Impulsive Aggressive Behavior Research Articles

Emotion dysregulation and depressive symptoms mediate the association between inhibitory control difficulties and aggressive behaviour in children with ADHD.

Impulsive aggressive behaviour, although not a core symptom, is often part of the clinical presentation of attention-deficit/hyperactivity disorder (ADHD). Recently, impulsive aggression has been attributed to emotion dysregulation, which is currently conceptualised as a transdiagnostic factor and seems to contribute to the co-occurrence of other problems in ADHD. Thus, this study investigated the presence of impulsive aggressive behaviour and explored whether emotion dysregulation mediates the relationship between inhibitory control difficulties and aggressive behaviour in children with ADHD. Because ADHD may act as a risk factor for the development of other conditions, such as internalising problems, we aimed to understand whether depressive symptoms contribute to this relationship. Seventy-two children were recruited from a hospital and the community, 38 of whom had ADHD and 34 were typically developing (TD). Parents completed the Child Behaviour Checklist, the Behaviour Rating Inventory of Executive Function, and the Emotion Regulation Checklist. Simple mediation and serial mediation models were performed to test our hypotheses. Aggressive behaviour was significantly higher in ADHD children compared to TD children. Emotion dysregulation fully mediated the relationship between inhibitory control difficulties and aggressive behaviour in ADHD children. Adding depressive symptoms to the model increased the explained variance in aggressive behaviour. The main result of our study supports the role of emotion dysregulation and depressive symptoms in mediating the relationship between inhibitory control difficulties and impulsive aggressive behaviour in children with ADHD. This highlights that aggressive behaviour is, in part, a result of the inability of the child to appropriately regulate their emotions. Future interventions may be tailored to improve emotion regulation skills to address aggressive behaviour.

자폐스펙트럼장애 청소년의 감정조절과 상호작용 향상을 위한 DMT

This research aims to analyze the effects of DMT(Dance , Movement Therapy) on emotional regulation and interaction in adolescents with Autism Spectrum Disorder(ASD). The program consisted of 12 sessions, each lasting 60 minutes and conducted weekly. The research utilized video recordings of each sesstions, House-Tree-Person (HTP) test, Laban Movement Analysis (LMA) and inter-observer agreement to accumulate qualitative case study data through in-depth discussions and journals. The research findings inditcate that, following the DMT program, there were improvements in emotional regulation among adolescents with ASD. Firstly, changes in repetitive movements and expqanstion processes led to a decrease in anger, anxiety and excitement in psychological emotional regulation. Additionally, increased self-confidence in behavior and reduced anxiety towards new spaces were observed. Secondly, immature emotional regulation manifested as impulsive disruptive behavior, aggressive behavior, and repetitive behavior showed a decrease. In terms of interation among adolescents with ASD, the results showed stable improvements in voluntary and proactive participation with relational and social peer relationships. It is hoped that the results of this study will contribute to individualized research for individuals with ASD, and future research on ASD across various age groups is anticipated to continue.

Decreased oxytocin plasma levels and oxytocin receptor expression associated with aggressive behavior in aggressive-impulsive disorders

IntroductionThis study aims to enhance the understanding of the association between the phenotypic and endophenotypic characteristics of impulsive-aggressive disorders, through the study of plasma oxytocin (OXT) and oxytocin receptor (OXTR) levels in patients with borderline personality disorder (BPD) and patients with eating disorders (ED), as well as to examine the relationship of OXT system with aggressive behavior in these disorders. Methods68 patients with BPD, 67 patients with ED and 57 healthy control subjects were examined for plasma oxytocin levels and protein expression of OXTR in blood mononuclear cells. Aggressive behavior was assessed using the State-Trait Anger Expression Inventory (STAXI-2). Other self and hetero-aggressive behaviors were also evaluated through interviews. ResultsBPD and ED patients exhibited significantly lower plasma oxytocin levels than control subjects. Furthermore, BPD patients demonstrated significantly reduced expression of OXTR compared to controls. Plasma oxytocin levels negatively correlated with verbal aggression, while OXTR expression was inversely associated with the STAXI trait subscale. ConclusionsThe findings validate the existence of oxytocin system dysfunction in impulsive-aggressive disorders. They also support the link between low OXT levels in plasma and OXTR expression and the impulsive-aggressive behavior that characterizes these patients in both state and trait situations.

