<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Bartonellosis and can you explain it in depth? [/INST] Bartonellosis is an infectious disease produced by bacteria of the genus Bartonella.Bartonella species cause diseases such as Carrións disease, trench fever, cat-scratch disease, bacillary angiomatosis, peliosis hepatis, chronic bacteremia, endocarditis, chronic lymphadenopathy, and neurological disorders.

Presentation
Carrións disease
Patients can develop two clinical phases: an acute septic phase and a chronic eruptive phase associated with skin lesions. In the acute phase (also known as Oroya fever or fiebre de la Oroya), B. bacilliformis infection is a sudden, potentially life-threatening infection associated with high fever and decreased levels of circulating red blood cells (i.e., hemolytic anemia) and transient immunosuppression. B. bacilliformis is considered the most deadly species to date, with a death rate of up to 90% during the acute phase, which typically lasts two to four weeks. Peripheral blood smears show anisomacrocytosis with many bacilli adherent to red blood cells. Thrombocytopenia is also seen and can be very severe. Neurologic manifestations (neurobartonellosis) are altered mental status, agitation, or even coma, ataxia, spinal meningitis, or paralysis. It is seen in 20% of patients with acute infection, in which the prognosis is very guarded with an about 50% mortality. The most feared complication is overwhelming infection mainly by Enterobacteriaceae, particularly Salmonella (both S. typhi and  S. non-typhi, as well as reactivation of toxoplasmosis and other opportunistic infections .The chronic manifestation consists of a benign skin eruption with raised, reddish-purple nodules (angiomatous tumours). The bacterium can be seen microscopically, if a skin biopsy is silver stained (the Warthin–Starry method).

Cat-scratch disease
Cat-scratch disease is due to an infection by B. henselae and manifests as gradual regional lymph nodes enlargement (axilla, groin, neck) which may last 2–3 months or longer and a distal scratch and/or red-brown skin papule (not always seen at the time of the disease). The enlarged lymph node is painful and tender. The lymph nodes may suppurate, some patients may remain afebrile or asymptomatic. Other presentations include fever (particularly in children), Parinauds oculoglandular syndrome, encephalopathy, and neuroretinitis.B. henselae can be associated with bacteremia, bacillary angiomatosis, and peliosis hepatis in HIV patients, and bacteremia and endocarditis in immunocompetent and immunocompromised patients. Symptoms may include fatigue, headaches, fever, memory loss, disorientation, insomnia, and loss of coordination. The bacteria block the normal immune response by suppressing the NF-κB apoptosis pathway. Disease progression may be accelerated if the host is subsequently infected by an immune-suppressing virus such as Epstein Barr virus.

Bacillary angiomatosis
B. henselae and B. quintana can cause bacillary angiomatosis, a vascular proliferative disease involving mainly the skin, and other organs. The disease was first described in human immunodeficiency virus (HIV) patients and organ transplant recipients. Severe, progressive and disseminated disease may occur in HIV  patients. Differential diagnoses include Kaposis sarcoma, pyogenic granuloma, hemangioma, verruga peruana, and subcutaneous tumors. Lesions can affect bone marrow, liver, spleen, or lymph nodes.

Peliosis hepatis
B. henselae is the etiologic agent for peliosis hepatis, which is defined as a vascular proliferation of sinusoid hepatic capillaries resulting in blood-filled spaces in the liver in HIV patients and organ transplant recipients. Peliosis hepatis can be associated with peliosis of the spleen, as well as bacillary angiomatosis of the skin in HIV patients.

Trench fever
Trench fever, also known as five-day fever or quintan fever, is the initial manifestation of B. quintana infection. Clinical manifestations range from asymptomatic infection to severe illness. Classical presentations include a febrile illness of acute onset, headache, dizziness, and shin pain. Chronic infection manifestations include attacks of fever and aching in some cases and persistent bacteremia in soldiers and homeless people.

Microbiology
Members of the genus Bartonella are facultative intracellular bacteria, alpha 2 subgroup Pseudomonadota. The genus comprises:

Pathophysiology
In mammals, each Bartonella species is highly adapted to its reservoir host as the result of intracellular parasitism and can persist in the bloodstream of the host. Intraerythrocytic parasitism is only observed in the acute phase of Carrions disease. Bartonella species also have a tropism for endothelial cells, observed in the chronic phase of Carrions disease (also known as verruga Peruana) and bacillary angiomatosis.
Pathological response can vary with the immune status of the host. Infection with B. henselae can result in a focal suppurative reaction (CSD in immunocompetent patients), a multifocal angioproliferative response (bacillary angiomatosis in immunocompromised patients), endocarditis, or meningitis.

Diagnosis
There are several methods used for diagnosing Bartonella infection including microscopy, serology, and PCR. Microscopy of blood smears is used to diagnose Carrións disease (B. bacilliformis), however for other Bartonella species, microscopy and silver staining are insensitive, not highly specific, and cannot differentiate species. The CDC does not recommend lymph node aspiration for diagnostic purposes.

Serology and protein-based methods
IFA (immunofluorescence antibody assay) testing for the presence of antibodies in serum is used to diagnose B. henselae infection at the acute onset of Cat Scratch Disease symptoms, followed by PCR to confirm infecting species. IFA can generally be used to confirm a diagnosis of Bartonella infection, but is limited by antibody cross-reactivity with other bacteria species  which can cause a false positive, and antigen variability which can result in false negatives.Bartonella spp. often evade an immune response, thus antibodies may not be detected even concurrent with an infection, resulting in an IFA false negative rate of up to 83% in chronically infected patients when other test results (e.g. organism isolation or PCR) are positive. IFA sensitivity may range from 14 to 100%, causing discrepancies between PCR and serology test results. Positive IFA results do not distinguish between current infection and prior exposure.ELISA (enzyme-linked immunosorbent assay) is another method that has been used to detect Bartonella, but it has a low sensitivity (17-35%). Western blot for protein detection of Bartonella-associated proteins has also been reported, but this method does not show clear immunoreactive profiles.

PCR
The CDC states that PCR testing from a single blood draw is not sufficiently sensitive for B. henselae testing, and can result in high false negative rates  due to a small sample volume and levels below the limit of molecular detection.Bartonella spp. are fastidious, slow-growing bacteria that are difficult to grow using traditional solid agar plate culture methods due to complex nutritional requirements and potentially a low number of circulating bacteria. This conventional method of culturing Bartonella spp. from blood inoculates plated directly onto solid agar plates requires an extended incubation period of 21 days due to the slow growth rate.

Enrichment Culture
Bartonella growth rates improve when cultured in an enrichment inoculation step in a liquid insect-based medium  such as Bartonella Alphaproteobacteria Growth Medium (BAPGM)  or Schneiders Drosophila-based insect powder medium. Several studies have optimized the growing conditions of Bartonella spp. cultures in these liquid media, with no change in bacterial protein expressions or host interactions in vitro. Insect-based liquid media supports the growth and co-culturing of at least seven Bartonella species, reduces bacterial culturing time and facilitates PCR detection and isolation of Bartonella spp. from animal and patient samples. Research shows that DNA may be detected following direct extraction from blood samples and become negative following enrichment culture, thus PCR is recommended after direct sample extraction and also following incubation in enrichment culture. Several studies have successfully optimized sensitivity and specificity by using PCR amplification (pre-enrichment PCR) and enrichment culturing of blood draw samples, followed by PCR (post-enrichment PCR) and DNA sequence identification.

Serial Testing
As Bartonella spp. infect at low levels and cycle between blood and tissues, multiple blood draws over time may be necessary to detect infection.

Treatment
Treatment of infections caused by Bartonella species include:
Some authorities recommend the use of azithromycin.

Epidemiology
Carrións disease, or Oroya fever, or Peruvian wart is a rare infectious disease found only in Peru, Ecuador, and Colombia. It is endemic in some areas of Peru, is caused by infection with the bacterium Bartonella bacilliformis, and transmitted by sandflies of genus Lutzomyia.
Cat scratch disease occurs worldwide. Cats are the main reservoir of Bartonella henselae, and the bacterium is transmitted to cats by the cat flea Ctenocephalides felis. Infection in cats is very common with a prevalence estimated between 40 and 60%, younger cats being more commonly infective. Cats usually become immune to the infection, while dogs may be very symptomatic. Humans may also acquire it through flea or tick bites from infected dogs, cats, coyotes, and foxes.Trench fever, produced by Bartonella quintana infection,  is transmitted by the human body louse Pediculus humanus corporis.  Humans are the only known reservoir. Thorough washing of clothing may help to interrupt the transmission of infection.A possible role for ticks in transmission of Bartonella species remains to be elucidated; in November 2011, Bartonella rochalimae, B. quintana, and B. elizabethae DNA was first reported in Rhipicephalus sanguineus and Dermacentor nitens ticks in Peru.

