginning that our intention is to make HSA an open standard, and we have been working with several industry partners who share our vision for the industry and share our commitment to making this easy form of heterogeneous computing become prevalent in the industry. While I can't get into specifics at this time, expect to hear more about this in a few weeks at the AMD Fusion Developer Summit (AFDS).

So you see why HSA is different and why we are excited :)

I haz questions by B3an

Could an OS use GPU compute in the future to speed up everyday tasks, apart from the usual stuff like the UI? What possible tasks would this be? And is it possible we'll see this happen within the next few years?

Yes, definitely. OSes are moving towards providing some base functionality in terms of security, voice recognition, face detection, biometrics, gesture recognition, authentication, some core database functionality. All these benefit significantly from the optimizations in HSA described above. With the industry support we are building this should happen in the next few years.

Are you excited about Microsofts C++ Accelerated Massive Parallelism (AMP)? Do you think we'll see a lot more software using GPU compute now that Visual Studio 11 will include C++ AMP support?

We see C++amp as a great alternative to OpenCL. Both OpenCL and C++amp provide a method for utilizing the underlying GPU compute infrastructure, each with its own benefits. AMD realizes that different class of programmers may have different language preferences, so we will support both languages with the same level of quality, in order to serve our developer community better. C++AMP is a small delta to C++ and as such will appeal to many mainstream programmers and with Microsoft's support be able to reach a vast audience. So yes, we expect to see a lot more software using heterogeneous compute through this direction.

Do you expect the next gen consoles to make far more use of GPU compute?

Cannot comment further on this since these are products being brought forward by other companies.

Question by mrdude

The recent Kepler design has shown that there might be a chasm developing between how AMD and nVidia treat desktop GPUs. While GCN showed that it can deliver both fantastic compute performance (particularly on supported openCL tasks), it also weighs in heavier than Kepler and lags behind in terms of gaming performance. The added vRAM, bus width and die space for the 7970 allow for greater compute performance but at a higher cost; is this the road ahead and will this divide only further broaden as AMD pushes ahead? I guess what I'm asking is: Can AMD provide both great gaming performance as well as compute without having to sacrifice by increasing the overall price and complexity of the GPU?

Yes. You will see our future products continue to balance great gaming and compute performance.

It seems to me that HSA is going to require a complete turnaround for AMD as far as how they approach developers. Personally speaking, I've always thought of AMD as the engineers in the background who did very little to reach out and work with developers, but now in order to leverage the GPU as a compute tool in tasks other than gaming it's going to require a lot of cooperation with developers who are willing to put in the extra work. How is AMD going about this? and what apps will we see being transitioned into GPGPU in the near future?

Things have changed J. AMD has a team focused on developer solutions and outreach. This team drives the definition and deployment of tools, libraries, SDKs to the developer ecosystem including enablement content such as blogs, white papers and webinars. In addition, AMD works with key developers and also contributes to prominent open source code bases to promote GPU compute. The launch of the 2nd Generation AMD A-Series "Trinity" APU includes numerous applications that use the GPU for compute acceleration – Photoshop CS6, Winzip, x264/Handbrake, GIMP to name a prominent few. There are more plans in the works to reach out to developers and make it easy for them to extract the most from HSA platforms.

Offloading FP-related tasks to the GPU seems like a natural transition for a type of hardware that already excels in such tasks, but was HSA partly the reason for the single FPU in a Bulldozer module compared to the 2 ALUs?

We constantly evaluate the tradeoff of where to add compute execution resources. It is more expensive to add more computation resources in the CPU core since CPU vector execution resource are typically clocked higher, have multi-ported register files, support out-of-execution for latency hiding, etc. That said, the Bulldozer FPU does include support for new FMAC instructions and higher clock rate. So we really are investing in both CPU and GPU.

Is AMD planning to transition into an 'All APU' lineup for the future, from embedded to mobile to desktop and server?

AMD is all about meeting customer needs. We already have APUs for embedded, mobile (tablet and notebook) and desktop, and will address APUs for server as we continue to monitor what the market and customer needs are. In fact, we already have some partners incorporating APUs into server designs, one of which is Penguin Computing who is keynoting AFDS…

OpenCL by A5

What is AMD doing to make OpenCL more pleasant to work with?