Attention and behavior problems in childhood predict adult financial status, health, and criminal activity: A conceptual replication and extension of Moffitt et al. (2011) using cohorts from the United States and the United Kingdom.

This study is a conceptual replication of a widely cited study by Moffitt et al. (2011) which found that attention and behavior problems in childhood (a composite of impulsive hyperactive, inattentive, and impulsive-aggressive behaviors labeled "self-control") predicted adult financial status, health, and criminal activity. Using data from longitudinal cohort studies in the United States (n = 1,168) and the United Kingdom (n = 16,506), we largely reproduced their pattern of findings that attention and behavior problems measured across the course of childhood predicted a range of adult outcomes including educational attainment (βU.S. = -0.22, βU.K. = -0.13) and spending time in jail (ORU.S. = 1.74, ORU.K. = 1.48). We found that associations with outcomes in education, work, and finances diminished in the presence of additional covariates for children's home environment and achievement but associations for other outcomes were more robust. We also found that attention and behavior problems across distinct periods of childhood were associated with adult outcomes. Specific attention and behavior problems showed some differences in predicting outcomes in the U.S. cohort, with attention problems predicting lower educational attainment and hyperactivity/impulsivity predicting ever spending time in jail. Together with the findings from Moffitt et al., our study makes clear that childhood attention and behavior problems are associated with a range of outcomes in adulthood for cohorts born in the 1950s, 1970s, and 1990s across three countries. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Impaired Punishment Learning in Conduct Disorder

Conduct disorder (CD) has been associated with deficits in the use of punishment to guide reinforcement learning (RL) and decision making. This may explain the poorly planned and often impulsive antisocial and aggressive behavior in affected youths. Here, we used a computational modeling approach to examine differences in RL abilities between CD youths and typically developing controls (TDCs). Specifically, we tested 2 competing hypotheses that RL deficits in CD reflect either reward dominance (also known as reward hypersensitivity) or punishment insensitivity (also known as punishment hyposensitivity). The study included 92 CD youths and 130 TDCs (aged 9-18 years, 48% girls) who completed a probabilistic RL task with reward, punishment, and neutral contingencies. Using computational modeling, we investigated the extent to which the 2 groups differed in their learning abilities to obtain reward and/or to avoid punishment. RL model comparisons showed that a model with separate learning rates per contingency explained behavioral performance best. Importantly, CD youths showed lower learning rates than TDCs specifically for punishment, whereas learning rates for reward and neutral contingencies did not differ. Moreover, callous-unemotional (CU) traits did not correlate with learning rates in CD. CD youths have a highly selective impairment in probabilistic punishment learning, regardless of their CU traits, whereas reward learning appears to be intact. In summary, our data suggest punishment insensitivity rather than reward dominance in CD. Clinically, the use of punishment-based intervention techniques to achieve effective discipline in patients with CD may be a less helpful strategy than reward-based techniques.

Impulsive aggression: recognition and choice of pharmacotherapy

Instrumental (controlled) aggression is observed in populations of both mentally healthy and mentally ill people. This type of aggression is not associated with any specific pathophysiological changes and cannot be considered as an independent symptom, which might be a target of pathogenetic therapy. By contrast, impulsive aggression is a paroxysm of anger, based on affectively narrowed consciousness when volition control is significantly reduced or absent. Impulsivity is different from cognate compulsivity by the loss of a stage of intellectual processing of affectively painted representations and by that the irrational attraction to action is realized involuntary, automatic. All impulsive-behavior patients are united by common pattern of neurobiological abnormalities, such as deficit of frontal inhibition of subcortical unconscious emotions and inclinations in response to relevant arousing stimuli. The results from evidence-based research, meta-analyses and Cochrane reviews of efficiency of pharmacological agents used for reduction of impulsive aggressive behavior were summarized.

