The Effect of Tonsillectomy and Adenoidectomy on Inattention and Impulsivity as Measured by the Test of Variables of Attention (TOVA) in Children with Obstructive Sleep Apnea Syndrome

OBJECTIVE: To evaluate children with obstructive sleep apnea syndrome (OSAS) for features of attention deficit disorder (ADD) using an objective test of inattention and impulsivity: Test of Variables of Attention (TOVA) and then to determine whether tonsillectomy and adenoidectomy (T+A) results in an improvement in TOVA scores.

STUDY DESIGN AND SETTING: This study was a prospective interventional comparative trial in a tertiary care children's hospital. Nineteen children ages 5 to 14 years with OSAS, and otherwise healthy, with a clinical indication for T+A. Preoperative and 2 months postoperative OSA-18, CBCL questionnaires, and TOVA scores were evaluated.

RESULTS: The preoperative TOVA scores were in the abnormal range in 12/19 (63%) of the children. The mean preoperative TOVA score was −2.9 (± 3.1). The mean postoperative TOVA score was −0.4 (±2.8). The improvement in the TOVA scores was significant ( P < 0.0001, t-test).

CONCLUSION: This preliminary data suggests that treatment of OSAS with T+A results in significant improvement in objective parameters of inattention and impulsivity.

SIGNIFICANCE: These findings may be important in understanding the impact of OSAS and therapeutic interventions on behavioral problems in children.

Serotonin at the nexus of impulsivity and cue reactivity in cocaine addiction

Cocaine abuse and addiction remain great challenges on the public health agendas in the U.S. and the world. Increasingly sophisticated perspectives on addiction to cocaine and other drugs of abuse have evolved with concerted research efforts over the last 30 years. Relapse remains a particularly powerful clinical problem as, even upon termination of drug use and initiation of abstinence, the recidivism rates can be very high. The cycling course of cocaine intake, abstinence and relapse is tied to a multitude of behavioral and cognitive processes including impulsivity (a predisposition toward rapid unplanned reactions to stimuli without regard to the negative consequences), and cocaine cue reactivity (responsivity to cocaine-associated stimuli) cited as two key phenotypes that contribute to relapse vulnerability even years into recovery. Preclinical studies suggest that serotonin (5-hydroxytryptamine; 5-HT) neurotransmission in key neural circuits may contribute to these interlocked phenotypes well as the altered neurobiological states evoked by cocaine that precipitate relapse events. As such, 5-HT is an important target in the quest to understand the neurobiology of relapse-predictive phenotypes, to successfully treat this complex disorder and improve diagnostic and prognostic capabilities. This review emphasizes the role of 5-HT and its receptor proteins in key addiction phenotypes and the implications of current findings to the future of therapeutics in addiction. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'.

Prevalence of neurobehavioral, social, and emotional dysfunction in patients treated for childhood craniopharyngioma: a systematic literature review

Background

Craniopharyngiomas (CP) are locally invasive and frequently recurring neoplasms often resulting in neurological and endocrinological dysfunction in children. In addition, social-behavioral impairment is commonly reported following treatment for childhood CP, yet remains to be fully understood. The authors aimed to further characterize the prevalence of neurobehavioral, social, and emotional dysfunction in survivors of childhood craniopharyngiomas.

Materials and Methods

A systematic literature review was conducted in PubMed to identify studies formally assessing neurobehavioral, social, and emotional outcomes in patients treated for CP prior to 18 years of age. Studies published between the years 1990-2012 that reported the primary outcome (prevalence of neurobehavioral, social, emotional/affective dysfunction, and/or impaired quality of life (QoL)) in ≥10 patients were included.

Results

Of the 471 studies screened, 11 met inclusion criteria. Overall neurobehavioral dysfunction was reported in 51 of 90 patients (57%) with available data. Social impairment (i.e. withdrawal, internalizing behavior) was reported in 91 of 222 cases (41%). School dysfunction was reported in 48 of 136 patients (35%). Emotional/affective dysfunction was reported in 58 of 146 patients (40%), primarily consisting of depressive symptoms. Health related quality of life was affected in 49 of 95 patients (52%). Common descriptors of behavior in affected children included irritability, impulsivity, aggressiveness, and emotional outbursts.

Conclusions

Neurobehavioral, social, and emotional impairment is highly prevalent in survivors of childhood craniopharyngioma, and often affects quality of life. Thorough neurobehavioral/emotional screening and appropriate counseling is recommended in this population. Additional research is warranted to identify risk factors and treatment strategies for these disorders.

Biological and rearing mother influences on child ADHD symptoms: revisiting the developmental interface between nature and nurture

BACKGROUND

Families of children with attention deficit hyperactivity disorder (ADHD) report more negative family relationships than families of children without ADHD. Questions remain as to the role of genetic factors underlying associations between family relationships and children's ADHD symptoms, and the role of children's ADHD symptoms as an evocative influence on the quality of relationships experienced within such families. Utilizing the attributes of two genetically sensitive research designs, the present study examined associations between biologically related and nonbiologically related maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. The combined attributes of the study designs permit assessment of associations while controlling for passive genotype-environment correlation and directly examining evocative genotype-environment correlation (rGE); two relatively under examined confounds of past research in this area.

METHODS

A cross-sectional adoption-at-conception design (Cardiff IVF Study; C-IVF) and a longitudinal adoption-at-birth design (Early Growth and Development Study; EGDS) were used. The C-IVF sample included 160 mothers and children (age 5-8 years). The EGDS sample included 320 linked sets of adopted children (age 6 years), adoptive-, and biologically related mothers. Questionnaires were used to assess maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. A cross-rater approach was used across measures of maternal behavior (mother reports) and child ADHD symptoms (father reports).

RESULTS

Significant associations were revealed between rearing mother ADHD symptoms, hostile parenting behavior, and child ADHD symptoms in both samples. Because both samples consisted of genetically unrelated mothers and children, passive rGE was removed as a possible explanatory factor underlying these associations. Further, path analysis revealed evidence for evocative rGE processes in the longitudinal adoption-at-birth study (EGDS) from biologically related maternal ADHD symptoms to biologically unrelated maternal hostile parenting through early disrupted child behavior (impulsivity/activation), with maternal hostile parenting and disrupted child behavior associated with later child ADHD symptoms, controlling for concurrent adoptive mother ADHD symptoms.

CONCLUSIONS

Results highlight the importance of genetically influenced child ADHD-related temperamental attributes on genetically unrelated maternal hostility that in turn links to later child ADHD symptoms. Implications for intervention programs focusing on early family processes and the precursors of child ADHD symptoms are discussed.

Genetic and environmental risk factors in males for self-report externalizing traits in mid-adolescence and criminal behavior through young adulthood

BACKGROUND

Externalizing traits or behaviors are typically assessed by self-report scales or criminal records. Few genetically informative studies have used both methods to determine whether they assess the same genetic or environmental risk factors.