Some of the initiatives that AMD has already driven are:
- Improved Debugger and Profiler (Visual Studio plugin, Standalone Eclipse, Linux)
- Static C++ interface (APP SDK 2.7)
- Extended tools thru MCW (PPA, GMAC, TM)
- OpenCL Book, Programming Guide (US, India, China editions)
- University course kit
- Webinars (Various topics)
- Online self-training material
- Hands-on tutorial, content in AFDS
- Moderated OpenCL forum
- OpenCL Training and Services Partners
- OpenCL acceleration of major Open Source codebases
- Aparapi to enable and ease Java users in using OpenCL

Questions by ltcommanderdata

WinZip and AMD have been promoting their joint venture in implementing OpenCL hardware accelerated compression and decompression. Owning an AMD GPU I appreciate it. However, it's been reported that WinZip's OpenCL acceleration only works on AMD CPUs. What is the reasoning behind this? Isn't it hypocritical, given AMD's previous stance against proprietary APIs, namely CUDA, that AMD would then support development of a vendor specific OpenCL program?

The OpenCL version of Winzip has been optimized on AMD GPUs and achieves significant performance gains. While OpenCL is not vendor specific optimizations on any application are essentially vendor specific since they depend on the microarchitecture of eachvendor. We worked closely with Winzip to get these optimizations in. We have the most mature OpenCL implementation currently and even then we just managed to get the QA done before WinZip's launch date. I am sure that they will be coming out with OpenCL optimized versions on Intel and Nvidia soon -- you should ask them). That is in fact the beauty of OpenCL – one code base gives functional portability across vendor platforms and optimizations are the only components that need to be scheduled. So yes this is in line with our embrace of open and industry standards.

This may be related to the above situation. Even with standardized, cross-platform, cross-vendor APIs like OpenCL, to get the best performance, developers would need to do vendor specific, even device generation within a vendor specific optimizations. Is there anything that can be done whether at the API level, at the driver level or at the hardware level to achieve the write-once, run-well anywhere ideal?

Device specific optimizations will always have a beneficial impact on performance. This is true even with CPUs. While differences between GPUs are more dramatic, this is due to the fact that today's GPUs are designed to excel at graphics while compute is a secondary consideration. Reluctance to spend more chip area on compute results in having many device specific performance "cliffs". For example, VLIW instructions, 64 thread wavefronts, and the need for coalesced accesses to memory. As GPUs are increasingly used for compute, and as it becomes possible to add yet more transistors, these "cliffs" will continue to disappear. Advances in compilers will also help.

Comparing the current implementations of on-die GPUs, namely AMD Llano and Intel Sandy Bridge/Ivy Bridge, it appears that Intel's GPU is more tightly integrated with CPU and GPU sharing the last level cache for example. Admittedly, I don't believe CPU/GPU data sharing is exposed to developers yet and only available to Intel's driver team for multimedia operations. Still, what are the advantages and disadvantages of allowing CPUs and GPUs to share/mix data? I believe memory coherency is a concern. Is data sharing the direction that things are eventually going to be headed?

For some workloads we expect data sharing between the CPU and GPU. In many cases the data being shared is quite large – for example a single frame of HD video with 4bytes/pixel is 8MB of data, and many algorithms are dealing with multiple frames of video so even seemingly large shared caches are not effective at capturing real-world working sets. We see clear advantages from CPU/GPU shared address spaces (same page tables) and high-bandwidth memory access from both devices.

As a follow up, it looks like the just released Trinity brings improved CPU/GPU data sharing as per question 3 above. Maybe you could compare and contrast Trinity and Ivy Bridge's approach to data sharing and give an idea of future directions in this area?

See above.

Related to the above, how much is CPU<>GPU communications a limitation for current GPGPU tasks? If this is a significant bottleneck, then tightly integrated on-die CPU/GPUs definitely show their worth. However, the amount of die space that can be devoted to an IGP is obviously more limited than what can be done with a discrete GPU. What can then be done to make sure the larger computational capacity of discrete GPUs isn't wasted doing data transfers? Is PCIe 3.0 sufficient? I don't remember if memory coherency was adopted for the final PCIe 3.0 spec, but would a new higher speed bus, dedicated to coherent memory transfers between the CPU and discrete GPU be needed?

For some applications, the CPU/GPU communication is so severe a limitation that it eliminates the gains from using the GPU. (For other algorithms, the communication is small or can be overlapped and the GPU can be used quite effectively). PCIe3.0 helps for large-block data transfers. Inherently though discrete GPUs will continue to provide higher peak computation capabilities (since the entire die is dedicated to GPU) but less tightly integrated than what can be achieved with an APU.