History
Carrións disease
The disease was named after medical student Daniel Alcides Carrión from Cerro de Pasco, Peru. Carrión described the disease after being inoculated at his request with the pus of a skin lesion from patient Carmen Paredes in 1885 by Doctor Evaristo M. Chávez, a close friend and coworker in Dos de Mayo National Hospital. Carrión developed the disease three weeks after the inoculation and kept a meticulous record of clinical symptoms and signs until the disease rendered him incapable of the task and he died at age 28 several weeks later—October 5, 1885. Carrión proved that Oroya fever and verruga peruana were two stages of the same disease, and not two different diseases as was thought at the time. His work did not result in a cure immediately, but his research started the process </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Trypanosomiasis and can you explain it in depth? [/INST] Trypanosomiasis or trypanosomosis is the name of several diseases in vertebrates caused by parasitic protozoan trypanosomes of the genus Trypanosoma. In humans this includes African trypanosomiasis and Chagas disease. A number of other diseases occur in other animals.
African trypanosomiasis, which is caused by either Trypanosoma brucei gambiense or Trypanosoma brucei rhodesiense, threatens some 65 million people in sub-Saharan Africa, especially in rural areas and populations disrupted by war or poverty. The number of cases  has been going down due to systematic eradication efforts: in 1998 almost 40,000 cases were reported but almost 300,000 cases were suspected to have occurred; in 2009, the number dropped below 10,000; and in 2018 it dropped below 1000. Chagas disease causes 21,000 deaths per year mainly in Latin America.

Signs and symptoms
The tsetse fly bite erupts into a red chancre sore and within a few weeks, the person can experience fever, swollen lymph glands, blood in urine, aching muscles and joints, headaches and irritability. In the first phase, the patient has only intermittent bouts of fever with lymphadenopathy together with other non-specific signs and symptoms. The second stage of the disease is marked by involvement of the central nervous system with extensive neurological effects like changes in personality, alteration of the biological clock (the circadian rhythm), confusion, slurred speech, seizures and difficulty in walking and talking. These problems can develop over many years and if not treated, the person dies. It is common in Subsaharan Africa.

Diagnosis
Cattle may show enlarged lymph nodes and internal organs. Haemolytic anaemia is a characteristic sign. Systemic disease and reproductive wastage are common, and cattle appear to waste away.
Horses with dourine show signs of ventral and genital edema and urticaria.
Infected dogs and cats may show severe systemic signs.
Diagnosis relies on recognition of the flagellate on a blood smear. Motile organisms may be visible in the buffy coat when a blood sample is spun down. Serological testing is also common.

Prevention
The use of trypanotolerant breeds for livestock farming should be considered if the disease is widespread. Fly control is another option but is difficult to implement. The main approaches to controlling African trypanosomiasis are to reduce the reservoirs of infection and the presence of the tsetse fly. Screening of people at risk helps identify patients at an early stage. Diagnosis should be made as early as possible and before the advanced stage to avoid complicated, difficult and risky treatment procedures.

Treatment
Stage I of the condition is usually treated with pentamidine or suramin through intramuscular injection or intravenous infusion if sufficient observation is possible. Stage II of the disease is typically treated with melarsoprol or eflornithine preferably introduced to the body intravenously. Both pentamidine and suramin have limited side effects. Melarsoprol is extremely effective but has many serious side effects which can cause neurological damage to a patient, however, the drug is often a patients last hope in many late stage cases. Eflornithine is extremely expensive but has side effects that may be treated with ease. In regions of the world where the disease is common eflornithine is provided for free by the World Health Organization.

Research
Trypanosomiasis could, in future be prevented by genetically altering the tsetse fly. As the tsetse fly is the main vector of transmission, making the fly immune to the disease by altering its genome could be the main component in an effort to eradicate the disease. New technologies such as CRISPR allowing cheaper and easier genetic engineering could allow for such measures. A pilot program in Senegal, funded by the International Atomic Energy Agency, has considerably reduced the tsetse fly population by introducing male flies which have been sterilized by exposure to gamma rays. This has allowed a change of cattle breeds from lower producing trypanotolerant breeds to higher-producing foreign breeds, and was selected as one of the Best Sustainable Development Practices on Food Security by EXPO Milan 2015.

Other animals
Nagana, or animal African trypanosomiasis, also called Souma or Soumaya in Sudan.
Surra
Mal de cadeiras, or Quebra Bunda (of central South America, Brazil)
Murrina de caderas (of Panama;  Derrengadera de caderas)
Dourine
Cachexial fevers (various)
Gambian horse sickness (of central Africa)
Baleri  (of Sudan)
Kaodzera  (Rhodesian trypanosomiasis)
Tahaga  (a disease of camels in Algeria)
Galziekte, galzietzke (bilious fever of cattle; gall sickness of South Africa)
Peste-boba (of Venezuela; Derrengadera)Some species of cattle such as the African buffalo, Ndama, and Keteku appear trypanotolerant and do not develop symptoms. Calves are more resistant than adults.Tsetse-borne species of trypanosomes have entered zoos outside the traditional tsetse zone in infected animals imported for the zoo.

References
Bibliography
Thomas, H Wolferstan (1905). Report on trypanosomes, trypanosomiasis, and sleeping sickness : being an experimental investigation into their pathology and treatment. London: University Press of Liverpool. OCLC 11692559.
Manson, Patrick (1914) </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Malunion and can you explain it in depth? [/INST] A malunion is when a fractured bone does not heal properly.  Some ways that it shows is by having the bone being twisted, shorter, or bent. Malunions can occur by having the bones improperly aligned when immobilized, having the cast taken off too early, or never seeking medical treatment after the break. Malunions are painful and commonly produce swelling around the area, possible immobilization, and deterioration of the bone and tissue.

Signs and symptoms
Malunions are presented by excessive swelling, twisting, bending, and possibly shortening of the bone </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Impulsivity and can you explain it in depth? [/INST] In psychology, impulsivity (or impulsiveness) is a tendency to act on a whim, displaying behavior characterized by little or no forethought, reflection, or consideration of the consequences. Impulsive actions are typically "poorly conceived, prematurely expressed, unduly risky, or inappropriate to the situation that often result in undesirable consequences," which imperil long-term goals and strategies for success. Impulsivity can be classified as a multifactorial construct. A functional variety of impulsivity has also been suggested, which involves action without much forethought in appropriate situations that can and does result in desirable consequences. "When such actions have positive outcomes, they tend not to be seen as signs of impulsivity, but as indicators of boldness, quickness, spontaneity, courageousness, or unconventionality" Thus, the construct of impulsivity includes at least two independent components: first, acting without an appropriate amount of deliberation, which may or may not be functional; and second, choosing short-term gains over long-term ones.Impulsivity is both a facet of personality and a major component of various disorders, including FASD, ADHD, substance use disorders, bipolar disorder, antisocial personality disorder, and borderline personality disorder. Abnormal patterns of impulsivity have also been noted instances of acquired brain injury and neurodegenerative diseases. Neurobiological findings suggest that there are specific brain regions involved in impulsive behavior, although different brain networks may contribute to different manifestations of impulsivity, and that genetics may play a role.Many actions contain both impulsive and compulsive features, but impulsivity and compulsivity are functionally distinct. Impulsivity and compulsivity are interrelated in that each exhibits a tendency to act prematurely or without considered thought and often include negative outcomes.  Compulsivity may be on a continuum with compulsivity on one end and impulsivity on the other, but research has been contradictory on this point. Compulsivity occurs in response to a perceived risk or threat, impulsivity occurs in response to a perceived immediate gain or benefit, and, whereas compulsivity involves repetitive actions, impulsivity involves unplanned reactions.
Impulsivity is a common feature of the conditions of gambling and alcohol addiction. Research has shown that individuals with either of these addictions discount delayed money at higher rates than those without, and that the presence of gambling and alcohol abuse lead to additive effects on discounting.