METHOD

We examined 442 male Swedish twin pairs with self-reported externalizing behaviors at age 16–17 years [externalizing traits (EXT), self-reported delinquency (SRD), impulsivity (IMP), grandiosity (GRD) and callousness (CLS)] and criminal behavior (CB) from the National Suspect Registry from age 13 to 25 years. Multivariate structural equation modeling was conducted with Mx.

RESULTS

The best-fit model contained one genetic, one shared environmental and two non-shared environmental common factors, and variable specific genetic and non-shared environmental factors. The risk for CB was influenced substantially by both genetic (a2=0.48) and familial–environmental factors (c2=0.22). About one-third of the genetic risk for CB but all of the shared environmental risk was indexed by the self-report measures. The degree to which the individual measures reflected genetic versus familial–environmental risks for CB varied widely. GRD and CLS were correlated with CB mainly through common genetic risk factors. SRD and CB covaried largely because of shared familial–environmental factors. For EXT and IMP, observed correlations with CB resulted in about equal parts from shared genetic and shared familial–environmental factors.

CONCLUSIONS

In adolescence, measures of grandiose and callous temperament best tap the genetic liability to CB.Measures of antisocial behaviors better index familial–environmental risks for CB. A substantial proportion of the genetic risk to CB was not well reflected in any of the self-report measures.

Test-retest reliability and gender differences in the sexual discounting task among cocaine-dependent individuals

The Sexual Discounting Task uses the delay discounting framework to examine sexual HIV risk behavior. Previous research showed task performance to be significantly correlated with self-reported HIV risk behavior in cocaine dependence. Test-retest reliability and gender differences had remained unexamined. The present study examined the test-retest reliability of the Sexual Discounting Task. Cocaine-dependent individuals (18 men, 13 women) completed the task in two laboratory visits ∼7 days apart. Participants selected photographs of individuals with whom they were willing to have casual sex. Among these, participants identified the individual most (and least) likely to have a sexually transmitted infection (STI), and the individual with whom he or she most (and least) wanted to have sex. In reference to these individuals, participants rated their likelihood of having unprotected sex versus waiting to have sex with a condom, at various delays. A money delay discounting task was also completed at the first visit. Significant differences in discounting among partner conditions were shown. Differential stability was demonstrated by significant, positive correlations between test and retest for all four partner conditions. Absolute stability was demonstrated by statistical equivalence tests between test and retest, and also supported by a lack of significant differences between test and retest. Men generally discounted significantly more than women for sexual outcomes but not money. Results suggest the Sexual Discounting Task to be a reliable measure in cocaine-dependent individuals, which supports its use as a repeated measure in clinical research, for example, studies examining acute drug effects on sexual risk and the effects of addiction treatment and HIV prevention interventions on sexual risk.

Prosocial effects of oxytocin in two mouse models of autism spectrum disorders

Clinical evidence suggests that oxytocin treatment improves social deficits and repetitive behavior in autism spectrum disorders (ASDs). However, the neuropeptide has a short plasma half-life and poor ability to penetrate the blood-brain barrier. In order to facilitate the development of more bioavailable oxytocinergic compounds as therapeutics to treat core ASD symptoms, small animal models must be validated for preclinical screens. This study examined the preclinical utility of two inbred mouse strains, BALB/cByJ and C58/J, that exhibit phenotypes relevant to core ASD symptoms. Mice from both strains were intraperitoneally administered oxytocin, using either acute or sub-chronic regimens. Acute oxytocin did not increase sociability in BALB/cByJ; however, sub-chronic oxytocin had significant prosocial effects in both BALB/cByJ and C58/J. Increased sociability was observed 24 h following the final oxytocin dose in BALB/cByJ, while prosocial effects of oxytocin emerged 1-2 weeks post-treatment in C58/J. Furthermore, acute oxytocin decreased motor stereotypy in C58/J and did not induce hypoactivity or anxiolytic-like effects in an open field test. This study demonstrates that oxytocin administration can attenuate social deficits and repetitive behavior in mouse models of ASD, dependent on dose regimen and genotype. These findings provide validation of the BALB/cByJ and C58/J models as useful platforms for screening novel drugs for intervention in ASDs and for elucidating the mechanisms contributing to the prosocial effects of oxytocin.

Poor attention rather than hyperactivity/impulsivity predicts academic achievement in very preterm and full-term adolescents

BACKGROUND

Very preterm (VP) children are at particular risk for attention deficit/hyperactivity disorder (ADHD) of the inattentive subtype. It is unknown whether the neurodevelopmental pathways to academic underachievement are the same as in the general population. This study investigated whether middle childhood attention or hyperactivity/impulsivity problems are better predictors of VP adolescents' academic achievement.

METHOD

In a geographically defined prospective whole-population sample of VP (<32 weeks gestation) and/or very low birth weight (<1500 g birth weight) (VLBW/VP; n = 281) and full-term control children (n = 286) in South Germany, ADHD subtypes were assessed at 6 years 3 months and 8 years 5 months using multiple data sources. Academic achievement was assessed at 13 years of age.

RESULTS

Compared with full-term controls, VLBW/VP children were at higher risk for ADHD inattentive subtype [6 years 3 months: odds ratio (OR) 2.8, p < 0.001; 8 years 5 months: OR 1.7, p = 0.020] but not for ADHD hyperactive-impulsive subtype (6 years 3 months: OR 1.4, p = 0.396; 8 years 5 months: OR 0.9, p = 0.820). Childhood attention measures predicted academic achievement in VLBW/VP and also full-term adolescents, whereas hyperactive/impulsive behaviour did not.

CONCLUSIONS

Attention is an important prerequisite for learning and predicts long-term academic underachievement. As ADHD inattentive subtype and cognitive impairments are frequent in VLBW/VP children, their study may help to identify the neurofunctional pathways from early brain development and dysfunction to attention problems and academic underachievement.

Theoretical frameworks and mechanistic aspects of alcohol addiction: alcohol addiction as a reward deficit disorder

Alcoholism can be defined by a compulsion to seek and take drug, loss of control in limiting intake, and the emergence of a negative emotional state when access to the drug is prevented. Alcoholism impacts multiple motivational mechanisms and can be conceptualized as a disorder that includes a progression from impulsivity (positive reinforcement) to compulsivity (negative reinforcement). The compulsive drug seeking associated with alcoholism can be derived from multiple neuroadaptations, but the thesis argued here is that a key component involves the construct of negative reinforcement. Negative reinforcement is defined as drug taking that alleviates a negative emotional state. The negative emotional state that drives such negative reinforcement is hypothesized to derive from dysregulation of specific neurochemical elements involved in reward and stress within the basal forebrain structures involving the ventral striatum and extended amygdala, respectively. Specific neurochemical elements in these structures include not only decreases in reward neurotransmission, such as decreased dopamine and γ-aminobutyric acid function in the ventral striatum, but also recruitment of brain stress systems, such as corticotropin-releasing factor (CRF), in the extended amygdala. Acute withdrawal from chronic alcohol, sufficient to produce dependence, increases reward thresholds, increases anxiety-like responses, decreases dopamine system function, and increases extracellular levels of CRF in the central nucleus of the amygdala. CRF receptor antagonists also block excessive drug intake produced by dependence. A brain stress response system is hypothesized to be activated by acute excessive drug intake, to be sensitized during repeated withdrawal, to persist into protracted abstinence, and to contribute to the compulsivity of alcoholism. Other components of brain stress systems in the extended amygdala that interact with CRF and that may contribute to the negative motivational state of withdrawal include norepinephrine, dynorphin, and neuropeptide Y. The combination of loss of reward function and recruitment of brain stress systems provides a powerful neurochemical basis for a negative emotional state that is responsible for the negative reinforcement driving, at least partially, the compulsivity of alcoholism.

