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 and strategies for success.
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 in instances of acquired brain injury and neurodegenerative diseases. Neurobiological findings suggest that there are specific brain regions involved in impulsive behavior,
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 (reduce its subjective value to them) at higher rates than those without, and that the presence of gambling and alcohol abuse lead to additive effects on discounting.
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.
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 abuse disorders.
The precise genetic and environmental factors contributing to ADHD are relatively unknown, but 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.
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.
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 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.Loxton, N.J., Dawe, S. (2004). Alcohol abuse and dysfunctional eating in women: The contribution of reward and punishment sensitivity and family of origin. In press. As cited in:
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.
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.
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 Addiction. In fact, the ICD classification is likely to change with the release of the DSM-5 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-5 within the obsessive-compulsive and related disorders category.
Pathological gambling, in contrast, seems to involve many diverse aspects of impulsivity and abnormal Reward system (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-5 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.
The strength model of self-control asserts that:
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.
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 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.
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.
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 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 Nigg's eight proposed types of inhibition include the following:
Interference control has been measured using cognitive tasks like the Stroop effect, 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 is most often measured through tests of directed ignoring, self-report on one's 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 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 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.
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.
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 childrenBrunas-Wagstaff, J., Tilley, A., Verity, M., Ford, S., & Thompson, D. (1997). Functional and dysfunctional impulsivity in children and their relationship to Eysenck's impulsiveness and venturesomeness dimensions. Personality and Individual Differences, 22(1), 19–35. 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-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.
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.
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).
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 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
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&M's. Every time they made the light of the reward indicator by pressing a red button, they would earn an M&M's. 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 Time delay between responses.
UPPS Impulsive Behavior Scale
Lifetime History of Impulsive Behaviors
Behavioral Inhibition System/Behavioral Activation System
Impulsive/Premeditated Aggression Scale
Padua Inventory
Behavioral paradigms
Marshmallow test
Delay discounting
Go/no-go and stop-signal reaction time tasks
Balloon Analogue Risk Task
Iowa Gambling Task
Differential Reinforcement of Low Response Rate Task
Other
Pharmacology and neurobiology
Neurobiological findings
Delay discounting
Go/No-go and Stop-signal reaction time test
5-Choice Serial Reaction Time Task (5-CSRTT) and Differential Reinforcement of Low rates (DRL)
Iowa Gambling Task
Neurochemical and pharmacological findings
Genetics
Intervention
Interventions to impact impulsivity generally
Brain training
Treatment of specific disorders of impulsivity
Psychopharmacological intervention
Behavioral interventions
See also
Further reading
External links
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