Man [previously] was conscious of himself only as member of a race, people, party, family, or corporation--only through some general category. In Italy this veil first melted into air; an objective treatment and consideration of the state and of all things of this world became possible. The subjective side at the same time asserted itself with corresponding emphasis; man became a spiritual individual, and recognized himself as such. (Butterfield, p.10)
In Burckhardt's formulation, the individual was seen in distinction from the group. But in the exhibition what we often view are individuals portrayed as the preeminent and exemplary representatives of groups; the men and women are depicted as distinguished members of a virtuosu and honored elite (p.10).
Recent studies show that dendritic spines are dynamic structures. Their rapid creation, destruction and shape-changing are essential for short- and long-term plasticity at excitatory synapses on pyramidal neurons in the cerebral cortex. The onset of long-term potentiation, spine-volume growth and an increase in receptor trafficking are coincident, enabling a ‘functional readout’ of spine structure that links the age, size, strength and lifetime of a synapse. Spine dynamics are also implicated in long-term memory and cognition: intrinsic fluctuations in volume can explain synapse maintenance over long periods, and rapid, activity-triggered plasticity can relate directly to cognitive processes. Thus, spine dynamics are cellular phenomena with important implications for cognition and memory. Furthermore, impaired spine dynamics can cause psychiatric and neurodevelopmental disorders [e.g. autism, retardation]...
... Discovered in the 19th century and intensely scrutinized in the 20th century, dendritic spines are found in higher animals and some insects. Spines exist only on certain types of neurons, including pyramidal neurons in the cortex, medium spiny neurons in the basal ganglia and Purkinje cells in the cerebellum. Spines are more abundant in higher brain regions and highly variable in shape. Moreover, dendritic spines are the most actin-rich structures in the brain, and their morphology and density are abnormal in several mental disorders...
...Unfortunately, many studies of these correlates reduce every neuron to its action potential. This presents an incomplete picture of cognitive function, and indeed the brain is more than its ions. Recent experiments using optogenetic tools suggest that mechanisms other than spikes can participate in the creation of internal representations. In this section, we attempt to identify connections between the cognitive and synaptic neurosciences to suggest a new synaptic basis for cognitive function. [E.g. attention, computational speed and memory processing. In addition these spines may help solve the binding problem or even possibly the neural correlates of consciousness]...
...The rapid, responsive movement of synapses shares many features with cognition. Dendritic spines can take part directly in cognitive processes to make them more individual, active and stochastic—unlike a computer, in which memory elements obey simple and deterministic rules. Thus, cognitive processes can be easier to understand when we take account of the spine structural dynamics.
Kasai, H., Fukuda, M., Watanabe, S., Hayashi-Takagi, A. & Noguchi, J. (2010) Structural dynamics of dendritic spines in memory and cognition. Trends in Neurosciences. 33(3). 121-129.
SOCRATES: At the Egyptian city of Naucratis, there was a famous old god, whose name was Theuth; the bird which is called the Ibis is sacred to him, and he was the inventor of many arts, such as arithmetic and calculation and geometry and astronomy and draughts and dice, but his great discovery was the use of letters. Now in those days the god Thamus was the king of the whole country of Egypt; and he dwelt in that great city of Upper Egypt which the Hellenes call Egyptian Thebes, and the god himself is called by them Ammon.
To him came Theuth and showed his inventions, desiring that the other Egyptians might be allowed to have the benefit of them; he enumerated them, and Thamus enquired about their several uses, and praised some of them and censured others, as he approved or disapproved of them. It would take a long time to repeat all that Thamus said to Theuth in praise or blame of the various arts. But when they came to letters, This, said Theuth, will make the Egyptians wiser and give them better memories; it is a specific both for the memory and for the wit. Thamus replied: O most ingenious Theuth, the parent or inventor of an art is not always the best judge of the utility or inutility of his own inventions to the users of them. And in this instance, you who are the father of letters, from a paternal love of your own children have been led to attribute to them a quality which they cannot have; for this discovery of yours will create forgetfulness in the learners' souls, because they will not use their memories; they will trust to the external written characters and not remember of themselves. The specific which you have discovered is an aid not to memory, but to reminiscence, and you give your disciples not truth, but only the semblance of truth; they will be hearers of many things and will have learned nothing; they will appear to be omniscient and will generally know nothing; they will be tiresome company, having the show of wisdom without the reality.