Genetic and environmental influences on adult attention deficit hyperactivity disorder symptoms: a large Swedish population-based study of twins

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) frequently persists into adulthood. Family and twin studies delineate a disorder with strong genetic influences among children and adolescents based on parent- and teacher-reported data but little is known about the genetic and environmental contribution to DSM-IV ADHD symptoms in adulthood. We therefore aimed to investigate the impact of genetic and environmental influences on the inattentive and hyperactive-impulsive symptoms of ADHD in adults.

METHOD

Twin methods were applied to self-reported assessments of ADHD symptoms from a large population-based Swedish twin study that included data from 15 198 Swedish male and female twins aged 20 to 46 years.

RESULTS

The broad heritability [i.e., A + D, where A is an additive genetic factor and D (dominance) a non-additive genetic factor] was 37% (A = 11%, D = 26%) for inattention and 38% (A = 18%, D = 20%) for hyperactivity-impulsivity. The results also indicate that 52% of the phenotypic correlation between inattention and hyperactivity-impulsivity (r = 0.43) was explained by genetic influences whereas the remaining part of the covariance was explained by non-shared environmental influences. These results were replicated across age strata.

CONCLUSIONS

Our findings of moderate broad heritability estimates are consistent with previous literature on self-rated ADHD symptoms in older children, adolescents and adults and retrospective reports of self-rated childhood ADHD by adults but differ from studies of younger children with informant ratings. Future research needs to clarify whether our data indicate a true decrease in the heritability of ADHD in adults compared to children, or whether this relates to the use of self-ratings in contrast to informant data.

[Repetitive impulse-associated behavioral disorders in Parkinson's disease]

Parkinson's disease (PD) is associated with a number of behavioral disorders which may cause considerable social, professional or financial problems. Impulse control disorders (ICDs), such as pathological gambling, binge eating, compulsive shopping and hypersexuality occur in approximately 13-14% of PD patients. Further behavioral disorders are the dopamine dysregulation syndrome (DDS), a substance dependence characterized by craving for dopaminergic substances and punding (prolonged repetitive activities which are not goal-oriented).Treatment-related risk factors are dopamine agonists for ICDs and a high total dopaminergic dose for DDS and punding. Shared risk factors are young age at onset, impulsive personality traits, depression and possibly dyskinesia. At the neuronal level these behavioral disorders seem to be associated with changes in the reward system and dysfunction of the orbitofrontal cortex. The evidence level for management strategies is at present insufficient. For ICDs current clinical practice consists of discontinuation or reduction of dopamine agonists.

Orbitofrontal cortex and impulsivity in borderline personality disorder: an MRI study of baseline brain perfusion

Behavioral and neuroimaging studies in patients with borderline personality disorder (BPD) have associated orbitofrontal cortex (OFC) dysfunction with distinct symptom clusters such as impulsivity. It is unclear, however, whether abnormal patterns of OFC activity are also present during resting-state conditions and whether OFC dysfunction is specifically associated with impulsivity in BPD. This study tested the hypothesis that BPD patients would exhibit changes of OFC baseline perfusion and explored the relationship between regional cerebral blood flow and distinct BPD symptom clusters, such as impulsivity, dissociation tension and depressive symptoms. Using continuous arterial spin labeling magnetic resonance imaging at 3 Tesla, we investigated 16 women with BPD according to DSM-IV criteria and 16 healthy female control participants during resting-state conditions. Between-group comparisons were conducted using an analysis of variance (p < 0.05 cluster corrected). Compared to controls, BPD patients exhibited decreased blood flow in the medial OFC, whereas increased blood flow was found in the left and right lateral OFC. Correlation analyses revealed a positive relationship between medial and lateral orbitofrontal blood flow and impulsivity scores, whereas measures of dissociation tension and depression did not exhibit a significant correlation with OFC perfusion. These data suggest that dysfunction of medial and lateral regions of the OFC could specifically mediate symptoms of impulsivity in BPD.

Affect regulation and psychopathology in women with borderline personality disorder

INTRODUCTION

Dysfunction in affect regulation is a prominent feature that grossly impairs behavioural and interpersonal domains of experience and underlies a great deal of the psychopathology in borderline personality disorder (BPD). However, no study has yet been published that evaluates the psychometric properties of the translated Danish version of self-report measures sensitive to the different aspects and dimensions of dysfunction in affect regulation prevalent in BPD.

MATERIAL AND METHODS

This study comprised a group of women diagnosed with BPD (n = 29) and a comparison group of healthy subjects (n = 29) who reported psychopathology and levels of affective instability, aggression, impulsivity and alexithymia by self-report measures.

RESULTS

Our results demonstrated that women with BPD have significant psychopathology and report significantly higher levels of dysfunction in separate components of affect regulation by self-report measures than the comparison group of healthy subjects. Our results also provided partial support for the psychometric appropriateness and clinical relevance of the translated Danish version of affect regulation measures.

CONCLUSION

The normative reference range indicated by our results makes the measures useful as a practical assessment tool.

FUNDING

not relevant.

TRIAL REGISTRATION

not relevant.

Trait-based affective processes in alcohol-involved "risk behaviors"

This study tested a theoretical model of alcohol use, markers of extreme intoxication, and risk behavior as a function of trait affect, distress tolerance, and affect-based behavior dysregulation. Positive affective pathways to risk behavior were primarily expected to be indirect via high levels of alcohol use, while negative affect paths were expected to be more directly associated with engagement in risk behavior. In addition, we expected trait affectivity and distress tolerance would primarily exhibit relationships with alcohol use and problems through behavioral dysregulation occurring during extreme affective states. To evaluate these hypotheses, we tested a SEM with three alcohol-related outcomes: "Typical" alcohol use, "blackout" drinking, and risk behavior. High trait negative affect and low tolerance for affective distress contribute to difficulty controlling behavior when negatively aroused and this is directly associated with increased risk behavior when drinking. In contrast, associations between positive urgency and risk behaviors are indirect via increased alcohol consumption. Positive affectivity exhibited both inverse and positive effects in the model, with the net effect on alcohol outcomes being insignificant. These findings contribute important information about the distinct pathways between affect, alcohol use, and alcohol-involved risk behavior among college students.

