Aberrant glutamatergic systems underlying impulsive behaviors: Insights from clinical and preclinical research.

Impulsivity is a broad construct that often refers to one of several distinct behaviors and can be measured with self-report questionnaires and behavioral paradigms. Several psychiatric conditions are characterized by one or more forms of impulsive behavior, most notably the impulsive/hyperactive subtype of attention-deficit/hyperactivity disorder (ADHD), mood disorders, and substance use disorders. Monoaminergic neurotransmitters are known to mediate impulsive behaviors and are implicated in various psychiatric conditions. However, growing evidence suggests that glutamate, the major excitatory neurotransmitter of the mammalian brain, regulates important functions that become dysregulated in conditions like ADHD. The purpose of the current review is to discuss clinical and preclinical evidence linking glutamate to separate aspects of impulsivity, specifically motor impulsivity, impulsive choice, and affective impulsivity. Hyperactive glutamatergic activity in the corticostriatal and the cerebro-cerebellar pathways are major determinants of motor impulsivity. Conversely, hypoactive glutamatergic activity in frontal cortical areas and hippocampus and hyperactive glutamatergic activity in anterior cingulate cortex and nucleus accumbens mediate impulsive choice. Affective impulsivity is controlled by similar glutamatergic dysfunction observed for motor impulsivity, except a hyperactive limbic system is also involved. Loss of glutamate homeostasis in prefrontal and nucleus accumbens may contribute to motor impulsivity/affective impulsivity and impulsive choice, respectively. These results are important as they can lead to novel treatments for those with a condition characterized by increased impulsivity that are resistant to conventional treatments.

Glycated hemoglobin, type 2 diabetes, and poor diabetes control are positively associated with impulsivity changes in aged individuals with overweight or obesity and metabolic syndrome.

Impulsivity has been proposed to have an impact on glycemic dysregulation. However, it remains uncertain whether an unfavorable glycemic status could also contribute to an increase in impulsivity levels. This study aims to analyze associations of baseline and time-varying glycemic status with 3-year time-varying impulsivity in older adults at high risk of cardiovascular disease. A 3-year prospective cohort design was conducted within the PREDIMED-Plus-Cognition substudy. The total population includes 487 participants (mean age = 65.2 years; female = 50.5%) with overweight or obesity and metabolic syndrome. Insulin resistance (HOMA-IR), glycated hemoglobin (HbA1c), presence of type 2 diabetes mellitus, and type 2 diabetes control were evaluated. Impulsivity was measured using the Impulsive Behavior Scale questionnaire and various cognitive measurements. Impulsivity z-scores were generated to obtain Global, Trait, and Behavioral Impulsivity domains. Linear mixed models were used to study the longitudinal associations across baseline, 1-year, and 3-year follow-up visits. HOMA-IR was not significantly related to impulsivity. Participants with higher HbA1c levels, type 2 diabetes, and poor control of diabetes showed positive associations with the Global Impulsivity domain over time, and those with higher HbA1c levels were further related to increases in the Trait and Behavioral Impulsivity domains over the follow-up visits. These results suggest a potential positive feedback loop between impulsivity and glycemic-related dysregulation.

Impulsivity as a predictor of clinical and psychological outcomes in a naturalistic prospective cohort of subjects at ultra-high risk (UHR) for psychosis from Tunisia.

BACKGROUND: Impulsivity is associated with serious detrimental consequences on physical, mental, behavioral and social aspects of health among patients with psychosis. The present prospective 12-month follow-up study aimed to determine the prevalence of highly impulsive individuals among Ultra High Risk (UHR) patients, how impulsivity evolves over the follow-up period, and whether impulsivity impacts clinical, psychological and functional outcomes in this population. METHOD: UHR patients were invited to complete a battery of measurements at three-time points: at baseline, and at 6 and 12 months of follow-up. Impulsivity was assessed using both behavioral (the Wisconsin Card Sorting Test, WCST) and self-report (the Barratt Impulsiveness Scale, BIS-11) measures. RESULTS: Findings showed that at 6 months of follow-up, higher 6-month BIS-11 attentional and motor impulsivity were significantly associated with lower quality of life and greater general psychological distress. In addition, higher baseline BIS-11 motor impulsivity significantly predicted more severe positive psychotic symptoms at 12 months of follow-up. However, WCST scores did not show any significant associations with study variables at the different times of follow-up. CONCLUSION: Interventions targeting impulsivity in UHR individuals could help decrease psychological distress and positive psychotic symptoms' severity, as well as improve quality of life in UHR individuals.

