Jasmin Vassileva

Psychopathy versus psychopathies in classifying criminal offenders

Purpose. Psychopathy has been shown to be related to the onset, frequency, and course of antisocial behaviour in criminal offenders. The purpose of the present study was to use cluster analysis to explore the existence of subtypes of criminal offenders in male inmates, based on the two empirically validated dimensions of psychopathy and several other dimensions previously proposed for differentiating offender groups. Methods. Two hundred male inmates participated in the study. Scores on the two dimensions of the Psychopathy Checklist–Revised (Hare, 1991), the Interpersonal Measure of Psychopathy (Kosson, Steuerwald, Forth, & Kirkhart, 1997), DSM-IV diagnoses for alcohol and drug abuse/dependence, and anxiety were standardized and were included in two different types of cluster analyses. Both Wards hierarchical method and K-means non-hierarchical method revealed the presence of four subtypes of criminal offenders in the sample. The four-cluster solution was replicated when the sample was split in half and identical cluster analyses were performed on the two subsamples. Results. Two types of cluster analyses identified four subtypes of criminal offenders in two samples of jail inmates. Two of the clusters resembled primary and secondary psychopaths described in the literature, the third group exhibited some antisocial and psychopathic features, and the fourth group was non-psychopathic. Conclusions. Findings suggest that considering the individual contributions of the two dimensions of psychopathy in lieu of the construct as a whole may prove useful in identifying relatively homogeneous groups of criminal offenders.

The influence of executive functions, sensation seeking, and HIV serostatus on the risky sexual practices of substance-dependent individuals

From a public health standpoint, identifying factors that contribute to risky sexual practices among substance-dependent individuals is critical, particularly in the context of HIV infection. This study examines the respective contributions of executive neurocognitive functions, sensation seeking, and HIV serostatus in predicting risky sexual practices among poly-substance users (with a history of dependence primarily for cocaine or cocaine/heroin). HIV+ (n=109) and HIV- (n=154) substance-dependent individuals were assessed using three neurocognitive tasks of executive functions: Stroop reaction time, delayed non-matching to sample, and the Iowa Gambling Task. Sensation seeking was assessed using the Sensation Seeking Scale-V. Greater sensation seeking was associated with more risky sexual practices among HIV+ participants, particularly among those who performed best on the Iowa Gambling Task. Our findings indicate that continued risk behavior among HIV+ drug users may be driven by sensation seeking (a personality trait common among drug users); however, the impact of executive functions is less clear.

Performance of young adult cannabis users on neurocognitive measures of impulsive behavior and their relationship to symptoms of cannabis use disorders

Recent studies suggest that abstinent cannabis users show deficits on neurocognitive laboratory tasks of impulsive behavior. But results are mixed, and less is known on the performance of non-treatment-seeking, young adult cannabis users. Importantly, relationships between performance on measures of impulsive behavior and symptoms of cannabis addiction remain relatively unexplored. We compared young adult current cannabis users (CU, n = 65) and nonusing controls (NU, n = 65) on several laboratory measures of impulsive behavior, as well as on a measure of episodic memory commonly impacted by cannabis use. The CU group performed more poorly than the NU group on the Hopkins Verbal Learning Test–Revised Total Immediate Recall and Delayed Recall. No significant differences were observed on the measures of impulsive behavior (i.e., Iowa Gambling Task, IGT; Go–Stop Task; Monetary Choice Questionnaire; Balloon Analogue Risk Task). We examined relationships between neurocognitive performance and symptoms of cannabis use disorder symptoms (Diagnostic and Statistical Manual of Mental Disorders–Fourth Edition, DSM–IV CUD) among the CU group, which revealed that poorer IGT performance was associated with more symptoms of DSM–IV CUD. Our results show poorer memory performance among young adult cannabis users than among healthy controls, but no differences on measures of impulsive behavior. However, performance on a specific type of impulsive behavior (i.e., poorer decision making) was associated with more cannabis use disorder symptoms. These results provide preliminary evidence to suggest that decision-making deficits may be more strongly associated with problems experienced from cannabis use, rather than solely being a consequence of cannabis use, per se. This publication was supported by Grants K23DA023560 and R01DA031176 (PI: Gonzalez) and F31DA032244 (PI: Schuster) from the National Institute on Drug Abuse (NIDA), as well as P01 CA098262 (PI: Mermelstein) from the National Cancer Institute (NCI). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Institutes of Health.