Temporal discounting in heroin-dependent patients: no sign effect, weaker magnitude effect, and the relationship with inhibitory control

Impulsive behavior in heroin-dependent individuals and matched smokers was studied within the framework of temporal discounting. Two well-known effects were examined: the sign and magnitude effects (Kirby, 1997). The study also investigated the relationship between cognitive impulsivity and inhibitory control as measured by a Go/No-go task. Fifty-six heroin-dependent patients in the postmethadone treatment stage and an equal number of matched daily smokers participated in the study. The heroin-dependent patients showed higher discount rates in both gain and loss conditions. They also showed no sign effect by demonstrating similar discount rates in gains and losses. Heroin-dependent patients also exhibited a magnitude effect, which was weaker than that observed in smokers. Differential relationships between impulsivity and inhibitory control were found in the two groups. For smokers, decision-making and inhibitory control behaviors pertained to different psychological processes, whereas for heroin-dependent patients, the two behaviors were partially related. Finally, a significant correlation between length of heroin use and temporal discounting with small magnitude was found. The present study advances our understanding of the specific behavioral impulsive patterns in heroin-dependent individuals.

BMI predicts emotion-driven impulsivity and cognitive inflexibility in adolescents with excess weight

Adolescent obesity is increasingly viewed as a brain-related dysfunction, whereby reward-driven urges for pleasurable foods "hijack" response selection systems, such that behavioral control progressively shifts from impulsivity to compulsivity. In this study, we aimed to examine the link between personality factors (sensitivity to reward (SR) and punishment (SP), BMI, and outcome measures of impulsivity vs. flexibility in--otherwise healthy--excessive weight adolescents. Sixty-three adolescents (aged 12-17) classified as obese (n = 26), overweight (n = 16), or normal weight (n = 21) participated in the study. We used psychometric assessments of the SR and SP motivational systems, impulsivity (using the UPPS-P scale), and neurocognitive measures with discriminant validity to dissociate inhibition vs. flexibility deficits (using the process-approach version of the Stroop test). We tested the relative contribution of age, SR/SP, and BMI on estimates of impulsivity and inhibition vs. switching performance using multistep hierarchical regression models. BMI significantly predicted elevations in emotion-driven impulsivity (positive and negative urgency) and inferior flexibility performance in adolescents with excess weight--exceeding the predictive capacity of SR and SP. SR was the main predictor of elevations in sensation seeking and lack of premeditation. These findings demonstrate that increases in BMI are specifically associated with elevations in emotion-driven impulsivity and cognitive inflexibility, supporting a dimensional path in which adolescents with excess weight increase their proneness to overindulge when under strong affective states, and their difficulties to switch or reverse habitual behavioral patterns.

Decision making, impulsivity, and addictions: do Parkinson's disease patients jump to conclusions?

Links between impulsive-compulsive behaviors (ICBs) in treated Parkinson's disease (PD), behavioral addictions, and substance abuse have been postulated, but no direct comparisons have been carried out so far. We directly compared patients with PD with and without ICBs with illicit drug abusers, pathological gamblers, and age-matched healthy controls using the beads task, a test of reflection impulsivity, and a working memory task. We found that all patients with PD made more impulsive and irrational choices than the control group. PD patients who had an ICB showed similar behavior to illicit substance abusers, whereas patients without ICBs more closely resembled pathological gamblers. In contrast, we found no difference in working memory performance within the PD groups. However, PD patients without ICBs remembered distractors significantly less than all other patients during working memory tests. We were able to correctly classify 96% of the PD patients with respect to whether or not they had an ICB by analyzing three trials of the 80/20 loss condition of the beads task with a negative prediction value of 92.3%, and we propose that this task may prove to be a powerful screening tool to detect an ICB in PD. Our results also suggest that intact cortical processing and less distractibility in PD patients without ICBs may protect them from developing behavioral addictions.

The latent structure of attention deficit/hyperactivity disorder in an adult sample

The vast majority of studies that have examined the latent structure of attention deficit/hyperactivity disorder (ADHD) in children and adolescents have concluded that ADHD has a dimensional latent structure. In other words, ADHD symptomatology exists along a continuum and there is no natural boundary or qualitative distinction (i.e., taxon) separating youth with ADHD from those with subclinical inattention or hyperactivity/impulsivity problems. Although adult ADHD appears to be less prevalent than ADHD in youth (which could suggest a more severe adult ADHD taxon), researchers have yet to examine the latent structure of ADHD in adults. The present study used a sample (N = 600) of adults who completed a self-report measure of ADHD symptoms. The taxometric analyses revealed a dimensional latent structure for inattention, hyperactivity/impulsivity, and ADHD. These findings are consistent with previous taxometric studies that examined ADHD in children and adolescents, and with contemporary polygenic and multifactorial models of ADHD.

[Impact of treatment with acetylcholinesterase inhibitors, valproic acid and antipsychotics on aggressive behaviour in Alzheimer's type dementia]

Aggressive and impulsive behaviour are common in Alzheimer's dementia. Therapy of these disorders is an important but difficult practical question.

AIM

The purpose of this study was to determine the effect of pharmacological treatment of aggressive behaviour, while taking into account the dynamics of disease progression during observation. In the assessment of treatment acetylcholinesterase inhibitors (IAChE), valproic acid (VA), and antipsychotics were considered.

METHOD

The study was based on a two-year naturalistic observation of nursing homes' residents with a diagnosis of possible Alzheimer's disease (NINCDS/ADRDA criteria) in its mild and moderate stage (at least 12 points in MMSE). Aggressive behaviour was measured by Cohen-Mansfield Agitation Inventory (CMAI), and the severity of dementia by ADAS--Cog. Examination was performed twice: at baseline (0) and after two years of observation (2). All treatment administered during this time has been taken into account. 71 people diagnosed with Alzheimer's disease were enrolled to the observation. The average age was 77.10 (SD = 8.39), the level of cognitive impairment by ADAS--Cog = 20.40 points (SD = 5.24). The second examination was conducted in 43 individuals.

RESULTS

In the group treated with IAChE there was a lesser increase of aggressive and impulsive behaviour in comparison to other persons. The differences between the examination (2) and (0) for the CMAI global scale were, respectively, 2.76 and 9.09 points. Similar results were obtained for subjects treated with VA (1.0 and 8.65). Antipsychotic drugs revealed a similar correlation (3.0 and 8.65), but this has not proven statistically relevant, while in the group treated with antipsychotics a significantly greater progression of dementia was observed.

CONCLUSION

Acetylcholinesterase inhibitors may have beneficial effects on aggressive behaviour in the course of Alzheimer's Disease, similar to that seen with the use of valproic acid and antipsychotics.