Salivary cortisol awakening levels are reduced in human subjects with intermittent explosive disorder compared with controls

BackgroundThe role of the hypothalamic-pituitary-adrenal (HPA) axis in human aggressive behavior is poorly characterized, though some studies report that, unlike depression, circulating or salivary levels of cortisol are low compared with controls. MethodsIn this study, we collected three salivary cortisol levels (two in the morning and one in the evening) on three separate days in 78 adult study participants with (n = 28) and without (n = 52) prominent histories of impulsive aggressive behavior. Plasma C-Reactive Protein (CRP) and Interleukin-6 (IL-6) were also collected in most study participants. Aggressive study participants meet DSM-5 criteria for Intermittent Explosive Disorder (IED) while non-aggressive participants either had a history of a psychiatric disorder or no such history (Controls). ResultsMorning, but not evening, salivary cortisol levels were significantly lower in IED (p < 0.05), compared with control, study participants. In addition, salivary cortisol levels correlated with measures of trait anger (partial r = −0.26, p < 0.05) and aggression (partial r = −0.25, p < 0.05) but not with measures of impulsivity, psychopathy, depression, history of childhood maltreatment, or other tested variables that often differ in individuals with IED. Finally, plasma CRP levels correlated inversely with morning salivary cortisol levels (partial r = −0.28, p < 0.05); plasma IL-6 levels showed a similar, though not statistically significant (rp = −0.20, p = 0.12) relationship with morning salivary cortisol levels. ConclusionThe cortisol awakening response appears to be lower in individuals with IED compared with controls. In all study participants, morning salivary cortisol levels correlated inversely with trait anger, trait aggression, and plasma CRP, a marker of systemic inflammation. This suggests the present of a complex interaction between chronic-low level inflammation, the HPA axis, and IED that warrants further investigation.

Predictors of future suicide attempts in individuals with high suicide risk admitted to an acute psychiatry suicide intervention unit in India. A survival analysis study.

Determination of suicide vulnerability remains challenging in mental illness. Variability in risk factors identified compound its poor predictability. Longitudinal studies, offering more reliable indices of risk, from developing countries are conspicuously limited. Furthermore, research advances allude to inherent vulnerability. This study, the first of its kind from India, consequently aimed to delineate factors influencing subsequent attempts in mental illness and acute suicidality. Baseline and follow-up information (up to five years) was obtained from medical records of individuals (n=130) with acute suicidality [recent attempt (first attempt/ reattempt) and high-risk ideators]. Variables were compared between individuals with, and without subsequent suicide attempts. Time to attempt and factors influencing the same was determined using survival analysis, and Cox proportional hazard for estimating the likelihood of a subsequent suicide attempt. Median duration of follow up of the sample (n=130) was 23 months. The sample comprised of individuals with a recent attempt (first-time attempt), recent reattempt and recent high-risk ideators. Subsequent suicide attempts were noted in 30 (23.1%) patients. Baseline sociodemographic and clinical variables, including suicidality, could not differentiate individuals with a subsequent suicide attempt. Survival analysis indicated that 65% of subsequent attempts occurred within 9 months of discharge. Family history of suicide and the presence of impulsive-aggressive traits were associated with both, reduced survival time and overall increased risk of a subsequent suicide attempt. This study delineates both, the time frame associated with greatest risk, as well as individuals most likely to reattempt suicide. It thereby offers insights into potential windows of opportunity to mitigate prospective suicide risk. Strategies such as enhanced after-care and integrating specific interventions to attenuate impulsive-aggressive behaviors could be a focus to prevent future attempts, thereby decreasing rates of suicide amongst those with mental illness. Furthermore, the findings of this study reaffirm the role of factors that independently confer vulnerability to suicide. Traversing noted regional variations, the findings importantlyreinforce the distinct pathophysiological underpinnings of suicide in mental illness.

Impulsivity, aggression, and impulsive aggression in suicidality

BackgroundImpulsivity and aggression are individual differences that receive considerable attention as psychological targets in suicide prevention. Their proposed roles in predicting suicidality, however, are conflicting and they may act together under the broader psychopathology of ‘impulsive aggression’. AimTo investigate the nature of associations between impulsivity, aggression, and impulsive aggression, and suicidal ideation and behavior. MethodImpulsivity, aggression, impulsive aggression, and suicidal ideation and behavior, were assessed in 624 participants (aged 16 years and over) via an online survey. Participants were categorized as those with (1) no history of suicidal ideation or suicide attempts, (2) a history of suicidal ideation but not of suicide attempts, and (3) a history of suicidal ideation and suicide attempts. ResultsTwo pathways were associated with suicidality. First, all three constructs were associated with increased suicidality overall. Second, they were each associated with an increased likelihood to have a history of both suicidal ideation and action. LimitationsWe assessed psychological traits and further work is required to determine whether state-based measures yield consistent results. ConclusionImpulsivity, aggression, and impulsive aggression are each associated with increased suicidality overall and with the likelihood of having a history of both suicidal ideation and suicide attempts. The results will contribute to the development of suicide risk formulation and prevention by demonstrating how key psychological constructs contribute to the development of suicidality.