Hyped-up or meditate: A scoping review of mindfulness-based group interventions for adolescents with attention deficit hyperactivity disorder.

The objective of this scoping review is to evaluate the effectiveness of mindfulness training in improving functioning in adolescents (aged 12-19 years) diagnosed with Attention Deficit Hyperactivity Disorder (ADHD). Previous research has demonstrated that psychological interventions improve functioning in a myriad of domains for individuals diagnosed with ADHD, such as attention training, interpersonal relationships, and social skills. Mindfulness-based interventions (MBI) are indicated as an intervention in attention training. It maybe argued that group based MBI programmes should begin early, for children and adolescents at a time that is critical in their development. Methods and reporting are in line with the PRISMA extension for scoping reviews, the protocol is preregistered in the (Open Science Framework register). The study outcomes included attention, impulsivity, and relationships of adolescents with ADHD. Findings demonstrated preliminary evidence for the use of group-based mindfulness interventions with adolescents continues to be nascent. Although studies reported positive results, the evidence of its effectiveness for adolescents with ADHD is inconclusive, due to limited studies available and the limitations of the study design. This scoping review provides a panorama of MBI for ADHD adolescents.

This review explores group mindfulness-based programmes for adolescents with attention deficit hyperactive disorders. It provides a useful summary for clinicians.

Trajectory Analysis for Identifying Classes of Attention Deficit Hyperactivity Disorder (ADHD) in Children of the United States.

Background: Attention Deficit Hyperactivity Disorder (ADHD) is a mental health disorder that affects attention and behavior. People with ADHD frequently encounter challenges in social interactions, facing issues, like social rejection and difficulties in interpersonal relationships, due to their inattention, impulsivity, and hyperactivity. Methods: A National Longitudinal Survey of Youth (NLSY) database was employed to identify patterns of ADHD symptoms. The children who were born to women in the NLSY study between 1986 and 2014 were included. A total of 1,847 children in the NLSY 1979 cohort whose hyperactivity/inattention score was calculated when they were four years old were eligible for this study. A trajectory modeling method was used to evaluate the trajectory classes. Sex, baseline antisocial score, baseline anxiety score, and baseline depression score were adjusted to build the trajectory model. We used stepwise multivariate logistic regression models to select the risk factors for the identified trajectories. Results: The trajectory analysis identified six classes for ADHD, including (1) no sign class, (2) few signs since preschool being persistent class, (3) few signs in preschool but no signs later class, (4) few signs in preschool that magnified in elementary school class, (5) few signs in preschool that diminished later class, and (6) many signs since preschool being persistent class. The sensitivity analysis resulted in a similar trajectory pattern, except for the few signs since preschool that magnified later class. Children's race, breastfeeding status, headstrong score, immature dependent score, peer conflict score, educational level of the mother, baseline antisocial score, baseline anxious/depressed score, and smoking status 12 months prior to the birth of the child were found to be risk factors in the ADHD trajectory classes. Conclusion: The trajectory classes findings obtained in the current study can (a) assist a researcher in evaluating an intervention (or combination of interventions) that best decreases the long-term impact of ADHD symptoms and (b) allow clinicians to better assess as to which class a child with ADHD belongs so that appropriate intervention can be employed.

The Relevance of Hypersexuality and Impulsivity in Different Groups of Treatment-Seekers With and Without (Exclusive) Pedophilia.