Impulse
An impulse is a wish or urge, particularly a sudden one. It can be considered as a normal and fundamental part of human thought processes, but also one that can become problematic, as in a condition like obsessive-compulsive disorder, borderline personality disorder, attention deficit hyperactivity disorder, or in fetal alcohol spectrum disorders.
The ability to control impulses, or more specifically control the desire to act on them, is an important factor in personality and socialization. Deferred gratification, also known as impulse control is an example of this, concerning impulses primarily relating to things that a person wants or desires. Delayed gratification comes when one avoids acting on initial impulses. Delayed gratification has been studied in relation to childhood obesity. Resisting the urge to act on impulses is important to teach children, because it teaches the value of delayed gratification.
Many psychological problems are characterized by a loss of control or a lack of control in specific situations. Usually, this lack of control is part of a pattern of behavior that also involves other maladaptive thoughts and actions, such as substance abuse problems or sexual disorders like the paraphilias (e.g. pedophilia and exhibitionism). When loss of control is only a component of a disorder, it usually does not have to be a part of the behavior pattern, and other symptoms must also be present for the diagnosis to be made. (Franklin)

The five traits that can lead to impulsive actions
For many years it was understood that impulsivity is a trait but with further analysis it can be found that there were five traits that can lead to impulsive actions:
positive urgency,
negative urgency,
sensation seeking,
lack of planning, and
lack of perseverance.

Associated behavioral and societal problems
Attention-deficit hyperactivity disorder
Attention deficit-hyperactivity disorder (ADHD) is a multiple component disorder involving inattention, impulsivity, and hyperactivity.  The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) breaks ADHD into three subtypes according to the behavioral symptoms:
Attention-Deficit/Hyperactivity Disorder Predominantly Inattentive Type,
Attention-Deficit/Hyperactivity Disorder Predominantly Hyperactive-Impulsive Type, and
Attention-Deficit/Hyperactivity Disorder Combined Type.
Predominantly hyperactive-impulsive type symptoms may include
fidgeting and squirming in seats,
talking nonstop,
dashing around and touching or playing with anything in sight,
having trouble sitting still during dinner/school/story time,
being constantly in motion, and
having difficulty doing quiet tasks or activities.
Other manifestations primarily of impulsivity include
being very impatient,
having difficulty waiting for things they want or waiting their turns in games,
often interrupting conversations or others activities, or
blurting out inappropriate comments, showing their emotions without restraint, and act without regard for consequences.
Prevalence of the disorder worldwide is estimated to be between 4% and 10%, with reports as low as 2.2% and as high as 17.8%. Variation in rate of diagnoses may be attributed to differences between populations (i.e. culture), and differences in diagnostic methodologies. Prevalence of ADHD among females is less than half that of males, and females more commonly fall into the inattentive subtype.Despite an upward trend in diagnoses of the inattentive subtype of ADHD, impulsivity is commonly considered to be the central feature of ADHD, and the impulsive and combined subtypes are the major contributors to the societal costs associated with ADHD. The estimated cost of illness for a child with ADHD is $14,576 (in 2005 dollars) annually. Prevalence of ADHD among prison populations is significantly higher than that of the normal population.In both adults and children, ADHD has a high rate of comorbidity with other mental health disorders such as learning disability, conduct disorder, anxiety disorder, major depressive disorder, bipolar disorder, and substance use disorders.
The precise genetic and environmental factors contributing to ADHD are relatively unknown, but endophenotypes offer a potential middle ground between genes and symptoms. ADHD is commonly linked to "core" deficits involving "executive function," "delay aversion," or "activation/arousal" theories that attempt to explain ADHD through its symptomology. Endophenotypes, on the other hand, purport to identify potential behavioral markers that correlate with specific genetic etiology. There is some evidence to support deficits in response inhibition as one such marker.  Problems inhibiting prepotent responses are linked with deficits in pre-frontal cortex (PFC) functioning, which is a common dysfunction associated with ADHD and other impulse-control disorders.Evidence-based psychopharmacological and behavioral interventions exist for ADHD.

Substance abuse
Impulsivity appears to be linked to all stages of  substance abuse.The acquisition phase of substance abuse involves the escalation from single use to regular use.  Impulsivity may be related to the acquisition of substance abuse because  of the potential role that instant gratification provided by the substance may offset the larger future benefits of abstaining from the substance, and because people with impaired inhibitory control may not be able to overcome motivating environmental cues, such as peer pressure.  "Similarly, individuals that discount the value of delayed reinforcers begin to abuse alcohol, marijuana, and cigarettes early in life, while also abusing a wider array of illicit drugs compared to those who discounted delayed reinforcers less."Escalation or dysregulation is the next and more severe phase of substance abuse.  In this phase individuals "lose control" of their addiction with large levels of drug consumption and binge drug use.  Animal studies  suggest that individuals with higher levels of impulsivity may be more prone to the escalation stage of substance abuse.Impulsivity is also related to the abstinence, relapse, and treatment stages of substance abuse.  People who scored high on the Barratt Impulsivity Scale (BIS) were more likely to stop treatment for cocaine abuse.  Additionally, they adhered to treatment for a shorter duration than people that scored low on impulsivity.  Also, impulsive people had greater cravings for drugs during withdrawal periods and were more likely to relapse.  This effect was shown in a study where smokers that test high on the BIS had increased craving in response to smoking cues, and gave into the cravings more quickly than less impulsive smokers.  Taken as a whole the current research suggests that impulsive individuals are less likely to abstain from drugs and more likely to relapse earlier than less impulsive individuals.While it is important to note the effect of impulsivity on substance abuse, the reciprocating effect whereby substance abuse can increase impulsivity has also been researched and documented.   The promoting effect of impulsivity on substance abuse and the effect of substance abuse on increased impulsivity creates a positive feedback loop that maintains substance seeking behaviors.  It also makes conclusions about the direction of causality difficult.  This phenomenon has been shown to be related to several substances, but not all.  For example, alcohol has been shown to increase impulsivity while amphetamines have had mixed results.Substance use disorder treatments include prescription of medications such as acamprosate, buprenorphine, disulfiram, LAAM, methadone, and naltrexone, as well as effective psychotherapeutic treatment like
behavioral couples therapy, CBT, contingency management, motivational enhancement therapy, and relapse prevention.

Eating
Impulsive overeating spans from an episode of indulgence by an otherwise healthy person to chronic binges by a person with an eating disorder.Consumption of a tempting food by non-clinical individuals increases when self-regulatory resources are previously depleted by another task, suggesting that it is caused by a breakdown in self control.  Impulsive eating of unhealthy snack foods appears to be regulated by individual differences in impulsivity when self-control is weak and by attitudes towards the snack and towards healthy eating when self-control is strong. There is also evidence that greater food consumption occurs when people are in a sad mood, although it is possible that this is due more to emotional regulation than to a lack of self-control. In these cases, overeating will only take place if the food is palatable to the person, and if so individual differences in impulsivity can predict the amount of consumption.Chronic overeating is a behavioral component of binge eating disorder, compulsive overeating, and bulimia nervosa. These diseases are more common for women and may involve eating thousands of calories at a time.  Depending on which of these disorders is the underlying cause, an episode of overeating can have a variety of different motivations. Characteristics common among these three disorders include low self-esteem, depression, eating when not physically hungry, preoccupation with food, eating alone due to embarrassment, and feelings of regret or disgust after an episode.  In these cases, overeating is not limited to palatable foods.Impulsivity differentially affects disorders involving the overcontrol of food intake (such as anorexia nervosa) and disorders involving the lack of control of food intake (such as bulimia nervosa). Cognitive impulsivity, such as risk-taking, is a component of many eating disorders, including those that are restrictive.  However, only people with disorders involving episodes of overeating have elevated levels of motoric impulsivity, such as reduced response inhibition capacity.One theory suggests that binging provides a short-term escape from feelings of sadness, anger, or boredom, although it may contribute to these negative emotions in the long-term.  Another theory suggests that binge eating involves reward seeking, as evidenced by decreased serotonin binding receptors of binge-eating women compared to matched-weight controls and predictive value of heightened reward sensitivity/drive in dysfunctional eating.Treatments for clinical-grade overeating include cognitive behavioral therapy to teach people how to track and change their eating habits and actions, interpersonal psychotherapy to help people analyze the contribution of their friends and family in their disorder, and pharmacological therapies including antidepressants and SSRIs.