The concept of Evil in Psychiatry: Philosophy, neurobiology and clinical implications

IntroductionAlthough difficult to define, the concept of evil is widely used and implicitly influences psychiatric judgements and diagnosis. Most definitions of evil rely on classical philosophical concepts, but it remains controversial if evil is a concept by itself or rather a dysfunction on the ability to experience goodness. Also, it is unclear if there is a neurobiological basis for evil or if it is entirely dependent on socio-cultural beliefs.ObjectivesIn this work, we intend to systematize evidence on the philosophical definitions and neurobiological correlates of evil, and reflect on its implications in clinical psychiatry.MethodsLiterature review.ResultsThe concept of evil has been a theme of debate since the ancient Greek, where Plato argued that evil was a result of ignorance and Aristoteles saw morality as a guide for education and politics. Nietzsche claimed that evil was a dangerous concept that was created by the church, while Hannah Arendt underlined the banality of evil by highlighting “thoughtlessness” that frequently justify evil acts. From a neurobiological perspective, studies assessing individuals with neuro-psychiatric conditions associated with evil-related behavioral abnormalities have been suggesting a potential role of frontal and limbic structures, as well as of the serotonergic system. However, several of these studies assessed presumed correlates of evil, such as antisocial personality disorder or impulsive-aggressive behavior.ConclusionsDespite the polemic frontier between neurosciences and morality, a conceptual insight over the definition of evil is vital to guide comprehensiveness and clinical approach when dealing with deviant evil-like behaviors.DisclosureNo significant relationships.

Testing the Reliability and Validity of a Chinese Version of the Attitudes Towards School Violence Questionnaire with High School Students

We tested the validity and reliability of the Attitudes Towards School Violence Questionnaire with Chinese high school students. We translated the questionnaire into Chinese and performed exploratory factor analysis, confirmatory factor analysis, and test–retest and internal consistency reliability tests. As for the original questionnaire, the Chinese version of the Attitudes Towards School Violence Questionnaire comprises 28 items designed to measure four attitudes toward violence: that violence is a form of fun, a way to increase selfesteem, a way to solve problems, and perceived as legitimate. There were significant positive correlations among the students' attitudes toward school violence, and both their impulsive tendency and aggressive behavior. The results show that as the Chinese version of the Attitudes Towards School Violence Questionnaire had adequate psychometric properties, it can be used to assess the attitudes of Chinese high school students toward school violence.

Neuronal responses in social-emotional information processing in impulsive aggressive individuals.

How we perceive and interpret signals from others' behavior, known as social-emotional information processing (SEIP), is key when responding to social threat. Impulsively aggressive individuals, behaviorally, demonstrate impaired SEIP for encoding relevant social stimuli, attribution of intent of the other person in the interaction, and responding negatively to potentially threatening social situations. In this study, we sought to explore how neural processing differs between healthy controls (HC) and individuals with impulsive aggressive behavior (individuals with Intermittent Explosive Disorder, I-IED), during a validated SEIP paradigm. Forty-five adults (19 I-IED, 26 HC) participants underwent a validated SEIP tasks during an fMRI scan. The task utilized video clips depicting a socially ambiguous, but possibly aggressive (AGG), act by one person to another and control video clips in which where possibly aggressive act does not occur (CON). Behavioral anomalies in SEIP are also manifest in altered neural activation in distributed networks/brain regions in each phase of SEIP examined. Overall, neural responses during the SEIP paradigm were characterized as reduced discrimination of the AGG vs. CON videos for I-IEDs compared to HCs. These data suggest the presence of compromised neural circuits underlying impaired social cognition in individuals with IED and highlights potential neural targets of intervention for impaired social cognition in I-IED and other behavioral disorders as well.