Decision-making in stimulant and opiate addicts in protracted abstinence: evidence from computational modeling with pure users

Substance dependent individuals (SDI) often exhibit decision-making deficits; however, it remains unclear whether the nature of the underlying decision-making processes is the same in users of different classes of drugs and whether these deficits persist after discontinuation of drug use. We used computational modeling to address these questions in a unique sample of relatively “pure” amphetamine-dependent (N = 38) and heroin-dependent individuals (N = 43) who were currently in protracted abstinence, and in 48 healthy controls (HC). A Bayesian model comparison technique, a simulation method, and parameter recovery tests were used to compare three cognitive models: (1) Prospect Valence Learning with decay reinforcement learning rule (PVL-DecayRI), (2) PVL with delta learning rule (PVL-Delta), and (3) Value-Plus-Perseverance (VPP) model based on Win-Stay-Lose-Switch (WSLS) strategy. The model comparison results indicated that the VPP model, a hybrid model of reinforcement learning (RL) and a heuristic strategy of perseverance had the best post-hoc model fit, but the two PVL models showed better simulation and parameter recovery performance. Computational modeling results suggested that overall all three groups relied more on RL than on a WSLS strategy. Heroin users displayed reduced loss aversion relative to HC across all three models, which suggests that their decision-making deficits are longstanding (or pre-existing) and may be driven by reduced sensitivity to loss. In contrast, amphetamine users showed comparable cognitive functions to HC with the VPP model, whereas the second best-fitting model with relatively good simulation performance (PVL-DecayRI) revealed increased reward sensitivity relative to HC. These results suggest that some decision-making deficits persist in protracted abstinence and may be mediated by different mechanisms in opiate and stimulant users.

Neuropsychological functioning in a cohort of HIV- and hepatitis C virus-infected women.

Objective:To evaluate the neurocognitive function in 220 women enrolled in the Womens Interagency HIV Study (WIHS), a study of disease progression in women living with HIV/AIDS and in HIV-negative controls. Methods:We evaluated the prevalence of abnormal neuropsychological (NP) results in hepatitis C virus (HCV)-positive compared with HCV-negative women in combination with HIV serostatus. Results:NP impairment was significantly higher for HCV-positive women in comparison with HCV-negative women [odds ratio (OR), 2.03; 95% confidence interval (CI), 1.17–3.51]. Women co-infected with HCV and HIV demonstrated greater abnormal NP performance than those not infected with either, particularly if there was evidence of CD4 T-lymphocyte immunosuppression [> 200 × 106 CD4 cells/l (OR, 3.48; 95% CI, 1.49–8.15) and ≤ 200 × 106 CD4 cells/l (OR, 5.38; 95% CI, 1.46–19.84)]. Women who were HCV-positive/HIV-positive and not taking antiretroviral therapy (ART) were more likely (OR, 7.03; 95% CI, 2.63–18.82) to demonstrate NP impairment than those who were HCV-negative/HIV-negative. In analyses controlling separately for education, intelligence quotient, depression, sedating drug use, head injury, ethnicity, and history of substance use, HCV continued to significantly predict NP impairment. The HCV effect did not reach significance when controlling for age in bivariate or multivariate analyses although the odds ratio for NP abnormalities in HCV-infected patients was only slightly reduced (ORs above 1.9). After testing for an interaction between age and infection status, we conducted age-stratified analysis and showed a significant effect of infection status for those aged under 40 years. Conclusions:The effect of aging on co-infected populations will require further study. This study has demonstrated the association of HCV with the risk of neurocognitive impairment in women living with HIV/AIDS and suggests that co-infection has an additive effect.

Computational Modeling Reveals Distinct Effects of HIV and History of Drug Use on Decision-Making Processes in Women

Objective Drug users and HIV-seropositive individuals often show deficits in decision-making; however the nature of these deficits is not well understood. Recent studies have employed computational modeling approaches to disentangle the psychological processes involved in decision-making. Although such approaches have been used successfully with a number of clinical groups including drug users, no study to date has used computational modeling to examine the effects of HIV on decision-making. In this study, we use this approach to investigate the effects of HIV and drug use on decision-making processes in women, who remain a relatively understudied population. Method Fifty-seven women enrolled in the Womens Interagency HIV Study (WIHS) were classified into one of four groups based on their HIV status and history of crack cocaine and/or heroin drug use (DU): HIV+/DU+ (n = 14); HIV+/DU− (n = 17); HIV−/DU+ (n = 14); and HIV−/DU− (n = 12). We measured decision-making with the Iowa Gambling Task (IGT) and examined behavioral performance and model parameters derived from the best-fitting computational model of the IGT. Results Although groups showed similar behavioral performance, HIV and DU exhibited differential relationship to model parameters. Specifically, DU was associated with compromised learning/memory and reduced loss aversion, whereas HIV was associated with reduced loss aversion, but was not related to other model parameters. Conclusions Results reveal that HIV and DU have differential associations with distinct decision-making processes in women. This study contributes to a growing line of literature which shows that different psychological processes may underlie similar behavioral performance in various clinical groups and may be associated with distinct functional outcomes.