[Impulsivity and compulsivity in cocaine dependent individuals]

A recent theoretical approach describes addiction as a dynamic behavioural change process on the impulsivity-compulsivity axis. However, on the basis of current evidence, it is still difficult to establish a selective association between the course of addiction and individual transition along this axis. The aim of this study is to categorize each of the individuals in a sample of cocaine-dependent patients (CDI) as mainly impulsive or mainly compulsive, on the basis of their performance in neuropsychological inhibition and perseveration tests, and to test the association between the assigned category and their scores in trait impulsivity, and severity of cocaine addiction (measured by means of self-report assessment tools). A total of 42 CDI and 65 healthy control individuals (HCI) were assessed using the UPPS-P Scale (to explore trait impulsivity), the Stroop and Go/No Go (to assess response inhibition), and Revised-Strategy Application and Probabilistic Reversal tests (to assess response perseveration). Forty-five per cent of the CDIs were classified as compulsive, and this subgroup scored significantly higher than the impulsive group on the UPPS-P dimensions of lack of perseverance and lack of premeditation. A substantial proportion of CDIs can be classified as compulsive. No differences between compulsive and impulsive CDIs were found with regard to severity of exposure to cocaine; however, patients classified as compulsive by means of neuropsychological tasks are less perseverative in the pursuit of long-term objectives and more prone to make under-meditated decisions, as shown by trait impulsivity assessment questionnaires.

Impulsivity and Parkinson's disease: more than just disinhibition

In the last few years it has become clear that impulsivity is a complex behaviour composed of different domains and dependent on different neural networks. The proposed pathogenetic mechanisms for the emergence of impulsivity disorders in Parkinson's Disease (PD) can be broadly separated into three potentially interacting processes: the contribution of premorbid susceptibility to impulsivity, the contribution of the disease itself to the behaviour and the potential contribution of therapeutic agents. Growing evidence suggests that dopamine and the subthalamic nucleus are playing a certain role in the pathophysiology of different aspects of impulsivity. In this review, we summarise the main concepts defining various components of impulsivity both in healthy subjects and patients affected by PD.

Using a Virtual Classroom environment to describe the attention deficits profile of children with Neurofibromatosis type 1

The objectives of this study were to describe the nature of the attention deficits in children with Neurofibromatosis type 1 (NF1) in comparison with typically developing (TD) children, using the Virtual Classroom (VC), and to assess the utility of this instrument for detecting attention deficits. Twenty-nine NF1 children and 25 age-and gender-matched controls, aged 8-16, were assessed in a VC. Parents' ratings on the Conners' Parent Rating Scales-Revised: Long (CPRS-R:L) questionnaire were used to screen for Attention Deficit-Hyperactivity Disorder (ADHD). Significant differences were found between the NF1 and the control groups on the number of targets correctly identified (omission errors) and the number of commissions (commission errors) in the VC, with poorer performance by the NF1 children (p < 0.005). Significant correlations were obtained between the number of targets correctly identified, the number of commission errors, and the reaction time. Significant correlations were also found between the total correct hits and the cognitive problems/inattention scale, as well as two other indexes of the CPRS-R:L: the DSM-IV Symptoms Subscale and the ADHD Index. The VC results support the hypothesis that NF1 is marked by inattention and impulsivity and that participants with NF1 are more inattentive (omission errors) and impulsive (commission errors) than normal controls. The VC appears to be a sensitive and ecologically valid assessment tool for use in the diagnosis of attention deficits among children with NF1.

Individuals family history positive for alcoholism show functional magnetic resonance imaging differences in reward sensitivity that are related to impulsivity factors

BACKGROUND

Substance-abusing individuals tend to display abnormal reward processing and a vulnerability to being impulsive. Detoxified alcoholics show differences in regional brain activation during a monetary incentive delay task. However, there is limited information on whether this uncharacteristic behavior represents a biological predisposition toward alcohol abuse, a consequence of chronic alcohol use, or both.

METHODS

We investigated proposed neural correlates of substance disorder risk by examining reward system activity during a monetary incentive delay task with separate reward prospect, reward anticipation, and reward outcome phases in 30 individuals with and 19 without family histories of alcoholism. All subjects were healthy, lacked DSM-IV past or current alcohol or substance abuse histories, and were free of illegal substances as verified by a urine toxicology screening at the time of scanning. Additionally, we explored specific correlations between task-related nucleus accumbens (NAcc) activation and distinct factor analysis-derived domains of behavioral impulsivity.

RESULTS

During reward anticipation, functional magnetic resonance imaging data confirmed blunted NAcc activation in family history positive subjects. In addition, we found atypical activation in additional reward-associated brain regions during additional task phases. We further found a significant negative correlation between NAcc activation during reward anticipation and an impulsivity construct.

CONCLUSIONS

Overall, results demonstrate that sensitivity of the reward circuit, including NAcc, is functionally different in alcoholism family history positive individuals in multiple regards.

[Borderline personality disorder and bipolar II disorder--similarities and differences]

Since both borderline personality disorder (BPD) and bipolar II disorder (BP-II) are common psychiatric diagnoses due to their co-morbidity and similar characteristics, some researchers suggested they coexist along a spectrum of cyclical affective disorders. As part of the ongoing debate regarding these central diagnoses, a few studies were recently conducted. The results showed that patients with BPD reported higher Levels of impulsiveness and hostility across Axis I diagnostic groups. Furthermore, refining the impulsivity scale revealed different types of impulsivity in the two disorders. This should be carefully considered as impulsivity is known to predict suicidal behavior in both disorders. Subjective reported depression differed across groups, with BPD patients reporting higher Levels of cognitive and anxiety-related symptoms, supporting the notion that BPD patients show increased sensitivity to negative emotional states. Thus, providing further evidence that BP-II and BPD are distinct diagnostic entities. On the other hand, recent studies didn't attain statistically significant differences between bipolar disorder and BPD, although BPD patients displayed higher scores than unipolar patients in mood and cognition depressive subdomains. Further research is still needed to clarify this diagnostic and clinical question.

Facial self-induced paraffinoma in an elderly woman

A 72-year-old Caucasian woman without remarkable medical history presented with an asymptomatic bilateral periocular swelling, which had been present for 2 months. Physical examination showed symmetric indurated periocular erythematous plaques (Figure 1). Biopsy of a skin lesion revealed aggregates of vacuoles of different sizes (Figure 2) surrounded by a prominent inflammatory infiltrate constituted by macrophages, lymphocytes, neutrophils, and granulomatous foreign body reaction throughout the reticular dermis and hypodermis. These histological findings were consistent with the injection of an oily foreign substance. The patient denied the self-induced nature of the lesions, so she was referred for psychiatric evaluation and admitted having self-injected mineral oil as an impulsive attempt to get attention from her family. She was diagnosed with borderline personality disorder (BPD) and started treatment with oral fluoxetine, showing a rapid decrease of impulsive behavior and anxiety from the second week with a mean dose of 80 mg/d.

Discounting of delayed rewards and executive dysfunction in individuals infected with hepatitis C

OBJECTIVE

Determine whether adults with hepatitis C (HCV), regardless of substance use disorder, are more likely to discount delayed rewards than adults without hepatitis C, and explore the relationship between delay discounting and neuropsychological functioning.

METHODS

Procedures included clinical interviews, neuropsychological testing, and a delay discounting task.

RESULTS

Regardless of substance abuse history, adults with hepatitis C were significantly more likely to choose smaller immediate rewards over larger delayed rewards. Delay discounting correlated with performance on executive functioning tasks.

CONCLUSIONS

Increased discounting is associated with broad executive dysfunction, suggesting that HCV-associated executive dysfunction may lead to altered decision-making style.