Impulse buying
Impulse buying consists of purchasing a product or service without any previous intent to make that purchase. It has been speculated to account for as much as eighty percent of all purchases in the United States.There are several theories pertaining to impulsive buying.  One theory suggests that it is exposure combining with the speed that a reward can be obtained that influences an individual to choose lesser immediate rewards over greater rewards that can be obtained later. For example, a person might choose to buy a candy bar because they are in the candy aisle even though they had decided earlier that they would not buy candy while in the store.
Another theory is one of self-regulation which suggests that the capacity to refrain from impulsive buying is a finite resource.  As this capacity is depleted with repeated acts of restraint susceptibility to purchasing other items on impulse increases.Finally, a third theory suggests an emotional and behavioral tie between the purchaser and the product which drives both the likelihood of an impulsive purchase as well as the degree that a person will retroactively be satisfied with that purchase result.  Some studies have shown a large number of individuals are happy with purchases made on impulse (41% in one study) which is explained as a preexisting emotional attachment which has a positive relationship both with the likelihood of initiating the purchase as well as mitigating post purchase satisfaction.  As an example, when purchasing team-related college paraphernalia a large percentage of those purchases are made on impulse and are tied to the degree with which a person has positive ties to that team.Impulsive buying is seen both as an individual trait in which each person has a preconditioned or hereditary allotment, as well as a situational construct which is mitigated by such things as emotion in the moment of the purchase and the preconditioned ties an individual has with the product.Psychotherapy and pharmacological treatments have been shown to be helpful interventions for patients with impulsive-compulsive buying disorder.
Psychotherapy interventions include the use of desensitization techniques, self-help books or attending a support group.
Pharmacological interventions include the use of SSRIs, such as fluvoxamine, citalopram, escitalopram, and naltrexone.

Impulse control disorders not elsewhere classified
Impulse control disorder (ICDs) are a class of DSM diagnoses that do not fall into the other diagnostic categories of the manual (e.g. substance use disorders), and that are characterized by extreme difficulty controlling impulses or urges despite negative consequences.  Individuals suffering from an impulse control disorder frequently experience five stages of symptoms: compelling urge or desire, failure to resist the urge, a heightened sense of arousal, succumbing to the urge (which usually yields relief from tension), and potential remorse or feelings of guilt after the behavior is completed. Specific disorders included within this category include intermittent explosive disorder, kleptomania, pathological gambling, pyromania, trichotillomania (hair-pulling disorder), and impulse control disorders not otherwise specified (ICD NOS). ICD NOS includes other significant difficulties that seem to be related to impulsivity but do not meet the criteria for a specific DSM diagnosis.There has been much debate over whether or not the ICDs deserve a diagnostic category of their own, or whether they are in fact phenomenologically and epidemiologically related to other major psychiatric conditions like obsessive-compulsive disorder (OCD), affective disorders, and addictive disorders. In fact, the ICD classification is likely to change with the release of the DSM-V in May 2013.  In this new revision the ICD NOS will likely be reduced or removed; proposed revisions include reclassifying trichotillomania (to be renamed hair-pulling disorder) and skin-picking disorder as obsessive-compulsive and related disorders, moving intermittent explosive disorder under the diagnostic heading of disruptive, impulse control, and conduct disorders, and gambling disorder may be included in addiction and related disorders.The role of impulsivity in the ICDs varies.  Research on kleptomania and pyromania is lacking, though there is some evidence that greater kleptomania severity is tied to poor executive functioning.Trichotillomania and skin-picking disorder seem to be disorders that primarily involve motor impulsivity, and will likely be classified in the DSM-V within the obsessive-compulsive and related disorders category.Pathological gambling, in contrast, seems to involve many diverse aspects of impulsivity and abnormal reward circuitry  (similar to substance use disorders) that has led to it being increasingly conceptualized as a non-substance or behavioral addiction. Evidence elucidating the role of impulsivity in pathological gambling is accumulating, with pathological gambling samples demonstrating greater response impulsivity, choice impulsivity, and reflection impulsivity than comparison control samples. Additionally, pathological gamblers tend to demonstrate greater response perseveration (compulsivity) and risky decisionmaking in laboratory gambling tasks compared to controls, though there is no strong evidence suggesting that attention and working memory are impaired in pathological gamblers. These relations between impulsivity and pathological gambling are confirmed by brain function research: pathological gamblers demonstrate less activation in the frontal cortical regions (implicated in impulsivity) compared to controls during behavioral tasks tapping response impulsivity, compulsivity, and risk/reward.  Preliminary, though variable, findings also suggest that striatal activation is different between gamblers and controls, and that neurotransmitter differences (e.g. dopamine, serotonin, opioids, glutamate, norepinephrine) may exist as well.Individuals with intermittent explosive disorder, also known as impulsive aggression, have exhibited serotonergic abnormalities and show differential activation in response to emotional stimuli and situations.  Notably, intermittent explosive disorder is not associated with a higher likelihood of diagnosis with any of the other ICDs but is highly comorbid with disruptive behavior disorders in childhood.  Intermittent explosive disorder is likely to be re-classified in the DSM-V under the heading of disruptive, impulse control, and conduct disorders.These sorts of impulse control disorders are most often treated using certain types of psychopharamcological interventions (e.g. antidepressants) and behavioral treatments like cognitive behavioral therapy.

Theories of impulsivity
Ego (cognitive) depletion
According to the ego (or cognitive) depletion theory of impulsivity, self-control refers to the capacity for altering ones own responses, especially to bring them into line with standards such as ideals, values, morals, and social expectations, and to support the pursuit of long-term goals. Self-control enables a person to restrain or override one response, thereby making a different response possible.
A major tenet of the theory is that engaging in acts of self-control draws from a limited "reservoir" of self-control that, when depleted, results in reduced capacity for further self-regulation. Self-control is viewed as analogous to a muscle: Just as a muscle requires strength and energy to exert force over a period of time, acts that have high self-control demands also require strength and energy to perform. Similarly, as muscles become fatigued after a period of sustained exertion and have reduced capacity to exert further force, self-control can also become depleted when demands are made of self-control resources over a period of time. Baumeister and colleagues termed the state of diminished self-control strength ego depletion (or cognitive depletion).The strength model of self-control asserts that:

Just as exercise can make muscles stronger, there are signs that regular exertions of self-control can improve willpower strength. These improvements typically take the form of resistance to depletion, in the sense that performance at self-control tasks deteriorates at a slower rate. Targeted efforts to control behavior in one area, such as spending money or exercise, lead to improvements in unrelated areas, such as studying or household chores. And daily exercises in self-control, such as improving posture, altering verbal behavior, and using ones nondominant hand for simple tasks, gradually produce improvements in self-control as measured by laboratory tasks. The finding that these improvements carry over into tasks vastly different from the daily exercises shows that the improvements are not due to simply increasing skill or acquiring self-efficacy from practice.
Just as athletes begin to conserve their remaining strength when their muscles begin to tire, so do self-controllers when some of their self-regulatory resources have been expended. The severity of behavioral impairment during depletion depends in part on whether the person expects further challenges and demands. When people expect to have to exert self-control later, they will curtail current performance more severely than if no such demands are anticipated.
Consistent with the conservation hypothesis, people can exert self-control despite ego depletion if the stakes are high enough. Offering cash incentives or other motives for good performance counteracts the effects of ego depletion. This may seem surprising but in fact it may be highly adaptive. Given the value and importance of the capacity for self-control, it would be dangerous for a person to lose that capacity completely, and so ego depletion effects may occur because people start conserving their remaining strength. When people do exert themselves on the second task, they deplete the resource even more, as reflected in severe impairments on a third task that they have not anticipated.Empirical tests of the ego-depletion effect typically adopt dual-task paradigm. Participants assigned to an experimental ego-depletion group are required to engage in two consecutive tasks requiring self-control. Control participants are also required to engage in two consecutive tasks, but only the second task requires self-control. The strength model predicts that the performance of the experimental-group on the second self-control task will be impaired relative to that of the control group. This is because the finite self-control resources of the experimental participants will be diminished after the initial self-control task, leaving little to draw on for the second task.The effects of ego depletion do not appear to be a product of mood or arousal. In most studies, mood and arousal has not been found to differ between participants who exerted self-control and those who did not. Likewise, mood and arousal was not related to final self-control performance. The same is true for more specific mood items, such as frustration, irritation, annoyance, boredom, or interest as well. Feedback about success and failure of the self-control efforts does not appear to affect performance. In short, the decline in self-control performance after exerting self-control appears to be directly related to the amount of self-control exerted and cannot be easily explained by other, well-established psychological processes.