"the neural change that accompanies a mental experience at one time (time 1) whose retention, modified or otherwise, allows the individual later (at time 2) to have mental experiences of the kind that would not have been possible in the absence of the trace. (Tulving, 2007, 66)"
"...think of drawing a straight line. After you have drawn it, the line exists physically with all its properties. Then you grasp the pencil again and make the same line a bit longer. After you have done it, the 'second' line exists physically with all its properties. The difference between the two does not exist anywhere other than in your mind." (2007, 67)
I thought I was a good teacher until I discovered my students were just memorizing information rather than learning to understand the material. Who was to blame? The students? The material? I will explain how I came to the agonizing conclusion that the culprit was neither of these. It was my teaching that caused students to fail! I will show how I have adjusted my approach to teaching and how it has improved my students' performance significantly.
1. Ask a question
2. Students think about an answer
3. Students ‘click’ their answer in.
4. Peer discussion
5. Students submit a revised answer.
Whenever he met a new acquaintance, he found out his complete name, the size of his family, the nature of his business and the color of his political opinions. He got all these facts well in mind as part of the picture, and the next time he met that man, even if it was a year later, he was able to slap him on the back, inquire after the wife and kids, and ask him about the hollyhocks in the backyard. No wonder he developed a following! 
Locke... criticized the habit to collect and memorize arguments on the grounds that it misguided the understanding, made an individual "a retainer to others" and did not grant any solid foundation to knowledge. He acknowledged that the accumulation of sentences that was "very familiar among bookish men" could bring them "to furnish themselves with the arguments they meet with pro and con in the questions they study." But he maintained that although such "arguments gathered from other men's thoughts, floating only in the memory," could supply "copious talk with some appearance of reason," they did not help scholars "to judge right nor argue strongly, but only to talk copiously on either side, without being steady and settled in their own judgments." Moreover, "the multiplying variety of arguments" cumbered the memory to no purpose. 
I claim it as established that all books that have been written, or have existed in every region of the earth, all tools, records, inscriptions on wax tablets, epitaphs, all paintings, images, and sculptures; all crosses, of stone, iron, or wood set up at the intersections of two, three, or four roads, and those fixed on monastic houses, placed on top of churches, of houses of charity and bell towers; pillories, forks, gibbets, iron chains, and the swords of justice that are carried before princes for the sake of instilling fear; eye extractions, mutilations, and various tortures of bandits and forgers; all posts that are set up to mark out boundaries; all bell-peals, the clap of wooden tablets in Greek churches, the calls to prayer from the mosques of the Saracens; the blarings of horns and trumpets; all seals; the various dress and tokens of the religious and the dead; alphabets; the insignia of harbors, boats, travelers; inns, taverns, fisheries, nets, messengers, and various entertainers; knights' standards ,the insignia of arms, and armed men; Arabic numerals, astrolabes, clocks, and the seal on a papal bull; the marks and points on knucklebones, varieties of colors, memorial knots, supports for the feet, bandages for the fingers, the lead seals in the staves of penitents; the small notches that seneschals, administrators, and stewards make in sticks when they pay out or receive household expenses; the slaps that bishops give to adults during sacramental annointings; the blows given to boys to preserve the events of history in the memories; the nods and signals of lovers; the whispers of thieves; courteous gifts and small presents--all have been devised for the purpose of supporting the weakness of natural memory.
Boncompagno da Signa, "On Memory" in The Medieval Craft of Memory edited by M. Carruthers and J.M. Ziolkowski. Philadelphia: University of Pennsylvania Press. p.111
Sleep does more than simply consolidate memories in veridical form, additionally transforming and restructuring them so that insights and abstractions can be made, inferences can be drawn, integration can occur, and emotionally salient aspects of information can be preferentially remembered over neutral aspects. (Payne et. al., p.333, in-text references removed)
Animals sustain the ability to operate after injury by creating qualitatively different compensatory behaviors. Although such robustness would be desirable in engineered systems, most machines fail in the face of unexpected damage. We describe a robot that can recover from such change autonomously, through continuous self-modeling. A four-legged machine uses actuation-sensation relationships to indirectly infer its own structure, and it then uses this self-model to generate forward locomotion. When a leg part is removed, it adapts the self-models, leading to the generation of alternative gaits. This concept may help develop more robust machines and shed light on self-modeling in animals. Video of robot, article
Placebo-activated opioids, for example, not only relieve pain; they also modulate heart rate and respiration. The neurotransmitter dopamine, when released by placebo treatment, helps improve motor function in Parkinson's patients. Mechanisms like these can elevate mood, sharpen cognitive ability, alleviate digestive disorders, relieve insomnia, and limit the secretion of stress-related hormones like insulin and cortisol.