HIV+ men and women show different performance patterns on procedural learning tasks

The literature suggests that nondeclarative, or nonconscious, learning might be impaired among HIV-seropositive (HIV+) individuals compared with HIV-seronegative (HIV–) matched control groups, but these studies have included relatively few women. We administered measures of motor skill and probabilistic learning, tasks with a nondeclarative or procedural learning component that are dependent on integrity of prefrontal-striatal systems, to well-matched groups of 148 men and 65 women with a history of substance dependence that included 45 men and 30 women seropositive for HIV. All participants were abstinent at testing. Compared to HIV– women, HIV+ women performed significantly more poorly on both tasks, but HIV+ mens performance did not differ significantly from that of HIV– men on either task. These different patterns of performance indicate that features of HIV-associated neurocognitive disorder (HAND) cannot always be generalized from men to women. Additional studies are needed to address directly the possibility of sex differences in HAND and the possibility that women might be more vulnerable to the effects of HIV and substance dependence on some neurocognitive functions.

Deficits in complex motor functions, despite no evidence of procedural learning deficits, among HIV+ individuals with history of substance dependence.

Human immunodeficiency virus (HIV) and drugs of abuse affect common neural systems underlying procedural memory, including the striatum. The authors compared performance of 48 HIV seropositive (HIV+) and 48 HIV seronegative (HIV-) participants with history of cocaine and/or heroin dependence across multiple Trial Blocks of three procedural learning (PL) tasks: Rotary Pursuit (RP), Mirror Star Tracing (MST), and Weather Prediction (WP). Groups were well matched on demographic, psychiatric, and substance use parameters, and all participants were verified abstinent from drugs. Mixed model analyses of variance revealed that the individuals in the HIV+ group performed more poorly across all tasks, with a significant main effect of HIV serostatus observed on the Mirror Star Tracing and a trend toward significance obtained for the Rotary Pursuit task. No significant differences were observed on the Weather Prediction task. Both groups demonstrated significant improvements in performance across all three procedural learning tasks. It is important to note that no significant Serostatus x Trial Block interactions were observed on any task. Thus, the individuals in the HIV+ group tended to perform worse than those in the HIV- group across all trial blocks of procedural learning tasks with motor demands, but showed no differences in their rate of improvement across all tasks. These findings are consistent with HIV--associated deficits in complex motor skills, but not in procedural learning.

Machine-learning identifies substance-specific behavioral markers for opiate and stimulant dependence

BACKGROUND Recent animal and human studies reveal distinct cognitive and neurobiological differences between opiate and stimulant addictions; however, our understanding of the common and specific effects of these two classes of drugs remains limited due to the high rates of polysubstance-dependence among drug users. METHODS The goal of the current study was to identify multivariate substance-specific markers classifying heroin dependence (HD) and amphetamine dependence (AD), by using machine-learning approaches. Participants included 39 amphetamine mono-dependent, 44 heroin mono-dependent, 58 polysubstance dependent, and 81 non-substance dependent individuals. The majority of substance dependent participants were in protracted abstinence. We used demographic, personality (trait impulsivity, trait psychopathy, aggression, sensation seeking), psychiatric (attention deficit hyperactivity disorder, conduct disorder, antisocial personality disorder, psychopathy, anxiety, depression), and neurocognitive impulsivity measures (Delay Discounting, Go/No-Go, Stop Signal, Immediate Memory, Balloon Analogue Risk, Cambridge Gambling, and Iowa Gambling tasks) as predictors in a machine-learning algorithm. RESULTS The machine-learning approach revealed substance-specific multivariate profiles that classified HD and AD in new samples with high degree of accuracy. Out of 54 predictors, psychopathy was the only classifier common to both types of addiction. Important dissociations emerged between factors classifying HD and AD, which often showed opposite patterns among individuals with HD and AD. CONCLUSIONS These results suggest that different mechanisms may underlie HD and AD, challenging the unitary account of drug addiction. This line of work may shed light on the development of standardized and cost-efficient clinical diagnostic tests and facilitate the development of individualized prevention and intervention programs for HD and AD.

Decision making among HIV+ drug using men who have sex with men: A preliminary report from the Chicago Multicenter AIDS Cohort Study

HIV+ substance-dependent individuals (SDIs) make significantly poorer decisions than HIV– SDIs, but the neurocognitive mechanisms underlying this impairment have not been identified. We administered the Iowa Gambling Task (IGT), a measure of decision making under uncertain risk, and the Cups Task, a measure of decision making under specified risk, to a group of 56 HIV+ and 23 HIV– men who have sex with men (MSMs) with a history of substance dependence enrolled in the Multicenter AIDS Cohort Study. The IGT provides no explicit information regarding the contingencies for each possible choice, and the probability of each outcome remains ambiguous at least for the early trials; in contrast, the Cups Task provides explicit information about the probability of each outcome. The HIV+ group made significantly poorer decisions on the IGT than the HIV– group. Cups Task performance did not differ significantly between HIV– and HIV+ groups. Exploratory analyses of the IGT data suggested that HIV+ subjects tended to perform more poorly during the early learning phase when uncertainty about specific outcomes was greatest. Additionally, performance on the final two trial blocks was significantly correlated with Stroop Interference scores, suggesting that IGT performance is driven increasingly by executive control during the later portion of the task. Potential cognitive mechanisms to be explored in later studies are discussed, including impairment in implicit learning processing.