Hypersexuality and impulsivity are regarded as risk factors for sexual offending against children. Studies exploring these factors in undetected men who offended or are at risk of offending are rare. This study aims to investigate hypersexuality and impulsivity in treatment-seeking men with and without a diagnosis of (exclusive) pedophilia who committed child sexual abuse (CSA), consumed child sexual abuse images (CSAI), or feel at risk of offending sexually. Data were obtained from three child abuse prevention projects in Bamberg, Germany. We employed self-report (BIS-11, HBI), objective measures (TSO), and risk assessment tools (STABLE-2007). We computed Bayesian ordinal logit and binomial generalized linear models to explore differences between groups and to predict lifetime CSA and CSAI. Hypersexuality scores were particularly pronounced in patients with exclusive and non-exclusive pedophilia. Patients without pedophilia scored similarly to nonclinical samples. Impulsivity measures did not consistently differ between groups. We could not predict lifetime CSA and CSAI using impulsivity and hypersexuality measures. Sexual rather than general impulsivity seems to be an issue in men with pedophilia. The motivation to offend in patients without pedophilia is discussed.

Triple network resting-state functional connectivity patterns of alcohol heavy drinking.

AIMS: Previous neuroimaging research in alcohol use disorder (AUD) has found altered functional connectivity in the brain's salience, default mode, and central executive (CEN) networks (i.e. the triple network model), though their specific associations with AUD severity and heavy drinking remains unclear. This study utilized resting-state fMRI to examine functional connectivity in these networks and measures of alcohol misuse. METHODS: Seventy-six adult heavy drinkers completed a 7-min resting-state functional MRI scan during visual fixation. Linear regression models tested if connectivity in the three target networks was associated with past 12-month AUD symptoms and number of heavy drinking days in the past 30 days. Exploratory analyses examined correlations between connectivity clusters and impulsivity and psychopathology measures. RESULTS: Functional connectivity within the CEN network (right and left lateral prefrontal cortex [LPFC] seeds co-activating with 13 and 15 clusters, respectively) was significantly associated with AUD symptoms (right LPFC: ß = .337, p-FDR = .016; left LPFC: ß = .291, p-FDR = .028) but not heavy drinking (p-FDR > .749). Post-hoc tests revealed six clusters co-activating with the CEN network were associated with AUD symptoms-right middle frontal gyrus, right inferior parietal gyrus, left middle temporal gyrus, and left and right cerebellum. Neither the default mode nor the salience network was significantly associated with alcohol variables. Connectivity in the left LPFC was correlated with monetary delay discounting (r = .25, p = .03). CONCLUSIONS: These findings support previous associations between connectivity within the CEN network and AUD severity, providing additional specificity to the relevance of the triple network model to AUD.

Relationship between bullying victimization and murderous behaviors and impulsivity's mediating role: Evidence from Chinese early adolescents.

BACKGROUND: Evidence suggests a robust relationship between experiencing bullying victimization (BV) and engaging in murderous behaviors among adolescents. However, the potential mediating effect of impulsivity on the relationship between BV and murderous behaviors in early adolescents remains underexplored. METHODS: A total of 5724 adolescents, with a mean age of 13.5 years, were enrolled from three middle schools in Anhui Province, China. Participants completed self-report questionnaires detailing their experiences with bullying, impulsiveness, and murderous behaviors. To assess the relationship between BV and murderous behaviors, multivariate logistic regression and Poisson regression analyses were conducted. Mediation analysis was performed using structural equation modeling. RESULTS: After controlling for confounding factors, a positive association was found between experiencing BV and engaging in murderous behaviors (p < 0.05). Mediation analysis revealed a significant indirect effect of BV on the occurrence of murderous behaviors through impulsivity (indirect effect = 0.027, 95 % CI: 0.021, 0.033). BV appears to heighten levels of impulsivity, which in turn increases the likelihood of murderous behaviors. Additionally, sex-specific analysis indicated that impulsivity played a greater mediating role in the link between verbal and relational BV and murderous behaviors in females, while physical and cyber BV were more significant in males. CONCLUSIONS: Our findings underscore the necessity of early targeted interventions for adolescents experiencing BV and exhibiting high levels of impulsivity to mitigate their risk of engaging in murderous behaviors.

Individualized prediction of online shopping addiction from whole-brain functional connectivity.