In one study, Benedetti found that Alzheimer's patients with impaired cognitive function get less pain relief from analgesic drugs than normal volunteers do. Using advanced methods of EEG analysis, he discovered that the connections between the patients' prefrontal lobes and their opioid systems had been damaged. Healthy volunteers feel the benefit of medication plus a placebo boost. Patients who are unable to formulate ideas about the future because of cortical deficits, however, feel only the effect of the drug itself. The experiment suggests that because Alzheimer's patients don't get the benefits of anticipating the treatment, they require higher doses of painkillers to experience normal levels of relief...
...one way that placebo aids recovery is by hacking the mind's ability to predict the future. We are constantly parsing the reactions of those around us—such as the tone a doctor uses to deliver a diagnosis—to generate more-accurate estimations of our fate. One of the most powerful placebogenic triggers is watching someone else experience the benefits of an alleged drug. Researchers call these social aspects of medicine the therapeutic ritual. [Italics added] Link
...it’s very important to use your brain, to keep challenging your mind, but all mental activities may not be equal. We’re seeing some evidence that a social component may be crucial... The evidence suggests that people who spend long stretches of their days, three hours and more, engrossed in some mental activities like cards may be at reduced risk of developing dementia. Researchers are trying to tease apart cause from effect: Are they active because they are sharp, or sharp because they are active?
.. So far, scientists here have found little evidence that diet or exercise affects the risk of dementia in people over 90. But some researchers argue that mental engagement — doing crossword puzzles, reading books — may delay the arrival of symptoms. And social connections, including interaction with friends, may be very important, some suspect. In isolation, a healthy human mind can go blank and quickly become disoriented...
“There is quite a bit of evidence now suggesting that the more people you have contact with, in your own home or outside, the better you do” mentally and physically, Dr. Kawas said. “Interacting with people regularly, even strangers, uses easily as much brain power as doing puzzles, and it wouldn’t surprise me if this is what it’s all about.” Link
Eliza Dushku plays a young woman called Echo, a member of a group of people known as "Actives" or "Dolls". The Dolls have had their personalities wiped clean so they can be imprinted with any number of new personas, including memory, muscle memory, skills, and language, for different assignments (referred to as engagements). The new persona is... an amalgam of different, existing personalities... The Actives are then hired out for particular jobs – crimes, fantasies, and the occasional good deed... In between tasks, they are mind-wiped into a child-like state... The story follows Echo, who begins, in her mind-wiped state, to become self-aware.The first few episodes created an interesting phenomenon amongst the audience of the show. Online discussion boards were rife with eager fans of Joss Whedon's previous work (e.g. Buffy or Firefly) expressing disappointment about their own emotional detachment from the newest series. The stunts were great, the futuristic science fiction was interesting, but something was missing. What was it?
1. If the machine is in state A, and reads a 0, then it stays in state A, writes a 0, and moves one square to the right.
2. If the machine is in state A, and reads a 1, then it changes to state B, writes a 1, and moves one square to the right.
3. If the machine is in state B, and reads a 0, then it changes to state A, writes a 1 and stops.
4. If the machine is in state B, and reads a 1, then it stays in state B, writes a 1, and moves one square to the right.
I desire to define the different degrees of vividness with which different persons have the faculty of recalling familiar scenes under the form of mental pictures, and the peculiarities of the mental visions of different persons. The first questions that I put referred to the illumination, definition and colouring of the mental image, and they were framed as follows...:-
"Before addressing yourself to any of the Questions on the opposite page, think of some definite object--suppose it is your breakfast-table as you sat down to it this morning--and consider carefully the picture that rises before your mind's eye.
1. Illumination--Is the image dim or fairly clear? Is its brightness comparable to that of the actual scene?
2. Definition--Are all the objects pretty well defined at the same time, or is the place of sharpest definition at any one moment more contracted than it is in a real scene?