In terms of gaming, when GPGPU began entering consumer consciousness with the R500 series, GPGPU physics seemed to be the next big thing. Now that highly programmable GPUs are common place and the APIs have caught up, mainstream GPGPU physics is no where to be found. It seems the common current use cases for GPGPU in games is to decompress textures and to do ambient occlusion. What happened to GPGPU physics? Did developers determine that since multi-core CPUs are generally underutilized in games, there is plenty of room to expand physics on the CPU without having to bother with the GPU? Is GPGPU physics coming eventually? I could see concerns about contention between running physics and graphics on the same GPU, but given most CPUs are coming integrated with a GPGPU IGP anyways, the ideal configuration would be a multi-core CPU for game logic, an IGP as a physics accelerator, and a discrete GPU for graphics.

GPUs can run physics just fine. The problem with GPU physics is scaling. Unlike graphics, which easily scales across a wide range of hardware capabilities (eg: by changing resolution, using antialiasing, and changing texture resolution), it is very difficult to scale simulation compute requirements. Game programmers and artists must do a lot of extra work to take advantage of increased simulation capability, which they are reluctant to do, since they are usually happy to target lowest common denominator (consoles). This will continue to be the case until tools and runtimes are available which allow artists to create scalable physics content with little to no additional effort. HSA is an ideal architecture for running physics.

Latency and overhead by GullLars

Will the GPGPU acceleration mainly improve embarrassingly parallel and compute bandwidth constrained applications, or will it also be able to accelerate smaller pieces of work that are parallel to a significant degree.

Hitherto workloads with a significant amount of data parallel components only could benefit from heterogeneous compute. However since with HSA APUs the communication between GPU and CPU is no longer subject to unnecessary copies, no cache flushes are automatically invoked, and the optimization of the runtime and driver stacks greatly reduces the dispatch latency, the type and number of workloads that are benefited from heterogeneous compute are greatly increased.

And what is the latency associated with branching off and running a piece of code on the parallel part of the APU? (f.ex. as a method called by a program to work on a large set of independent data in parallel)

Different on different products

Change starts with you by Tanclearas

Although I do agree that there are many opportunities for HSA, I am concerned that AMD's own efforts in using heterogeneous computing have been half-baked. The AMD Video Converter has a smattering of conversion profiles, lacks any user-customizable options (besides a generic "quality" slider), and hasn't seen any update to the profiles in a ridiculously long time (unless there were changes/additions within the last few months).

AMD recognizes that heterogeneous compute requires specific and new measures to ease developer adoption. To this end AMD is adopting the strategy of delivering domain-specific SDKs and providing optimized sample applications. These serve as reference code to ease the developer's job of extracting performance especially for targeted and common use cases. APP SDK is an example - stay tuned for more

It is no secret that Intel has put considerable effort into compiler optimizations that required very little effort on the part of developers to take advantage of. AMD's approach to heterogeneous computing appears simply to wait for developers to do all the heavy lifting.

The question therefore is, when is AMD going to show real initiative with development, and truly enable developers to easily take advantage of HSA? If this is already happening, please provide concrete examples of such. (Note that a 3-day conference that also invites investors is hardly a long-term, on-going commitment to improvement in this area.)

Just to clarify, HSA is not available today. We outlined our roadmap for the future of APUs last year at AFDS, which included the evolution of HSA. Most of the HSA features will be available on our 2013 and 2014 platforms. We are going to announce the schedule for availability of our HSA software stack, our tools and the library plan at AFDS. AFDS is a continued forum where we will bring together software developers to interact with us and our partners to let them know the direction of our platforms in the future. The fact that investors attend does not detract from the fact that it is targeted primarily at software developers. The overwhelming majority of presentations and talks are directed at software developers. Several key partners will be delivering keynotes at AFDS expressing their aligned view of heterogeneous computing including technical leaders from Adobe. Cloudera, Penguin Computing, Gaikai and SRS.

We have just announced the increasing gamut of software who support OpenCL on our platforms today. These include companies such as SONY, Adobe, Arcsoft, Winzip, Cyberlink, Corel, Roxio, and many, many others. We are confident all of them will be enthusiastic about supporting HSA.

In addition see the answer to the above question and what we are doing wrt making OpenCL easier to use.

Two questions by markstock

Mr. Hegde, I have two questions which I hope you will answer.

To your knowledge, what are the major impediments preventing developers from thinking about this new hierarchy of computation and begin programming for heterogenous architectures?

See my answer to the first question where I list the hardware features of HSA and the issues they solve. Those are all issues with today's heterogeneous compute models.