Automatic vs. controlled processes/cognitive control
Dual process theory states that mental processes operate in two separate classes: automatic and controlled.  In general, automatic processes are those that are experiential in nature, occur without involving higher levels of cognition, and are based on prior experiences or informal heuristics. Controlled decisions are effortful and largely conscious processes in which an individual weighs alternatives and makes a more deliberate decision.
Automatic Process:  Automatic processes have four main features. They occur unintentionally or without a conscious decision, the cost of the decision is very low in mental resources, they cannot be easily stopped, and they occur without conscious thought on the part of the individual making them.
Controlled Process:  Controlled processes also have four main features that are very close to the opposite in spectrum from their automatic counterparts.  Controlled processes occur intentionally, they require the expenditure of cognitive resources, the individual making the decision can stop the process voluntarily, and the mental process is a conscious one.Dual process theories at one time considered any single action/thought as either being automatic or controlled.  However, currently they are seen as operating more along a continuum as most impulsive actions will have both controlled and automatic attributes.  Automatic processes are classified according to whether they are meant to inhibit or to facilitate a thought process. For example, in one study researchers offered individuals a choice between a 1 in 10 chance of winning a prize and a 10 in 100 chance. Many participants chose one of the choices over the other without identifying that the chances inherent in each were the same as they saw either only 10 chances total as more beneficial, or of having 10 chances to win as more beneficial. In effect impulsive decisions can be made as prior information and experiences dictate one of the courses of action is more beneficial when in actuality careful consideration would better enable the individual to make a more informed and improved decision.

Intertemporal choice
Intertemporal choice is defined as "decisions with consequences that play out over time".  This is often assessed using the relative value people assign to rewards at different points in time, either by asking experimental subjects to choose between alternatives or examining behavioral choices in a naturalistic setting.Intertemporal choice is commonly measured in the laboratory using a "delayed discounting" paradigm, which measures the process of devaluing rewards and punishments that happen in the future. In this paradigm, subjects must choose between a smaller reward delivered soon and a larger reward delivered at a delay in the future.  Choosing the smaller-sooner reward is considered impulsive. By repeatedly making these choices, indifference points can be estimated. For example, if someone chose $70 now over $100 in a week, but chose the $100 in a week over $60 now, it can be inferred that they are indifferent between $100 in a week and an intermediate value between $60 and $70.  A delay discounting curve can be obtained for each participant by plotting their indifference points with different reward amounts and time delays.  Individual differences in discounting curves are affected by personality characteristics such as self-reports of impulsivity and locus of control; personal characteristics such as age, gender, IQ, race, and culture; socioeconomic characteristics such as income and education; and many other variables. to drug addiction. Lesions of the nucleus accumbens core subregion or basolateral amygdala produce shifts towards choosing the smaller-sooner reward, suggesting the involvement of these brain regions in the preference for delayed reinforcers.  There is also evidence that the orbitofrontal cortex is involved in delay discounting, although there is currently debate on whether lesions in this region result in more or less impulsivity.Economic theory suggests that optimal discounting involves the exponential discounting of value over time.  This model assumes that people and institutions should discount the value of rewards and punishments at a constant rate according to how delayed they are in time.  While economically rational, recent evidence suggests that people and animals do not discount exponentially.  Many studies suggest that humans and animals discount future values according to a hyperbolic discounting curve where the discount factor decreases with the length of the delay (for example, waiting from today to tomorrow involves more loss of value than waiting from twenty days to twenty-one days).  Further evidence for non-constant delay discounting is suggested by the differential involvement of various brain regions in evaluating immediate versus delayed consequences.  Specifically, the prefrontal cortex is activated when choosing between rewards at a short delay or a long delay, but regions associated with the dopamine system are additionally activated when the option of an immediate reinforcer is added. Additionally, intertemporal choices differ from economic models because they involve anticipation (which may involve a neurological "reward" even if the reinforcer is delayed), self-control (and the breakdown of it when faced with temptations), and representation (how the choice is framed may influence desirability of the reinforcer), none of which are accounted for by a model that assumes economic rationality.One facet of intertemporal choice is the possibility for preference reversal, when a tempting reward becomes more highly valued than abstaining only when immediately available.  For example, when sitting home alone, a person may report that they value the health benefit of not smoking a cigarette over the effect of smoking one.  However, later at night when the cigarette is immediately available, their subjective value of the cigarette may rise and they may choose to smoke it.A theory called the "primrose path" is intended to explain how preference reversal can lead to addiction in the long run. As an example, a lifetime of sobriety may be more highly valued than a lifetime of alcoholism, but, at the same time, one drink now may be more highly valued than not drinking now.  Because it is always "now," the drink is always chosen, and a paradoxical effect occurs whereby the more-valued long-term alternative is not achieved because the more-valued short-term alternative is always chosen. This is an example of complex ambivalence, when a choice is made not between two concrete alternatives but between one immediate and tangible alternative (i.e. having a drink) and one delayed and abstract alternative (i.e. sobriety).
Similarities between humans and non-human animals in intertemporal choice have been studied.  Pigeons and rats also discount hyperbolically; tamarin monkeys do not wait more than eight seconds to triple the amount of a food reward. The question arises as to whether this is a difference of homology or analogy—that is, whether the same underlying process underlies human-animal similarities or whether different processes are manifesting in similar patterns of results.

Inhibitory control
Inhibitory control, often conceptualized as an executive function, is the ability to inhibit or hold back a prepotent response. It is theorized that impulsive behavior reflects a deficit in this ability to inhibit a response; impulsive people may find it more difficult to inhibit action whereas non-impulsive people may find it easier to do so. There is evidence that, in normal adults, commonly used behavioral measures of inhibitory control correlate with standard self-report measures of impulsivity.Inhibitory control may itself be multifaceted, evidenced by numerous distinct inhibition constructs that can be measured in different ways, and relate to specific types of psychopathology. Joel Nigg developed a useful working taxonomy of these different types of inhibition, drawing heavily from the fields of cognitive and personality psychology Niggs eight proposed types of  inhibition include the following:

Executive Inhibition
Interference control
Suppression of a stimulus that elicits an interfering response, enabling a person to complete the primary response.  Interference control can also refer to suppressing distractors.Interference control has been measured using cognitive tasks like the stroop test, flanker tasks, dual task interference, and priming tasks.  Personality researchers have used the Rothbart effortful control measures and the conscientiousness scale of the Big Five as inventory measures of interference control.  Based on imaging and neural research it is theorized that the anterior cingulate, the dorsolateral prefrontal/premotor cortex, and the basal ganglia are related to interference control.

Cognitive inhibition
Cognitive inhibition is the suppression of unwanted or irrelevant thoughts to protect working memory and attention resources.Cognitive inhibition is most often measured through tests of directed ignoring, self-report on ones intrusive thoughts, and negative priming tasks.  As with interference control, personality psychologists have measured cognitive inhibition using the Rothbart Effortful Control scale and the Big Five Conscientiousness scale. The anterior cingulate, the prefrontal regions, and the association cortex seem to be involved in cognitive inhibition.

Behavioral inhibition
Behavioral Inhibition is the suppression of prepotent response.Behavioral inhibition is usually measured using the Go/No Go task, Stop signal task, and reports of suppression of attentional orienting.  Surveys that are theoretically relevant to behavioral inhibition include the Rothbart effortful control scale, and the Big Five Conscientiousness dimension. The rationale behind the use of behavioral measures like the Stop signal task is that "go" processes and "stop processes" are independent, and that, upon "go" and "stop" cues, they "race" against each other; if the go process wins the race, the prepotent response is executed, whereas if the stop processes wins the race, the response is withheld. In this context, impulsivity is conceptualized as a relatively slow stop process. The brain regions involved in behavioral inhibition appear to be the lateral and orbital prefrontal regions along with premotor processes.

Oculomotor Inhibition
Oculomotor Inhibition is the effortful suppression of reflexive saccade.Oculomotor inhibition is tested using antisaccade and oculomotor tasks. Also, the Rothbart effortful control measure and the Big Five Conscientiousness dimension are thought to tap some of the effortful processes underlying the ability to suppress saccade.  The frontal eye fields and the dorsolateral prefrontal cortex are involved in oculomotor inhibition.

Motivational inhibition
In response to punishment
Motivational inhibition and response in the face of punishment can be measured using tasks tapping inhibition of primary response, modified go/no go tasks, inhibition of competing response, and emotional Stroop tasks. Personality psychologists also use the Gray behavioral inhibition system measure, the Eysenck scale for neurotic introversion, and the Zuckerman Neuroticism-Anxiety scale.  The  Septal-hippocampal formation, cingulate, and motor systems seem to be the brain areas most involved in response to punishment.

In response to novelty
Response to novelty has been measured using the Kagan behavioral inhibition system measure and scales of neurotic introversion.  The amygdaloid system is implicated in novelty response.

Automatic inhibition of attention
Recently inspected stimuli
Suppression of recently inspected stimuli for both attention and oculomotor saccade is usually measured using attentional and oculomotor inhibition of return tests. The superior colliculus and the midbrain, oculomotor pathway are involved in suppression of stimuli.