Electrolytic lesions of the bilateral ventrolateral orbital cortex not only directly reduce depression-like behavior but also decreased desperate behavior induced by chronic unpredicted mild stress in rats

BackgroundPrevious studies have revealed that ventrolateral orbital cortex (VLO) may play an important role in the regulation of emotional behavior. However, it is not known what effect VLO damage will have on emotion regulation.ResultsData showed that damage of VLO increased the anxiety-like behavior in open field test and elevated plus maze, and decreased the depressive behavior in forced swimming test and learned helplessness test. Besides, the impulsive aggressive behaviors were also increased while the attack latency decreased after VLO lesion. What’s more, damage of VLO decreased depressive behaviors induced by chronic unpredicted mild stress in rats.ConclusionsThese results suggest that the integrity of VLO plays an important role in emotional regulation, and the damage of VLO may inhibit the development of depression-like behavior.

Cortical Correlates of Impulsive Aggressive Behavior in Pediatric Bipolar Disorder.

Background: Impulsive aggression represents a frequent characteristic of pediatric bipolar disorder (PBD). Cortical alterations associated with impulsive aggression and its multiple facets have not been investigated yet in youth with bipolar disorder.Aim: To investigate the relationship between cortical thickness and facets of impulsive aggression in youth with PBD.Materials and Methods: Twenty-three youth with PBD and 23 healthy controls (HC) were administered the aggression questionnaire (AQ) and underwent 3T magnetic resonance imaging scan. Cortical thickness was assessed with FreeSurfer. Canonical correlation analyses were used to investigate the relationship between AQ total and subscale scores and cortical thickness in youth with PBD.Results: Youth with PBD had increased scores in the subscales of AQ-anger and AQ-hostility and cortical thinning in in areas belonging to the affective network (AN), frontoparietal network (FPN) and cingulo-opercular network (CON), i.e., right rostral anterior cingulate, right caudal anterior cingulate, right lateral orbitofrontal, right medial orbitofrontal, left and right inferior parietal, left posterior cingulate, left and right supramarginal left lingual cortices. Greater thickness in these networks positively correlated with the AQ-hostility subscale and negatively correlated with AQ-anger subscale.Conclusions: The opposite patterns observed between areas belonging to AN, FPN, CON, and the two facets of IA, namely anger and hostility, corroborate clinical findings supporting the different nature of these two constructs.

The Dark Triad of Personality: Is Psychopathy a Good Predictor of Workplace Stress?

Background:Psychopathy as an antisocial characteristic of an individual is characterized by a lack of empathy, guilt, inability to control impulsive behavior, irresponsibility, irritability and aggressive behavior. Because of the traits that underlie this factor, we hypothesized that psychopaths would experience more stress in the work environment. Stress, in this article, is operationalized within Karasek’s model of stress which consider that contextual variables (excessive demands on work, lack of social support, and lack of control at work) are responsible for experiencing stress at the workplace. This kind of work context, according to our assumption, can affect psychopaths to have a weaker response to stressful situations.Objective:To determine the predictive power of psychopathy as a factor in the dark triad in order to explain the workplace stress.Methods:We conducted the study in one company on a sample of 235 respondents. Data were collected using the Sociodemographic Characteristics Questionnaire, the Dark Triad Questionnaire (SD27) and the Copenhagen Questionnaire for measuring cognitive, behavioral and somatic stress.Results:The mean age of the respondents was 39.04±10.27 years. Using standard regression analysis, we found that the dark triad model is the only significant one in explaining cognitive stress, and a significant predictor is psychopathy.Conclusion:In majority of previous studies, psychopathy has not been associated with stress, and the findings are important for future research that should shed light on the complex relationship between psychopathy and stress.

Platelet serotonin concentration and trait aggression in veterans with post-traumatic stress disorder: a preliminary study

Animal and human studies suggest that aggressive behavior may be modulated by brain serotonergic system. Serotonergic (5-HT) dysfunction is associated with post-traumatic stress disorder (PTSD), but also with increased aggression and impulsivity, hallmarks of PTSD. The aim of the study was to investigate the association of platelet 5-HT concentration and various types of aggression and impulsivity in veterans with PTSD. A group of 42 male combat-related PTSD subjects entered the study. Four different aggression facets were measured by the Buss and Perry's Aggression Questionnaire (BPAQ). Verbal and physical types of impulsive aggressive behavior were measured by the subscales of the Žužul's Aggressiveness Inventory A-87. Impulsivity was determined using Eysenck's IVE questionnaire. PTSD severity was evaluated by Watson’s PTSD questionnaire. Platelet serotonin concentration was determined spectrofluorimetrically. Confounding variables were: age, body mass, alcohol use, comorbid depression, and tobacco use. Platelet 5-HT concentration and PTSD severity were independently associated only with impulsive types of aggression, as higher platelet 5-HT concentration and more severe PTSD were related to more impulsive aggression. These results strongly recommend distinguishing between specific types of aggression facets, and advise the importance of theory-based concepts of aggression facets when evaluating the biological correlates of aggression.