AMD clearly aims to fill a void for silicon with tightly-coupled CPU-like and GPU-like computational elements, but are they only targeting the consumer market, or will future hardware be designed to also appeal to HPC users?

Absolutely. We will be bringing HSA based APUs to the market in the near future and all the aspects of ease of programming and much greater performance per joule that HSA brings to the market will greatly benefit the HPC space. In fact, Penguin Computing, is already implementing APUs in HPC server designs and will be sharing details on HPC heterogeneous compute at AFDS during their keynote.

When will the software catch up? by Loki726

AMD Fellow Mike Mantor has a nice statement that I believe captures the core difference between GPU and CPU design.

"CPUs are fast because they include hardware that automatically discovers and exploits parallelism (ILP) in sequential programs, and this works well as long as the degree of parallelism is modest. When you start replicating cores to exploit highly parallel programs, this hardware becomes redundant and inefficient; it burns power and area rediscovering parallelism that the programmer explicitly exposed. GPUs are fast because they spend the least possible area and energy on executing instructions, and run thousands of instructions in parallel."

Notice that nothing in here prevents a high degree of interoperability between GPU and CPU cores.

When will we see software stacks catch up with heterogeneous hardware? When can we target GPU cores with standard languages (C/C++/Objective-C/Java), compilers(LLVM, GCC, MSVS), and operating systems (Linux/Windows)? The fact that ATI picked a different ISA for their GPUs than x86 is not an excuse; take a page out of ARM's book and start porting compiler backends.

AMD is addressing this via HSA. HSA addresses these fundamental points by introducing an intermediate layer (HSAIL) that insulates software stacks from the individual ISAs. This is a fundamental enabler to the convergence of SW stacks on top of HC.

Unless the install base is large enough, the investment to port *all* standard languages across to an ISA is forbiddingly large. Individual companies like AMD are motivated but can only target a few languages at a time. And the software community is not motivated if the install base is fragmented. HSA breaks this deadlock by providing a "virtual ISA" in the form of HSAIL that unifies the view of HW platforms for SW developers. It is important to note that this is not just about functionality but preserves performance sufficiently to make the SW stack truly portable across HSA platforms

Why do we need new languages for programming GPUs that inherit the limitations of graphics shading languages? Why not toss OpenCL and DirectX compute, compile C/C++ programs, and launch kernels with a library call? You are crippling high level languages like C++-AMP, Python, and Matlab (not to mention applications) with a laundry list of pointless limitations.

AMD sees OpenCL as a critical and necessary step in the evolution of programming. Single-core programming evolved from assembly to C++ and Java. Starting with very few expert programmers doing close-to-metal coding, to a larger number of trained professionals driving products and finally making it easier for minimally trained programming masses to target CPUs. Symmetric multi-core programming went thru a similar trend thru pthreads to models like OpenMP and TBB.

Today, pioneered by experts who managed to write compute code within shaders, heterogeneous compute now has its first standard programming model in OpenCL. AMD introduced Aparapi that provides Java developers an easy way to access GPU compute. C++ AMP is the first instance of the natural next step in this evolution, i.e. extensions of existing programming models to target GPU compute and thus bringing in the (large) community adoption. AMD will strongly support this expansion into languages like Fortran, Python, Ruby, R, Matlab…

In addition, domain-specific libraries are also being targeted, e.g. OpenCV, x264, crypto++, to allow the programmer to focus on the job at hand, instead of the mechanics of obtaining performance. This is the fastest way to enable existing application code bases to leverage heterogeneous compute.

And of course, HSA is a key enabler of this next step since it expands the install base for SW developers to target via the portable performance it enables across various ISAs.

However, similar to assembly optimizations, AMD does see OpenCL continue to coexist with high-level programming to enable performance-critical developers to extract the most out of a particular platform.

Where's separable compilation? Why do you have multiple address spaces? Where is memory mapped IO? Why not support arbitrary control flow? Why are scratchpads not virtualized? Why can't SW change memory mappings? Why are thread schedulers not fair? Why can't SW interrupt running threads? The industry solved these problems in the 80s. Read about how they did it, you might be surprised that the exact same solutions apply.

- OpenCL 1.2 (supported by the upcoming AMD APP SDK 2.7) supports clCompileProgram and clLinkProgram.
- HSA MMU enables a shared address space between CPU and GPU
- HSAIL supports more flexible control flow.
- SI-based GPUs include high-performance read/write caches which effectively can be virtualized.
- Future AMD APUs will support HW context switching, including ability for SW to interrupt running threads

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