Neglected stimuli
Information at locations that are not presently being attended to is suppressed, while attending elsewhere.This involves measures of covert attentional orienting and neglect, along with personality scales on neuroticism.  The posterior association cortex and subcortical pathways are implicated in this sort of inhibition.

Action/Inaction goals
Recent psychology research also yields out the condition of impulsivity in relation to peoples general goal setting. It is possible these action and inaction goals are underlying peoples behavioral differences in their daily lives since they can demonstrate "patterns comparable to natural variation in overall activity levels". More specifically, the level of impulsivity and mania people have might positive correlated with favorable attitudes about and goals of general action while negatively respond to favorable attitudes about and goals of general inaction.

Assessment of impulsivity
Personality tests and reports
Barratt Impulsiveness Scale
The Barratt Impulsiveness Scale (BIS) is one of the oldest and most widely used measures of impulsive personality traits. The first BIS was developed in 1959 by Dr. Ernest Barratt. It has been revised extensively to achieve two major goals: (1) to identify a set of "impulsiveness" items that was orthogonal to a set of "anxiety" items as measured by the Taylor Manifest Anxiety Scale (MAS) or the Cattell Anxiety Scale, and (2) to define impulsiveness within the structure of related personality traits like Eysencks Extraversion dimension or Zuckermans Sensation-Seeking dimension, especially the disinhibition subfactor. The BIS-11 with 30 items was developed in 1995. According to Patton and colleagues, there are 3 subscales (Attentional Impulsiveness, Motor Impulsiveness, and Non-Planning Impulsiveness) with six factors:
Attention: "focusing on a task at hand".
Motor impulsiveness: "acting on the spur of the moment".
Self-control: "planning and thinking carefully".
Cognitive complexity: "enjoying challenging mental tasks".
Perseverance: "a consistent life style".
Cognitive instability: "thought insertion and racing thoughts".

Eysenck Impulsiveness Scale
The Eysenck Impulsiveness Scale (EIS) is a 54-item yes/no questionnaire designed to measure impulsiveness. Three subscales are computed from this measure: Impulsiveness, Venturesomeness, and Empathy. Impulsiveness is defined as "behaving without thinking and without realizing the risk involved in the behavior". Venturesomeness is conceptualized as "being conscious of the risk of the behavior but acting anyway" The questionnaire was constructed through factor analysis to contain items that most highly loaded on impulsiveness and venturesomeness. The EIS is a widely used and well-validated measure.

Dickman Impulsivity Inventory
The Dickman Impulsivity Inventory was first developed in 1990 by Scott J. Dickman. This scale is based on Dickmans proposal that there are two types of impulsivity that are significantly different from one another. This includes functional impulsivity which is characterized by quick decision making when it is optimal, a trait that is often considered to be a source of pride. The scale also includes dysfunctional impulsivity which is characterized by making quick decisions when it is not optimal. This type of impulsivity is most often associated with life difficulties including substance abuse problems and other negative outcomes.This scale includes 63 items of which 23 are related to dysfunctional impulsivity, 17 are related to functional impulsivity, and 23 are filler questions that relate to neither construct. This scale has been developed into a version for use with children as well as into several languages. Dickman showed there is no correlation between these two tendencies across individuals, and they also have different cognitive correlates.

UPPS Impulsive Behavior Scale
The UPPS Impulsive Behavior Scale is a 45-item self-report questionnaire that was designed to measure impulsivity across dimensions of the Five Factor Model of personality. The UPPS includes 4 sub-scales: lack of premeditation, urgency, lack of perseverance, and sensation-seeking.
UPPS-P Impulsive Behavior Scale (UPPS-P) is a revised version of the UPPS, including 59 items. It assesses an additional personality pathway to impulsive behavior, Positive Urgency, in addition to the four pathways assessed in the original version of the scale: Urgency (now Negative Urgency), (lack of) Premeditation, (lack of) Perseverance, and Sensation Seeking
UPPS-P short version (UPPS-Ps) is  20-item scale that evaluates five different impulsivity facets (4 items per dimension).
UPPS-R Interview is a semi-structured interview that measures the degree to which individuals exhibit the various components of impulsivity assessed by the UPPS-P.

Lifetime History of Impulsive Behaviors
Lifetime History of Impulsive Behaviors (LHIB)  is a 53-item questionnaire designed to assess lifetime history of impulsive behavior (as opposed to impulsive tendencies) as well as the level of distress and impairment associated with these behaviors. The assessment battery was designed to measure the following six dimensions: (a) impulsivity, (b) sensation seeking, (c) trait anxiety, (d) state depression, (e) empathy, and (f) social desirability. The LHIB consists of scales for clinically significant impulsivity, non-clinically significant impulsivity, and impulsivity related distress/impairment.

Behavioral Inhibition System/Behavioral Activation System
Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) was developed based on the Grays biopsychological theory of personality which suggests that there are two general motivational systems that underlie behavior and affect: BIS and BAS. This 20-item self-report questionnaire is designed to assess dispositional BIS and BAS sensitivities.

Impulsive/Premeditated Aggression Scale
Impulsive/Premeditated Aggression Scale (IPAS) is a 30-item self-report questionnaire. Half of the items describe impulsive aggression and half the items describe premeditated aggression. Aggressive behavior has traditionally been classified into two distinct subtypes, impulsive or premeditated. Impulsive aggression is defined as a hair-trigger aggressive response to provocation with loss of behavioral control. Premeditated aggression is defined as a planned or conscious aggressive act, not spontaneous or related to an agitated state. The IPAS is designed to characterize aggressive behavior as predominately impulsive or predominately premeditated in nature. Those subjects who clustered on the impulsive factor showed a broad range of emotional and cognitive impairments; those who clustered on the premeditated factor showed a greater inclination for aggression and anti-social behaviour.

Padua Inventory
The Padua Inventory (PI) consists of 60 items describing common obsessional and compulsive behavior and allows investigation of such problems in normal and clinical subjects.

Behavioral paradigms
A wide variety of behavioral tests have been devised for the assessment of impulsivity in both clinical and experimental settings. While no single test is a perfect predictor or a sufficient replacement for an actual clinical diagnosis, when used in conjunction with parent/teacher reports, behavioral surveys, and other diagnostic criteria, the utility of behavioral paradigms lies in their ability to narrow in on specific, discrete aspects of the impulsivity umbrella. Quantifying specific deficits is of use to the clinician and the experimenter, both of whom are generally concerned with obtaining objectively measurable treatment effects.

Marshmallow test
One widely recognizable test for impulsivity is the delay of gratification paradigm commonly known as the marshmallow test. Developed in the 1960s to assess willpower and self-control in preschoolers, the marshmallow test consists of placing a single marshmallow in front of a child and informing them that they will be left alone in the room for some duration. The child is told that if the marshmallow remains uneaten when the experimenter returns, they will be awarded a second marshmallow, both of which can then be eaten.Despite its simplicity and ease of administration, evidence from longitudinal studies suggests that the number of seconds preschoolers wait to obtain the second marshmallow is predictive of higher SAT scores, better social and emotional coping in adolescence, higher educational achievement, and less cocaine/crack use.

Delay discounting
Like the marshmallow test, delay discounting is also a delay of gratification paradigm. It is designed around the principle that the subjective value of a reinforcer decreases, or is discounted, as the delay to reinforcement increases. Subjects are given varying choices between smaller, immediate rewards and larger, delayed rewards. By manipulating reward magnitude and/or reward delay over multiple trials, indifference points can be estimated whereby choosing the small, immediate reward, or the large, delayed reward are about equally likely. Subjects are labeled impulsive when their indifference points decline more steeply as a function of delay compared to the normal population (i.e. greater preference for immediate reward). Unlike the marshmallow test, delay discounting does not require verbal instruction and can be implemented on non-human animals.

Go/no-go and stop-signal reaction time tasks
Two common tests of response inhibition used in humans are the go/no-go task, and a slight variant known as the stop-signal reaction time (SSRT) test. During a go/no-task, the participant is trained over multiple trials to make a particular response (e.g., a key-press) when presented with a go signal. On some trials, a stop signal is presented just prior to, or simultaneously with the go signal, and the subject must inhibit the impending response.
The SSRT test is similar, except that the stop signal is presented after the go signal. This small modification increases the difficulty of inhibiting the go response, because the participant has typically already initiated the go response by the time the stop signal is presented. The participant is instructed to respond as fast as possible to the go signal while maintaining the highest possible inhibition accuracy (on no-go trials). During the task, the time at which the stop signal is presented (the stop signal delay or SSD) is dynamically adjusted to match the time after the go signal at which the participant is just able/unable to inhibit their go response. If the participant fails to inhibit their go response, the stop signal is moved slightly closer to the original go signal, and if the participant successfully inhibits their go response, the stop signal is moved slightly ahead in time. The SSRT is thus measured as the average go response time minus the average stop signal presentation time (SSD).