Altruistic punishment in patients with Parkinson's disease with and without impulsive behaviour

Punishing violators of social norms when there is personal cost is known as altruistic punishment. We tested patients with Parkinson's disease (PD) with and without impulsive-compulsive behaviours (ICBs) and matched control subjects, on and off their regular dopamine replacement therapy on a task, in which the patients decided whether or not to invest a sum of money with a trustee. The sum was then quadrupled and the trustee could decide whether or not to return a portion of the investment. Participants could punish the trustee after they were informed of the trustee's decision. We found that PD patients without ICBs on or off medication punished more often than controls, whereas PD patients with ICBs punished more than controls on medication, but similar to controls off medication. These results suggest a role for dopamine in altruistic punishment decisions in PD patients with impulsive compulsive behaviour.

Insular cortex volume and impulsivity in teenagers with first-presentation borderline personality disorder

Fronto-limbic neural dysfunction has been implicated in the emotional dysregulation and impulsivity seen in borderline personality disorder (BPD). However, it remains unclear whether affected individuals exhibit morphologic changes of the insular cortex, a fronto-limbic integration cortex engaged in emotional regulation and impulse control. This magnetic resonance imaging study examined the insular cortex volume and its relationship to clinical characteristics in a first-presentation teenage BPD sample. No significant difference was found in the insular volume between 20 BPD participants (5 males) and 20 healthy control participants (5 males). There was no association between the insular volume and parasuicidal episodes, trauma exposure, or comorbid Axis I disorders, but the BPD participants with violent episodes during the previous 6 months had a smaller insular volume bilaterally compared with those without such episodes. Furthermore, right anterior insular volume in the BPD participants was negatively correlated with impulsivity score. These preliminary findings suggest that insular cortex volume does not significantly differ in early BPD, but that there might be a relationship with violent and impulsive behavior that is often seen in the disorder. Further studies are needed to clarify whether the potential relationship between the insular cortex volume and impulsivity is specific to BPD.

Impulsivity as a behavioral measure of withdrawal of orally delivered PCP and nondrug rewards in male and female monkeys

BACKGROUND

Withdrawal of phencyclidine (PCP), ethanol (ETOH), and other drugs reduces operant responding maintained by food.

OBJECTIVES

Experiment 1 examined the effects of withdrawing daily short access (2 h) to drug on impulsivity for saccharin (SACC) using a delay discounting task and comparing male and female rhesus monkeys. Experiment 2 examined the effects of withdrawing a nondrug substance (e.g., food or SACC) on impulsivity for PCP.

MATERIALS AND METHODS

In experiment 1, either PCP or ETOH was available daily with water for 2 h under a fixed ratio 16 (FR 16) or FR 8 schedule, respectively. In a second component, SACC was available for 45 min under a delay discounting schedule. Next, water was substituted, and drug access was then restored. In experiment 2, PCP was available under a delay discounting schedule during food satiation or restriction or during concurrent SACC vs water access.

RESULTS

In experiment 1, withdrawal of 0.5 mg/ml PCP increased impulsivity for SACC, but not SACC intake, in males and females. During 16% ETOH access, impulsivity for SACC was elevated compared to baseline water access, and it returned to baseline levels during ETOH withdrawal. In experiment 2, food restriction resulted in increased PCP intake in males and females and increases in impulsivity for PCP that were greater in males than in females. SACC withdrawal had no effect on impulsivity for PCP or PCP intake.

CONCLUSIONS

Withdrawal of PCP and reduced food access increased impulsivity for SACC or PCP, respectively. Impulsivity is a sensitive indicator of drug dependence.

Effects of chronic administration of drugs of abuse on impulsive choice (delay discounting) in animal models

Drug-addicted individuals show high levels of impulsive choice, characterized by preference for small immediate over larger but delayed rewards. Although the causal relationship between chronic drug use and elevated impulsive choice in humans has been unclear, a small but growing body of literature over the past decade has shown that chronic drug administration in animal models can cause increases in impulsive choice, suggesting that a similar causal relationship may exist in human drug users. This article reviews this literature, with a particular focus on the effects of chronic cocaine administration, which have been most thoroughly characterized. The potential mechanisms of these effects are described in terms of drug-induced neural alterations in ventral striatal and prefrontal cortical brain systems. Some implications of this research for pharmacological treatment of drug-induced increases in impulsive choice are discussed, along with suggestions for future research in this area.

Evaluation of behavioral impulsivity and aggression tasks as endophenotypes for borderline personality disorder

Borderline personality disorder (BPD) is marked by aggression and impulsive, often self-destructive behavior. Despite the severe risks associated with BPD, relatively little is known about the disorder's etiology. Identification of genetic correlates (endophenotypes) of BPD would improve the prospects of targeted interventions for more homogeneous subsets of borderline patients characterized by specific genetic vulnerabilities. The current study evaluated behavioral measures of aggression and impulsivity as potential endophenotypes for BPD. Subjects with BPD (N=127), a non cluster B personality disorder (OPD N=122), or healthy volunteers (HV N=112) completed self report and behavioral measures of aggression, motor impulsivity and cognitive impulsivity. Results showed that BPD subjects demonstrated more aggression and motor impulsivity than HV (but not OPD) subjects on behavioral tasks. In contrast, BPD subjects self-reported more impulsivity and aggression than either comparison group. Subsequent analyses showed that among BPD subjects behavioral aggression was associated with self-reported aggression, while behavioral and self-report impulsivity measures were more modestly associated. Overall, the results provide partial support for the use of behavioral measures of aggression and motor impulsivity as endophenotypes for BPD, with stronger support for behavioral aggression measures as an endophenotype for aggression within BPD samples.

[Attention-deficit/hyperactivity disorder. Clinical and treatment aspects]

Attention-Deficit / Hyperactivity Disorder (ADHD) is a complex disorder. The onset of the disease is in childhood. The most important symptoms of ADHD are hyperactive, impulsive and inattention symptoms. In addition, children with this syndrome often have difficulties with other aspects of their learning, emotional modulation, organization, motivation, memory and other functions of the brain's management system. Drug medications, behavioral treatment and behavioral interventions at school are the most important aspects of treatment for ADHD syndrome.

Increased sensitivity to the disinhibiting effects of alcohol in adults with ADHD

The acute impairing effects of alcohol on inhibitory control have been well documented in healthy drinkers. By contrast, little is known about alcohol effects in individuals with disorders characterized by poor impulse control, such as those with attention-deficit/hyperactivity disorder (ADHD). Alcohol could produce greater inhibitory impairment in these individuals. The present study tested this hypothesis in adults with ADHD (n=10) and controls (n=12) using the cued go/no-go task. The task requires quick responses to go targets and suppression of responses to no-go targets following the presentation of cues. Prior research on healthy adults has shown that valid cues can protect against alcohol impairment (Marczinski & Fillmore, 2003). Performance was tested under 3 doses of alcohol: 0.65 g/kg, 0.45 g/kg, and 0.0 g/kg (placebo). Alcohol dose-dependently increased inhibitory failures in controls in the invalid, but not the valid, cue condition. By contrast, those with ADHD displayed significant alcohol impairment regardless of cue condition. Thus, unlike controls, valid cues offered little protection from the disinhibiting effects of alcohol in drinkers with ADHD, suggesting an increased sensitivity to alcohol impairment of inhibitory control.