Suicide Risk in a National VA Sample: Smoking and Behavior Regulation Versus Psychiatric Diagnosis

Suicide is associated with impaired behavior regulation. We examined relationships between suicide risk and smoking, other addictions, trauma-related disorders and impulsive-aggressive behavior, in a trans-diagnostic national community sample of over 350,000 Veterans.

Closing the gap: unmet needs of individuals with impulsive aggressive behavior observed in children and adolescents.

Impulsive aggressive (IA, or impulsive aggression) behavior describes an aggregate set of maladaptive, aggressive behaviors occurring across multiple neuropsychiatric disorders. IA is reactive, eruptive, sudden, and unplanned; it provides information about the severity, but not the nature, of its associated primary disorder. IA in children and adolescents is of serious clinical concern for patients, families, and physicians, given the detrimental impact pediatric IA can have on development. Currently, the ability to properly identify, monitor, and treat IA behavior across clinical populations is hindered by two major roadblocks: (1) the lack of an assessment tool designed for and sensitive to the set of behaviors comprising IA, and (2) the absence of a treatment indicated for IA symptomatology. In this review, we discuss the clinical gaps in the approach to monitoring and treating IA behavior, and highlight emerging solutions that may improve clinical outcomes in patients with IA.

Regulation of impulsive and aggressive behaviours by a novel lncRNA.

High impulsive and aggressive traits associate with poor behavioural self-control. Despite their importance in predicting behavioural negative outcomes including suicide, the molecular mechanisms underlying the expression of impulsive and aggressive traits remain poorly understood. Here, we identified and characterized a novel long noncoding RNA (lncRNA), acting as a regulator of the monoamine oxidase A (MAOA) gene in the brain, and named it MAOA-associated lncRNA (MAALIN). Our results show that in the brain of suicide completers, MAALIN is regulated by a combination of epigenetic mechanisms including DNA methylation and chromatin modifications. Elevated MAALIN in the dentate gyrus of impulsive-aggressive suicides was associated with lower MAOA expression. Viral overexpression of MAALIN in neuroprogenitor cells decreased MAOA expression while CRISPR-mediated knock out resulted in elevated MAOA expression. Using viral-mediated gene transfer, we confirmed that MAALIN in the hippocampus significantly decreases MAOA expression and exacerbates the expression of impulsive-aggressive behavioural traits in CD1 aggressive mice. Overall, our findings suggest that variations in DNA methylation mediate the differential expression of a novel lncRNA that acts on MAOA expression to regulate impulsive-aggressive behaviours.

Social desirability, deceptive reporting, and awareness of problematic aggression in intermittent explosive disorder compared with non-aggressive healthy and psychiatric controls

Individuals with DSM-5 Intermittent Explosive Disorder (IED) are often suspected of minimizing the nature of their recurrent, problematic, impulsive aggressive behavior due to the social undesirability of these behaviors. Our first study involved 400 study participants categorized as Healthy Controls (HC), Psychiatric Controls (PC) and as having IED and included the Crowne-Marlowe Social Desirability Scale (SDS), the Lie Scale from the Eysenck Personality Questionnaire-Revised (EPQ-R Lie), and the Readiness to Change (Anger) Questionnaire (RTC). IED study participants had lower SDS and lower EPQ-R Lie scores, while having higher RTC scores, compared with both HC and PC study participants. Thus, when studied in a clinical research setting, IED study participants do not provide socially desirable answers to questions and do not engaging in deceptive reporting; likely because they have recognized their need/interest in reducing their own impulsive aggressive behavior. The second study, part of a family study of 70 probands and their first-degree relatives revealed a very high positive (96.3%), but substantially lower negative (55.8%), predictive power for IED based on informant report. This suggests that, while interview of close informants can confirm the diagnosis of IED, informant interviews cannot rule out IED when such informants provide a negative report.