Balloon Analogue Risk Task
The balloon analogue risk task (BART) was designed to assess risk-taking behavior. Subjects are presented with a computer depiction of a balloon that can be incrementally inflated by pressing a response key. As the balloon inflates, the subject accumulates rewards with each new key-press. The balloon is programmed with a constant probability of popping. If the balloon pops, all rewards for that balloon are lost, or the subject may choose to stop inflating and bank the reward for that balloon at any time. Therefore, more key-presses equate to greater reward, but also greater probability of popping and cancelling rewards for that trial. The BART assumes that those with an affinity for risk-taking are more likely to pop the balloon, earning less reward overall than the typical population.

Iowa Gambling Task
The Iowa gambling task  (IGT) is a test originally meant to measure decision making specifically within individuals who have ventromedial prefrontal cortex damage. The concept of impulsivity as relates to the IGT is one in which impulsive decisions are a function of an individuals lack of ability to make rational decisions over time due to an over amplification of emotional/somatic  reward. In the IGT individuals are provided four decks of cards to choose from.  Two of these decks provide much higher rewards but the deductions are also much higher while the second two decks have lower rewards per card but also much lower deductions.  Over time anyone who chooses predominantly from the high rewards decks will lose money while those who choose from the smaller rewards decks will gain money.
The IGT uses hot and cold processes in its concept of decision making.  Hot decision making involves emotional responses to the material presented based on motivation related to reward and punishment.  Cold processes occur when an individual uses rational cognitive determinations when making decisions.  Combined an individual should gain a positive emotional reaction when choices have beneficial consequences and will have negative emotional responses tied to choices that have greater negative consequences.  In general, healthy responders to the IGT will begin to drift to the lower gain decks as they realize that they are gaining more money than they lose both through an ability to recognize that one is more consistently providing rewards as well as through the emotions related to winning consistently.  However, those who have emotional deficits will fail to recognize that they are losing money over time and will continue to be more influenced by the exhilaration of higher value rewards without being influenced by the negative emotions of the loses associated with them.For more information concerning these process refer to the Somatic marker hypothesis

Differential Reinforcement of Low Response Rate Task
Differential reinforcement of low response rate (DRL) described by Ferster and Skinner is used to encourage low rates of responding. It is derived from research in operant conditioning that provides an excellent opportunity to measure the hyperactive childs ability to inhibit behavioral responding. Hyperactive children were relatively unable to perform efficiently on the task, and this deficit endured regardless of age, IQ, or experimental condition. Therefore, it can be used to discriminate accurately between teacher rated and parent rated hyperactive and nonhyperactive children. In this procedure, responses that occur before a set time interval has passed are not reinforced and reset the time required between behaviors.In a study, a child was taken to the experimental room and told that they were going to play a game in which they had a chance to win a lot of M&Ms.  Every time they made the light of the reward indicator by pressing a red button, they would earn an M&Ms. However, they had to wait a while (6 seconds) before they could press it to get another point. If they had pressed the button too soon, then they would have not gotten a point, and the light would not go on, and they had to wait a while before they could press it to get another point.Researchers have also observed that subjects in a time-based situation will often engage in a sequence or chain of behaviors between reinforceable responses. This is because this collateral behavior sequence helps the subject "wait out" the required temporal delay between responses.

Other
Other common impulsivity tasks include the Continuous performance task (CPT), 5-choice serial reaction time task (5-CSRTT), Stroop task, and Matching Familiar Figures Task.

Pharmacology and neurobiology
Neurobiological findings
Although the precise neural mechanisms underlying disorders of impulse control are not fully known, the prefrontal cortex (PFC) is the brain region most ubiquitously implicated in impulsivity.  Damage to the prefrontal cortex has been associated with difficulties preparing to act, switching between response alternatives, and inhibiting inappropriate responses. Recent research has uncovered additional regions of interest, as well as highlighted particular subregions of the PFC, that can be tied to performance in specific behavioral tasks.

Delay discounting
Excitotoxic lesions in the nucleus accumbens core have been shown to increase preference for the smaller, immediate reward, whereas lesions to the nucleus accumbens shell have had no observable effect. Additionally, lesions of the basolateral amygdala, a region tied closely to the PFC, negatively affect impulsive choice similarly to what is observed in the nucleus accumbens core lesions. Moreover, dorsal striatum may also be involved in impulsive choice in an intricate manner.

Go/No-go and Stop-signal reaction time test
The orbitofrontal cortex is now thought to play a role in disinhibiting, and injury to other brain structures, such as to the right inferior frontal gyrus, a specific subregion of the PFC, has been associated with deficits in stop-signal inhibition.

5-Choice Serial Reaction Time Task (5-CSRTT) and Differential Reinforcement of Low rates (DRL)
As with delay discounting, lesion studies have implicated the core region of the nucleus accumbens in response inhibition for both DRL and 5-CSRTT.  Premature responses in the 5-CSRTT may also be modulated by other systems within the ventral striatum. In the 5-CSRTT, lesions of the anterior cingulate cortex have been shown to increase impulsive responding, and lesions to the prelimbic cortex impair attentional performance.

Iowa Gambling Task
Patients with damage to the ventromedial frontal cortex exhibit poor decision-making and persist in making risky choices in the Iowa Gambling Task.

Neurochemical and pharmacological findings
The primary pharmacological treatments for ADHD are methylphenidate (Ritalin) and amphetamine. Both methylphenidate and amphetamines block re-uptake of dopamine and norepinephrine into the pre-synaptic neuron, acting to increase post-synaptic levels of dopamine and norepinephrine. Of these two monoamines, increased availability of dopamine is considered the primary cause for the ameliorative effects of ADHD medications, whereas increased levels of norepinephrine may be efficacious only to the extent that it has downstream, indirect effects on dopamine.
The effectiveness of dopamine re-uptake inhibitors in treating the symptoms of ADHD has led to the hypothesis that ADHD may arise from low tonic levels of dopamine (particularly in the fronto-limbic circuitry), but evidence in support of this theory is mixed.

Genetics
There are several difficulties when it comes to trying to identify a gene for complex traits such as impulsivity, such as genetic heterogeneity.  Another difficulty is that the genes in question might sometimes show incomplete penetrance, "where a given gene variant does not always cause the phenotype".  Much of the research on the genetics of impulsivity-related disorders, such as ADHD, is based on family or linkage studies. There are several genes of interest that have been studied in an attempt to find the major genetic contributors to impulsivity.  Some of these genes are:

DAT1  is the dopamine transporter gene which is responsible for the active reuptake of dopamine from the neural synapse. DAT1 polymorphisms have been shown to be linked to hyperactivity and ADHD.
DRD4 is the dopamine D4 receptor gene and is associated with ADHD and novelty seeking behaviors. It has been proposed that novelty seeking is associated with impulsivity.  Mice deficient for DRD4 have shown less behavioral responses to novelty.
5HT2A is the serotonin receptor gene.  The serotonin 2A receptor gene has been associated with both hyper locomotion, ADHD, as well as impulsivity.  Subjects with a particular polymorphism of the 5HT2A gene made more commission errors during a punishment-reward condition in a go/no-go task.
HTR2B a serotonin receptor gene.
CTNNA2 encodes for a brain-expressed α-catenin that has been associated with Excitement-Seeking in a genome-wide association study (GWAS) of 7860 individuals.

Intervention
Interventions to impact impulsivity generally
While impulsivity can take on pathological forms (e.g. substance use disorder, ADHD), there are less severe, non-clinical forms of problematic impulsivity in many peoples daily lives.  Research on the different facets of impulsivity can inform small interventions to change decision making and reduce impulsive behavior For example, changing cognitive representations of rewards (e.g. making long term rewards seem more concrete) and/or creating situations of "precommitment" (eliminating the option of changing ones mind later)  can reduce the preference for immediate reward seen in delay discounting.