3. Colouring--Are the colours of the china, of the toast, bread crust, mustard, meat, parsely, or whatever may have been on the table, quite distinct and natural?" [301-302]
"Many disorders, including Parkinson's, essential tremor, dystonia and obsessive compulsive disorder are characterized by hyperactive brain regions. Deep brain stimulation is replacing lesioning as standard treatment for these disorders, is EMA and FDA approved and is 'very benificial' in 80% of cases (Gritsun et al, 2006)." Link
iPlant, a company selling these device says, "iPlants could help a great number of people suffering from poor monoamine signaling, learning and self-control. Link
The researchers from the University of Munster carried out the human study after results in rats suggested that memory could be boosted by a diet containing 30% fewer calories than normal.Combined with the literature on reduced-calorie diets and lifespan, this new research immediately makes me think of viticulture; i.e., wine-makers know that the best grapes grow in somewhat hostile conditions. What does this say for the human condition? Did God build suffering into the fabric of health?
The study volunteers, who had an average age of 60, were split into three groups - the first had a balanced diet containing the normal number of calories, the second had a similar diet but with a higher proportion of unsaturated fatty acids, such as those found in olive oil and fish. The final group were given the calorie restricted diet.
After three months, there was no difference in memory scores in the first two groups, but the 50 in the third group performed better.
They also showed other signs of physical improvement, with decreased levels of insulin and fewer signs of inflammation...
...care was taken to make sure that the volunteers, despite eating a restricted diet in terms of calories, carried on eating the right amount of vitamins and other nutrients.
...the drop in insulin levels were one plausible reason why mental performance might improve. Link
1. Philosophical poetry is a neglected genre
A neglected beast is either shot or nursed to health.
It depends how much glue we need.
What potential is in this sick creature?
"The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it."
What is the point really? What do I really think?
I'm having a tingling sensation in my concept area-by turns painful and pleasant.
2. Philosophy is a game.
A family resemblance of rules, politics and scoring
Sometimes we run naked across the field with 'fuck you' scrawled on our buttocks.
Bluntness and crudity.
Either way, you'll want to transcend the audience and perform in the spectacle.
Are the successful philosophers the ones on the team?
Or did they just court the right metaphor?
She was the most beautiful metaphor in the kingdom, with her long flowing stream of mental images and divine aesthetic.
Compare the starving artist and the starving philosopher.
Does the latter get published posthumously?
The natural history of philosophical thought is not without interest.( Read more...Collapse )
In the study, Prof. Fried observed the neural activity in the brains of 13 epilepsy patients, as the patients watched clips from TV shows like Seinfeld and The Simpsons. A short while after, the test subjects were asked to describe what they remembered from the video clips. During recall, the exact same neurons that had fired while viewing a clip fired once again while the subject was recalling it. Soon, the researchers were able to predict what clip the subjects would recall just by looking at the neurons that lit up seconds before the recall experience was vocalized. Link
...immediate experience simply will not, of itself, cohere as an autonomous domain. References to physical things are largely what hold [language] together. These references are not just inessential vestiges of the initially inter-subjective character of language, capable of being weeded out by devising an artificially subjective language for sense data. Rather they give us our main continuing access to past sense data themselves; for past sense data are mostly gone for good except as commemorated in physical posits. All we would have apart from posits and speculation are present sense data and present memories of past ones; and a memory trace of a sense datum is too meagre an affair to do much good. Actual memories mostly are traces not of past sensations but of past conceptualization or verbalization. Quine, W.V.O. (1960) Word and Object. MIT Press. p.2-3The point of this passage (for the sake of this post) is that the meaningfulness of our autobiographical memories is abstracted from direct experience or even recollections of sensation. No doubt our strongest memories are adorned with emotion, mental imagery and recreated sensations; but their cognitive impact can be abstracted from these feelings. Remembering is not simply retrieval; it requires the re-creation of past events. We furnish these re-creations with our imagination more than directly retrieving inputs. Thus a variety of non-memory-based mechanisms (e.g. current emotional state) impact how we perceive the past.
FOR ANYONE WHO has ever worried about the power of a vicious rumor, Barack Obama's strategy over the summer [Fight the Smears] must have seemed almost bizarre.
New research into the science of rumors suggests Obama's approach may be a sounder strategy - and the reasons why it makes sense suggest that we misunderstand both how rumors work and why they exist.
By using the tools of evolutionary theory and new approaches to mathematical modeling, researchers are drawing a clearer picture of how and why rumors spread. As they do, they are finding that far from being merely idle or malicious gossip, rumor is deeply entwined with our history as a species. It serves some basic social purposes and provides a valuable window on not just what people talk to each other about, but why.