High risk behaviours following alcohol use in alcohol dependent men

BACKGROUND & OBJECTIVE

Heavy alcohol drinking and propensity to risk taking behaviour may both be associated with the occurrence of high risk behaviour. The present study was carried out to examine the association between high risk behaviours and alcohol abuse among patients admitted to an inpatient facility for treatment of alcohol dependence syndrome.

METHODS

Using event analysis technique, the prevalence and type of high risk behaviour as a consequence of a heavy drinking episode was identified among heavy drinkers. Four types of high risk behaviour namely road traffic accidents, violence, self-injurious and risky sexual behaviour were studied. Patients with and without high risk behaviour were compared on measures of severity of drinking, sensation seeking and impulsivity using addiction severity index, sensation seeking scale and Baratt's impulsivity scale respectively.

RESULTS

In 300 subjects with alcohol dependence syndrome, the most common high risk behaviour was road traffic accident following alcohol use. In 193 (64.3%) subjects heavy drinking episode was associated with high risk behaviours. Compared to those without high risk behaviours, the subjects with high risk behaviours had higher scores on sensation seeking scale and addiction severity index.

INTERPRETATION & CONCLUSION

Our findings indicated that there was a high prevalence of high risk behaviour following an episode of heavy drinking in male patients with alcohol dependence syndrome. Both, severity of drinking and personality factors were associated with the occurrence of high risk behaviour as a consequence of heavy drinking.

Conceptualizing impulsivity and risk taking in bipolar disorder: importance of history of alcohol abuse

BACKGROUND

Elevated levels of impulsivity and increased risk taking are thought to be core features of both bipolar disorder (BD) and addictive disorders. Given the high rates of comorbid alcohol abuse in BD, alcohol addiction may exacerbate impulsive behavior and risk-taking propensity in BD. Here we examine multiple dimensions of impulsivity and risk taking, using cognitive tasks and self-report measures, in BD patients with and without a history of alcohol abuse.

METHODS

Thirty-one BD subjects with a prior history of alcohol abuse or dependence (BD-A), 24 BD subjects with no history of alcohol abuse/dependence (BD-N), and 25 healthy control subjects (HC) were assessed with the Barratt Impulsiveness Scale (BIS) and the computerized Balloon Analogue Risk Task (BART).

RESULTS

Both BD groups scored significantly higher than controls on the BIS. In contrast, only the BD-A group showed impaired performance on the BART. BD-A subjects popped significantly more balloons than the BD-N and HC groups. In addition, subjects in the BD-A group failed to adjust their performance after popping balloons. Severity of mood symptomatology was not associated with performance on either task.

DISCUSSION

The current study supports a primary role of prior alcohol abuse in risk-taking propensity among patients with bipolar disorder. In addition, findings suggest that impulsivity and risky behavior, as operationalized by self-report and experimental cognitive probes, respectively, are separable constructs that tap distinct aspects of the bipolar phenotype.

Acute alcohol intoxication

Acute alcohol intoxication is a clinically harmful condition that usually follows the ingestion of a large amount of alcohol. Clinical manifestations are heterogeneous and involve different organs and apparatuses, with behavioral, cardiac, gastrointestinal, pulmonary, neurological, and metabolic effects. The management of an intoxicated patient occurs mainly in the emergency department and is aimed at stabilizing the clinical condition of the patient, depending on his/her clinical presentation. One specific drug that is useful in the treatment of acute alcohol intoxication is metadoxine, which is able to accelerate ethanol excretion. In patients presenting an acute alcohol intoxication, alcohol-related disorders should be detected so that the patient can be directed to an alcohol treatment unit, where a personalized, specific treatment can be established.

The role of impulsive behavior in drug abuse

BACKGROUND

Impulsivity is a multifaceted construct that has recently been recognized as a factor contributing to enhanced vulnerability to drug abuse.

OBJECTIVES

In the present review, we focus on two facets of impulsivity (and tasks that measure them): (1) impulsive choice (delay discounting task) and (2) inhibitory failure (go/no-go, stop signal reaction time, and five-choice serial reaction time tasks). We also describe how performance on each of these tasks is associated with drug-related behavior during phases of drug abuse that capture the essential features of addiction (acquisition, escalation, and reinstatement of drug-seeking after drug access has terminated). Three hypotheses (H) regarding the relationship between impulsivity and drug abuse are discussed: (1) increased levels of impulsivity lead to drug abuse (H1), (2) drugs of abuse increase impulsivity (H2), and (3) impulsivity and drug abuse are associated through a common third factor (H3).

CONCLUSION

Impulsivity expressed as impulsive choice or inhibitory failure plays a role in several key transition phases of drug abuse. There is evidence to support all three nonexclusive hypotheses. Increased levels of impulsivity lead to acquisition of drug abuse (H1) and subsequent escalation or dysregulation of drug intake. Drugs of abuse may increase impulsivity (H2), which is an additional contributor to escalation/dysregulation. Abstinence, relapse, and treatment may be influenced by both H1 and H2. In addition, there is a relationship between impulsivity and other drug abuse vulnerability factors, such as sex, hormonal status, reactivity to nondrug rewards, and early environmental experiences that may impact drug intake during all phases of addiction (H3). Relating drug abuse and impulsivity in phases of addiction via these three hypotheses provides a heuristic model from which future experimental questions can be addressed.

Impairment in the achievement domain in bipolar spectrum disorders: role of behavioral approach system hypersensitivity and impulsivity

AIM

Research indicates that bipolar disorder is characterized by both high levels of impairment and high levels of achievement. A critical, and yet largely unexamined question, is: what psychological mechanisms promote high accomplishment (and low impairment) among bipolar spectrum individuals? The aim of this study was to examine this question. The Authors also conceptually explore how the answer to this question can enhance the development of intervention and prevention strategies for adolescents with a bipolar spectrum condition.

METHODS

Academic transcript data were obtained for 120 college students who had either a bipolar spectrum disorder (N=54) or no major psychopathology (N=66).

RESULTS

Bipolar spectrum individuals obtained a lower cumulative grade point average (GPA, t=-2.9, P=0.005) and dropped more classes (t=2.1, P=or<0.04) than normal controls. The findings also have relevance to the behavioral approach system (BAS) dysregulation theory of bipolar disorder, as well as research on impulsivity among bipolar individuals. Specifically, follow-up analyses revealed that bipolar individuals exhibiting a combination of high BAS drive and low impulsivity earned higher GPAs than the remaining bipolar individuals. Thus, high BAS sensitivity, when paired with low impulsivity, may not be impairing and may contribute to the high achievement sometimes observed among bipolar individuals.

CONCLUSION

Such information is important for the development of prevention and intervention programs designed adolescents that lower risk for bipolar impairment without decreasing achievement.