Brain training
Brain training interventions include laboratory-based interventions (e.g. training using tasks like go/no go) as well as community, family, and school based interventions that are ecologically valid (e.g. teaching techniques for regulating emotions or behaviors) and can be used with individuals with non-clinical levels of impulsivity.  Both sorts of interventions are aimed at improving executive functioning and self-control capacities, with different interventions specifically targeting different aspects of executive functioning like inhibitory control, working memory, or attention. Emerging evidence suggests that brain training interventions may succeed in impacting executive function, including inhibitory control. Inhibitory control training specifically is accumulating evidence that it can help individuals resist temptation to consume high calorie food and drinking behavior. Some have voiced concerns that  the favorable results of studies testing working memory training should be interpreted with caution, claiming that conclusions regarding changes to abilities are measured using single tasks, inconsistent use of working memory tasks, no-contact control groups, and subjective measurements of change.

Treatment of specific disorders of impulsivity
Behavioral, psychosocial, and psychopharmacological treatments for disorders involving impulsivity are common.

Psychopharmacological intervention
Psychopharmacological intervention in disorders of impulsivity has shown evidence of positive effects; common pharmacological interventions include the use of stimulant medication, selective serotonin reuptake inhibitors (SSRIs) and other antidepressants. ADHD has a well-established evidence base supporting the use of stimulant medication for the reduction of ADHD symptoms. Pathological gambling has also been studied in drug trials, and there is evidence that gambling is responsive to SSRIs and other antidepressants.  Evidence based pharmacological treatment for trichotillomania is not yet available, with mixed results of studies investigating the use of SSRIs, though cognitive behavioral therapy has shown positive effects. Intermittent explosive disorder is most often treated with mood stabilizers, SSRIs, beta blockers, alpha agonists, and anti-psychotics (all of which have shown positive effects). There is evidence that some pharmacological interventions are efficacious in treating substance-use disorders, though their use can depend on the type of substance that is abused.  Pharmacological treatments for substance-use disorders include  acamprosate, buprenorphine, disulfiram, LAAM, methadone, and naltrexone.

Behavioral interventions
Behavioral interventions also have a fairly strong evidence base in impulse-control disorders. In ADHD, the behavioral interventions of behavioral parent training, behavioral classroom management, and intensive peer-focused behavioral interventions in recreational settings meet stringent guidelines qualifying them for evidence based treatment status. In addition, a recent meta-analysis of evidence-based ADHD treatment found organization training to be a well-established treatment method. Empirically validated behavioral treatments for substance use disorder are fairly similar across substance use disorders, and include behavioral couples therapy, CBT, contingency management, motivational enhancement therapy, and relapse prevention.  Pyromania and kleptomania are understudied (due in large part to the illegality of the behaviors), though there is some evidence that psychotherapeutic interventions (CBT, short term counseling, day treatment programs) are efficacious in treating pyromania, while kleptomania seems to be best addressed using SSRIs.  Additionally, therapies including CBT, family therapy, and social skill training have shown positive effects on explosive aggressive behaviors.

See also
Affect
ADHD
Addiction
Deferred gratification
Drive theory
Emotion
Feeling
Instinct
Impulse control disorder
Sensation seeking
Novelty seeking
Alternative five model of personality

References
Further reading
Evenden, J. L. (21 October 1999). "Varieties of impulsivity". Psychopharmacology. 146 (4): 348–361. doi:10.1007/PL00005481. PMID 10550486. S2CID 5972342.
Hollander, E.; Rosen, J. (March 2000). "Impulsivity". Journal of Psychopharmacology. 14 (2_suppl1): S39–S44. doi:10.1177/02698811000142S106. PMID 10888030. S2CID 243171966.
Moeller, F. Gerard; Barratt, Ernest S.; Dougherty, Donald M.; Schmitz, Joy M.; Swann, Alan C. (November 2001). "Psychiatric Aspects of Impulsivity" </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Intraventricular hemorrhage and can you explain it in depth? [/INST] Intraventricular hemorrhage (IVH), also known as intraventricular bleeding, is a bleeding into the brains ventricular system, where the cerebrospinal fluid is produced and circulates through towards the subarachnoid space.  It can result from physical trauma or from hemorrhagic stroke.
30% of intraventricular hemorrhage (IVH) are primary, confined to the ventricular system and typically caused by intraventricular trauma, aneurysm, vascular malformations, or tumors, particularly of the choroid plexus. However 70% of IVH are secondary in nature, resulting from an expansion of an existing intraparenchymal or subarachnoid  hemorrhage. Intraventricular hemorrhage has been found to occur in 35% of moderate to severe traumatic brain injuries.  Thus the hemorrhage usually does not occur without extensive associated damage, and so the outcome is rarely good.

Symptoms
Adults
Symptoms of IVH are similar to other intracerebral hemorrhages and include sudden onset of headache, nausea and vomiting, together with an alteration
of the mental state and/or level of consciousness. Focal neurological signs are either minimal or absent, but focal and/or generalized seizures may occur. Xanthochromia, yellow-tinged CSF, is the rule.

Infants
Some infants are asymptomatic and others may present with hard to detect abnormalities of consciousness, muscle tone, breathing, movements of their eyes, and body movements.

Causes
Adults
Causes of IVH in adults include physical trauma or from hemorrhagic stroke.

Infants
Infants that are preterm and very low birth weight are also at high risk. IVH in the preterm brain usually arises from the germinal matrix whereas IVH in the term infants originates from the choroid plexus. However, it is particularly common in premature infants or those of very low birth weight.  The cause of IVH in premature infants, unlike that in older infants, children or adults, is rarely due to trauma.  Instead it is thought to result from changes in perfusion of the delicate cellular structures that are present in the growing brain, augmented by the immaturity of the cerebral circulatory system, which is especially vulnerable to hypoxic ischemic encephalopathy.  The lack of blood flow results in cell death and subsequent breakdown of the blood vessel walls, leading to bleeding.  While this bleeding can result in further injury, it is itself a marker for injury that has already occurred.  Most intraventricular hemorrhages occur in the first 72 hours after birth. The risk is increased with use of extracorporeal membrane oxygenation in preterm infants. Congenital cytomegalovirus infection can be an important cause.

Mechanism
Diagnosis
Diagnosis can be confirmed by the presence of blood inside the ventricles on CT.

Infants
In term and preterm infants with IVH, the amount of bleeding varies. IVH is often described in four grades:
Grade I - bleeding occurs just in the germinal matrix
Grade II - bleeding also occurs inside the ventricles, but they are not enlarged
Grade III - ventricles are enlarged by the accumulated blood
Grade IV - bleeding extends into the brain tissue around the ventriclesGrades I and II are most common, and often there are no further complications. Grades III and IV are the most serious and may result in long-term brain injury to the infant. After a grade III or IV IVH, blood clots may form which can block the flow of cerebrospinal fluid, leading to increased fluid in the brain (hydrocephalus).

Prevention
Head positioning in very preterm infants has been suggested as an approach to prevent germinal matrix haemorrhage; however, further research is required to determine the effectiveness at reducing mortality and the most appropriate positioning technique. Approaches include bed tilting, supine mid-line head positioning, supine head rotation 90 degrees, prone mid-line head positioning, head tiling.

Treatment
Treatment focuses on monitoring and should be accomplished with inpatient floor service for individuals responsive to commands or neurological ICU observation for those with impaired levels of consciousness. Extra attention should be placed on intracranial pressure (ICP) monitoring via an intraventricular catheter and medications to maintain ICP, blood pressure, and coagulation. In more severe cases an external ventricular drain may be required to maintain ICP and evacuate the hemorrhage, and in extreme cases an open craniotomy may be required. In cases of unilateral IVH with small intraparenchymal hemorrhage the combined method of stereotaxy and open craniotomy has produced promising results.

Infants
There have been various therapies employed into preventing the high rates of morbidity and mortality, including diuretic therapy, repeated lumbar puncture, streptokinase therapy  and a combination novel intervention called DRIFT (drainage, irrigation and fibrinolytic therapy). More research is required, in the form of high quality randomized controlled trials, to determine the safety, dosing, and effectiveness of prophylactic heparin and antithrombin treatment for preterm neonates.

Prognosis
In infants, germinal matrix haemorrhage is associated with cerebral palsy, problems with cognition, and hydrocephalus. With improved technological advances in science and medicine, survival for preterm infants with this type of neurological disorder has improved and less preterm infants with germinal matrix haemorrhage have severe cerebral palsy. An estimated 15% of preterm infants who survive develop cerebral palsy and 27% of the infants who survive experience moderate to severe neurosensory deficits by the time they reach 18–24 months old.Prognosis is very poor when IVH results from intracerebral hemorrhage related to high blood pressure and is even worse when hydrocephalus follows.  It can result in dangerous increases in ICP and can cause potentially fatal brain herniation </s>