Our brains aren't terribly adept at distinguishing people who are "actually" important from people who simply receive a lot of attention.
Other than denying a rumor that's true, perhaps the biggest mistake one can make... is to adopt a "no comment" policy: Numerous studies have shown that rumors thrive in environments of uncertainty. Considering that rumors often represent a real attempt to get at the truth, the best way to fight them is to address them in as comprehensive a manner as possible... An effective rebuttal will be more than a denial - it will create a new truth, including an explanation of why the rumor exists and who is benefiting from it.
The more vivid that replacement is, the better [stealing thunder]. When done correctly and early enough in a rumor's lifetime, it can shift the subsequent conversation in beneficial ways. Link [Italics added]
On the one hand, "...olfaction is our slow sense, for it depends on messages carried not at the speed of light or of sound, but at the far statelier pace of a bypassing breeze, a pocket of air enriched with the sort of small, volatile molecules that our nasal-based odor receptors can read.
Yet, on the other hand, olfaction is our quickest sense. Whereas new signals detected from the visual system, auditory system, proprioception (body position), nociception (pain) and gustation (taste) "must first be assimilated by a structural way station called the thalamus before reaching the brain’s interpretive regions, odiferous messages barrel along dedicated pathways straight from the nose and right into the brain’s olfactory cortex, for instant processing. Importantly, the olfactory cortex is embedded within the brain’s limbic system and amygdala, where emotions are born and emotional memories stored. That’s why smells, feelings and memories become so easily and intimately entangled...
...numerous studies have shown that smell memory is long and resilient, and that the earliest odor associations we make often stick...
...while the word and visual cues elicited associations largely from subjects’ adolescence and young adulthood, the smell cues evoked thoughts of early childhood, under the age of 10. And despite the comparative antiquity of such memories, Dr. Larsson said, people described them in exceptionally rich and emotional terms, and they were much likelier to report the sudden sensation of being brought back in time...
...Dr. Larsson attributes the youthfulness of smell memories to the fact that our olfaction is the first of our senses to mature and only later cedes cognitive primacy to vision and words, while the cortical link between olfaction and emotion ensures that those early sensations keep their bloom all life long."
The brain does not simply gather and stockpile information as a computer's hard drive does. Facts are stored first in the hippocampus, a structure deep in the brain about the size and shape of a fat man's curled pinkie finger. But the information does not rest there. Every time we recall it, our brain writes it down again, and during this re-storage, it is also reprocessed. In time, the fact is gradually transferred to the cerebral cortex and is separated from the context in which it was originally learned. For example, you know that the capital of California is Sacramento, but you probably don't remember how you learned it.Epistemology prefers to examine the value of truth, over other values such as moral impact, belief coherence, desire for social approval or emotional saliency. This emphasis goes hand-in-hand with treating memory as a passive mechanism, i.e., 'shit-in/shit-out'. The metaphor of memory as a simple storage and retrieval device does nothing to explain belief revision and why false beliefs may sometimes be justified, rational or valuable to individuals, regardless of their veritistic value.
This phenomenon, known as source amnesia, can also lead people to forget whether a statement is true. Even when a lie is presented with a disclaimer, people often later remember it as true.
With time, this misremembering gets worse. A false statement from a noncredible source that is at first not believed can gain credibility during the months it takes to reprocess memories from short-term hippocampal storage to longer-term cortical storage. As the source is forgotten, the message and its implications gain strength...
...Psychologists have suggested that legends propagate by striking an emotional chord. In the same way, ideas can spread by emotional selection, rather than by their factual merits, encouraging the persistence of falsehoods...
...Journalists and campaign workers may think they are acting to counter misinformation by pointing out that it is not true. But by repeating a false rumor, they may inadvertently make it stronger. In its concerted effort to "stop the smears," the Obama campaign may want to keep this in mind. Rather than emphasize that Obama is not a Muslim, for instance, it may be more effective to stress that he embraced Christianity as a young man.