Impulsivity as a vulnerability marker for substance-use disorders: review of findings from high-risk research, problem gamblers and genetic association studies

There is a longstanding association between substance-use disorders (SUDs) and the psychological construct of impulsivity. In the first section of this review, personality and neurocognitive data pertaining to impulsivity will be summarised in regular users of four classes of substance: stimulants, opiates, alcohol and 3,4-methylenedioxymethamphetamine (MDMA). Impulsivity in these groups may arise via two alternative mechanisms, which are not mutually exclusive. By one account, impulsivity may occur as a consequence of chronic exposure to substances causing harmful effects on the brain. By the alternative account, impulsivity pre-dates SUDs and is associated with the vulnerability to addiction. We will review the evidence that impulsivity is associated with addiction vulnerability by considering three lines of evidence: (i) studies of groups at high-risk for development of SUDs; (ii) studies of pathological gamblers, where the harmful consequences of the addiction on brain structure are minimised, and (iii) genetic association studies linking impulsivity to genetic risk factors for addiction. Within each of these three lines of enquiry, there is accumulating evidence that impulsivity is a pre-existing vulnerability marker for SUDs.

Are all drug addicts impulsive? Effects of antisociality and extent of multidrug use on cognitive and motor impulsivity

The purpose of this investigation was to examine the influence of antisociality and extent of multidrug use on cognitive and motor impulsivity among substance-dependent individuals (SDIs) that used primarily cocaine and/or heroin. One hundred currently abstinent male SDIs participated in the study. Extent of multidrug use and degree of antisociality, assessed with the Socialization Scale of the California Psychological Inventory (So-CPI), were used to classify participants into one of four groups: high antisocial/low multidrug use, high antisocial/high multidrug use, low antisocial/low multidrug use, and low antisocial/high multidrug use. All subjects completed the Iowa Gambling Task to assess cognitive impulsivity and the Stroop Task to measure motor impulsivity. Contrary to expectations, antisociality was associated with more advantageous performance on the Iowa Gambling Task, independent of extent of multidrug use. In contrast, greater multidrug use was associated with general psychomotor slowing on the Stroop Task. Results suggest that a subclinical form of antisociality may have a paradoxically facilitating effect on decision-making and cognitive impulsivity among SDIs.

MAOA deficiency and abnormal behaviour: perspectives on an association

We have recently described an association between abnormal behaviour and monoamine oxidase A (MAOA) deficiency in several males from a single large Dutch kindred. Affected males differed from unaffected males by borderline mental retardation and increased impulsive behaviour (aggressive behaviour, abnormal sexual behaviour and arson). Nevertheless, a specific psychiatric diagnosis was not made in four affected males who had psychiatric examination. Since MAOA deficiency raises 5-hydroxytryptamine (5-HT) levels, it provides an interesting exception to the low 5-HT paradigm of impulsive aggression. Even if the possible relationship between MAOA deficiency and abnormal behaviour is confirmed in other kindreds, the data do not support the hypothesis that MAOA constitutes an "aggression gene'. In fact, because genes are essentially simple and behaviour is by definition complex, a direct causal relationship between a single gene and a specific behaviour is highly unlikely. In the case of MAOA deficiency, some of the complexities are illustrated by the variability in the behavioural phenotype, as well as by the highly complex effects of MAOA deficiency on neurotransmitter function. Thus, the concept of a gene that directly encodes behaviour is unrealistic.

Impulsivity and risk-taking behavior in focal frontal lobe lesions

Frontal lobe dysfunction may underlie excessively impulsive and risky behavior observed in a range of neurological disorders. We devised a gambling task to examine these behavior tendencies in a sample of patients who had sustained focal damage to the frontal lobes or nonfrontal cortical regions as well as in a matched sample of healthy control subjects. The main objectives of the study were: (1) to behaviorally dissociate impulsivity and risk-taking; (2) to examine potential associations between specific frontal lesion sites and impulsivity or risk-taking; (3) to investigate the influence of reinforcement and trial timing on both behaviors. Our results indicated that patients and controls were equally likely to perform impulsively. Risk-taking performance strategies, however, were related to left ventrolateral and orbital lesion sites. Moreover, risk-taking was also associated with blunted response alteration following a nonrewarded trial. Patients and control subjects showed identical responses to reward-timing manipulations consistent with formal decision-making theory. These findings suggest that ventrolateral and orbital lesions are related to the reward-based aspects of decision-making (risk-taking) rather than to simple response disinhibition (impulsivity). Reduced reaction to the negative consequences of one's actions may underlie this behavior pattern.

New onset heightened interest or drive for gambling, shopping, eating or sexual activity in patients with Parkinson's disease: the role of dopamine agonist treatment and age at motor symptoms onset

Alterations of impulse control that have recently been associated with Parkinson's disease (PD) are serious behavioural disturbances with significant impact on PD patients and their families.A total of 193 consecutive PD patients with no history of psychiatric illness and 190 age/gender-matched healthy controls were queried on the presence of new onset heightened interest or drive for gambling, shopping, eating or sexual activity (GSES). Clinical data were retrieved from medical charts and interviews. logistic regressions models assessed risk factors for these specific troublesome behaviours. New or heightened interests or drives for GSES behaviours were reported by 27 patients (14% vs 0% for controls). Younger age at PD motor symptoms onset (OR = 0.99, p = 0.0172), male gender (OR = 1.10, p = 0.0576) and longer duration of treatment with dopamine agonists (DAs)(OR = 1.18, >/=6 years versus never treated, p = 0.0459) contributed additively to the risk of developing one or more of these behavioural features. New onset heightened interests or drives for GSES are not rare behavioural disturbances among patients with PD. Age, gender and duration of treatment with DAs have an independent and additive effect on the risk to develop such behavioural changes. Patients should be informed about potential treatment-associated behavioural changes.

Impulsive behavior in adults with attention deficit/ hyperactivity disorder: characterization of attentional, motor and cognitive impulsiveness

Attention-deficit/hyperactivity disorder (ADHD) is characterized by inattention and/or hyperactivity/impulsivity. Impulsivity persists in adults with ADHD and might be the basis of much of the impairment observed in the daily lives of such individuals. The objective of this study was to address the presence, and more importantly, the three dimensions of impulsivity: attentional, non-planning and motor, in how they may relate to neuropsychological mechanisms of impulse control. We studied a sample of 50 adults with ADHD and 51 healthy comparison controls using the Barratt Impulsivity Scale Version 11 (BIS), and neuropsychological tasks, namely the Continuous Performance Task (CPT-II) and the Iowa Gambling Task (IGT). The ADHD group showed more signs of impulsivity on the three dimensions of BIS, committed more errors of omission and commission on the CPT-II, and made more disadvantageous choices on the IGT. These results support the existence of deficits related to three components of impulsivity: motor, cognitive, and attentional among adults with ADHD. Most importantly, this study also highlights the complementary nature of self-report questionnaires and neuropsychological tasks in the assessment of impulsivity in ADHD adults.