In 1919, Justice Oliver Wendell Holmes of the Supreme Court wrote that "the best test of truth is the power of the thought to get itself accepted in the competition of the market." Holmes erroneously assumed that ideas are more likely to spread if they are honest. Our brains do not naturally obey this admirable dictum, but by better understanding the mechanisms of memory perhaps we can move closer to Holmes' ideal. Link
Participants briefly viewed pictures of six rooms in a house and subsequently tried to recall the objects in each room... Immediately after viewing the pictures, participants were asked to remember six items from each scene. Participants took turns doing the recall with an anonymous 'other participant' who also recalled six items from the scene. The 'other participant' was actually a computer programmed to provide responses from a list of items in the photos. For three of the scenes, the computer provided the names of two items that had not appeared... Some of these false items would seem very likely to be in the target scene (high-expectancy items); other false items were less likely to be in the target scene (low-expectancy items), though not out of place...The critical recall phase occurred next. Participants were asked to remember as many items from each scene as they could. (Ross, et. al., p.86)Collaboration on this task reduces false memory errors in both older and younger subjects (Ross et.al, 2004).
What Sorts of People Should There Be? is a broad, interdisciplinary, collaborative project in the humanities and social sciences that is focused on human variation, normalcy, and enhancement. By weaving together distinct philosophical, historical, and comparative threads through the establishment of a Canadian-based team of 44 researchers from 18 disciplines, this project will undertake innovative work on this topic at the interface of the humanities, biotechnology, and the social and health sciences.
This is a great question, because grid cells, which are involved in processing spatial information about our surroundings, are located in a brain region that is part of a larger memory system thought to be responsible for the feeling of familiarity. After considering their function in detail, however, I think it seems more likely that a different system of neurons, place cells, plays a stronger role in providing us with the sense that a new locale is familiar—a feeling called “déjà visité.”
In any environment, the brain must keep track of the distinct locations within the surrounding area (say, at the kitchen table versus in front of the refrigerator). It also must note how these different locales relate to one another (the table is three feet to the right of the fridge, for instance). Place cells are involved in the former type of processing; each place cell corresponds to a specific location in an environment and fires when you pass through that spot.
In contrast, grid cells work in a network to produce a kind of internal coordinate system, noting information about distance and direction. These neurons do not correspond to a specific location but become active across several regularly spaced points in any setting. The geometric arrangement of these cells, relative to one another and to the external setting, ultimately helps us form a mental map of a certain environment.
Grid cells are located in the entorhinal cortex, a brain region that processes information before sending it to the hippocampus, the area where place cells are located. Because we know that place cells have a unique firing pattern for nearly every experience, it is likely that the hippocampus, and not primarily the entorhinal cortex, decides whether a location is novel or being revisited. When a strange place is experienced as familiar, it may be because the activated ensemble of place cells at that location happens to be similar to a pattern of activity that was elicited by a previous locale. Link
Know how a whiff of certain odors can take you back in time, either to a great memory or bad one? It turns out emotion plays an even bigger role with the nose, and that your sense of smell actually can sharpen when something bad happens.
Northwestern University researchers proved the surprising connection by giving volunteers electric shocks while they sniffed novel odors.
The discovery, reported in Friday's edition of the journal Science, helps explain how our senses can steer us clear of danger. More intriguing, it could shed light on disorders such as post-traumatic stress syndrome.
"This is an incredibly unique study," said Dr. David Zald, a Vanderbilt University neuroscientist who studies how the brain handles sensory and emotional learning. "We're talking about a change in our perceptual abilities based on emotional learning."
Scientists long have known of a strong link between the sense of smell and emotion. A certain perfume or scent of baking pie, for instance, can raise memories of a long-dead loved one. Conversely, a whiff of diesel fuel might trigger a flashback for a soldier suffering PTSD.
Could an emotionally charged situation make that initial cue be perceived more strongly in the first place?
The research team recruited 12 healthy young adults to find out.
Volunteers repeatedly smelled sets of laboratory chemicals with odors distinctly different from ones in everyday life. An "oily grassy" smell is the best description that lead researcher Wen Li, a Northwestern postdoctoral fellow in neuroscience, could give.
Two of the bottles in a set contained the same substance and the third had a mirror image of it, meaning its odor normally would be indistinguishable. By chance, the volunteers correctly guessed the odd odor about one-third of the time.
Then Li gave the volunteers mild electric shocks while they smelled just the odd chemical. In later smell tests, they could correctly pick out the odd odor 70 percent of the time.
MRI scans showed the improvement was more than coincidence. There were changes in how the brain's main olfactory region stored the odor information, essentially better imprinting the shock-linked scent so it could be distinguished more quickly from a similar odor.
In other words, the brain seems to have a mechanism to sniff out threats.
That almost is certainly a survival trait evolved to help humans rapidly and subconsciously pick a dangerous odor from the sea of scents constantly surrounding us, Li said. Today, that might mean someone who has been through a kitchen fire can tell immediately if a whiff of smoke has that greasy undertone or simply comes from the fireplace.
But the MRI scans found the brain's emotional regions did not better discriminate among the different odors, Li noted. That discrepancy between brain regions is where anxiety disorders may come in. If someone's olfactory region does not distinguish a dangerous odor signal from a similar one, the brain's emotional fight-or-flight region can overreact.
Researchers say that is a theory not yet tested.
For now, Northwestern neuroscientist Jay Gottfried, the study's senior author, says the work illuminates a sense that society too often gives short shrift.
"People really dismiss the sense of smell," said Gottfried, who researches "how the brain can put together perceptions of hundreds of thousands of different smells. ... Work like this really says that the human sense of smell has much more capacity than people usually give it credit."
While many saw Lewis as kin to the logical empiricists, he was never truly comfortable in such company because he declined to divorce experience from cognition. Positivism rejected value as lacking cognitive significance, also rejecting the analysis of experience in favor of physicalism. Both rejections struck him as regrettable. Indeed his growing awareness of the pragmatic tradition led him in the opposite direction. For Lewis, it is only within experience that anything can have significance for anything, and thus he came to see value as a way of representing the significance of knowledge for future conduct. These convictions led him to reflect on the differences between pragmatism and positivism, and on the cognitive structure of value experiences.
The external impression was somewhat striking; and it remains vivid with me. I can still see him as he came through that gate out there on Quincy Street; a taller than average figure, erect and well set up, walking with easy gait like that of a man who has sometime learned to march. He appeared observant of whatever went on about him, but not engaged with it-a little aloof perhaps, as if his thoughts were elsewhere. He wore a longish military cape, instead of an overcoat, coming over from his rooms, and I can see him as he swung it off at the door. The complexion was a little darker than the average, indicative of the Spanish strain in his inheritance; and the eyes at once drew notice. The features and general presence were such as I can only suggest by the word "aristocratic."(p.29)
“The day of [my sister's] birth is my earliest memory, or my earliest datable memory, anyway. I distinctly remember playing with a bit of plasticine in the kitchen while my father rushed in and out of the room, hurrying backwards and forwards to my mother, who was giving birth in their bedroom. I know I didn't invent this memory because I checked the details later with my mother. I also have a vivid mental picture of walking into their bedroom a little while later, hand in hand with my father, and seeing my mother lying in bed in her nightdress next to my beaming sister, who is stark naked with a full head of hair and looks about five years old. Although I clearly pasted together this bizarre false memory out of bits of hearsay when I was a child, it is so vivid that it still comes to mind if I ever think about Di being born.”
"A person has an apparent recollection of something from early childhood, and wonders whether he really remembers it. His parents may tell him that what he describes did happen, and that he witnessed it, but the discussion of whether he remembers it still goes on. They wonder whether his witnessing of the event has any connection with his now giving the story or whether his description can be completely explained by what he heard later." (p.176) [my italics]
...During sleep, the reactivated memories of real-time experiences are processed within the brain at a higher rate of speed. That rate can be as much as six or seven times faster, and is described as “thought speed.”What is most interesting about this research from my perspective is the relevance for source-monitoring. Source-monitoring refers to how we determine whether our memories are of a real event, a dream or just a fiction. One of the ways we evaluate memories is to bring to bear information from different modalities. E.g. If we cannot draw a memory that is tactile for an intimate experience, then it is evidence that we only dreamt of the encounter. It is incredible to see experimental evidence of memories forming that parallels theoretical work done in cognitive psychology on mental experiences.
Memory stores patterns of activity in modular form in the brain’s cortex. Different modules in the cortex process different kinds of information - sounds, sights, tastes, smells, etc. The cortex sends these networks of activity to a region called the hippocampus. The hippocampus then creates and assigns a tag, a kind of temporary bar code, that is unique to every memory and sends that signal back to the cortex.
Each module in the cortex uses the tag to retrieve its own part of the activity. A memory of having lunch, for example, would involve a number of modules, each of which might record where the diner sat, what was served, the noise level in the restaurant or the financial transaction to pay for the meal.
But while an actual dining experience might have taken up an hour of actual time, replaying the memory of it would only take 8 to 10 minutes. The reason... is that the speed of the consolidation process isn’t constrained by the real world physical laws that regulate activity in time and space.
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