Online shopping addiction (OSA) is defined as a behavioral addiction where an individual exhibits an unhealthy and excessive attachment to shopping on the Internet. Since the OSA shown its adverse impacts on individuals' daily life and social functions, it is important to examine the neurobiological underpinnings of OSA that could be used in clinical practice to identify individuals with OSA. The present study addressed this question by employing a connectome-based prediction model approach to predict the OSA tendency of healthy subjects from whole-brain resting-state functional connectivity. The OSA connectome - a set of connections across multiple brain networks that contributed to predict individuals' OSA tendency was identified, including the functional connectivity between the frontal-parietal network (FPN) and cingulo-opercular network (CON) (i.e., positive network), as well as the functional connectivity within default mode network (DMN) and that between FPN and DMN (i.e., negative network). Key nodes that contributed to the prediction model included the middle frontal gyrus, inferior frontal gyrus, anterior cingulate cortex, and inferior temporal gyrus, which have been associated with impulsivity and emotional processing. Notably, this connectome has shown its specific role in predicting OSA by controlling for the influence of general Internet addiction. Moreover, the strength of the negative network mediated the relationship between OSA and impulsivity, highlighting that the negative network underlies the impulsivity characteristic of OSA. Together, these findings advanced our understanding of the neural correlates of OSA and provided a promising framework for diagnosing OSA.

Involvement of posterior hypothalamic CaMKII-positive neurons in ADHD-like behaviors in mice.

This study explores the behavioral effects of modulating CaMKII-positive (CaMKII+) neurons in the posterior hypothalamus (PH). Utilizing a chemogenetic approach in mice, we discovered that the activation of CaMKII + neurons within the PH is associated with heightened locomotor activity, reduced social interaction, and impulsive behavior unrelated to anxiety or avoidance. These observed behaviors share a significant resemblance with characteristics commonly found in attention deficit and hyperactivity disorder (ADHD). Notably, treatment with clonidine, which is frequently prescribed for ADHD, effectively reduced impulsive behaviors in our mouse model. Our findings uncover the role of the PH that has not been previously explored and suggest a possible involvement of the PH in the manifestation of ADHD-like behaviors.

Investigating suicidal behavior among prisoners in the light of the behavioral addiction approach: results of a multicenter cross-sectional study.

Introduction: The behavioral addiction model posits that repetitive suicidal behaviors can serve as maladaptive strategies for managing stress and negative emotional states, akin to substance addiction. Both behaviors involve negative emotions, offer temporary psychological relief, and persist, indicating shared neurobiological mechanisms. This study explored psychometric differences among major repeaters, occasional attempters, and non-suicidal prisoners. Methods: A multi-centre cross-sectional survey of 363 inmates across four prisons assessed depression, cognitive-emotional regulation, impulsivity, perceived stress, lifetime non-suicidal self-injury and suicide attempts. Results: Mild depression, moderate suicidal ideation, and moderate impulsivity were common, with nearly half of the participants having attempted suicide at least once. Hierarchical multiple regression analyses revealed that repeated suicidal behavior in the past increases susceptibility to future suicidal thoughts, with suicide attempts serving as a maladaptive emotion regulation strategy among repeated attempters. Discussion: The results reveal differences in emotional dysregulation, impulsivity, and stress coping strategies among the studied groups, reinforcing the idea of suicidality as a form of behavioral addiction. The addiction approach helps explain the sensitivity to later suicidal thoughts in former attempters and self-harmers, offering valuable insights for tailored interventions within correctional settings.

LEAP2 is associated with impulsivity and reward sensitivity depending on the nutritional status and decreases with protein intake in humans.

AIM: Liver-expressed antimicrobial peptide 2 (LEAP2) dynamics in human plasma and its association with feeding behaviour remain poorly understood. Therefore, this study aims: (a) to investigate fasting LEAP2 in participants with normal weight or with overweight or mild obesity (OW/OB); (b) to study the association between fasting LEAP2 and anthropometric and metabolic traits, feeding behaviour, LEAP2 genetic variants and blood cell DNA methylation status; and (c) to ascertain postprandial changes in LEAP2 after high protein intake and the association with feeding behaviour and food intake. METHODS: Anthropometric and behavioural measures, genotyping, methylation profiling, plasma glucose and LEAP2 concentrations were assessed in 327 females and males. A subgroup of 123 participants received an ad libitum high-protein meal, and postprandial LEAP2 concentration and behavioural measures were assessed. RESULTS: LEAP2 concentration was higher in participants with OW/OB (p < 0.001) and in females (p < 0.001), and was associated with LEAP2 single nucleotide polymorphisms rs765760 (p = 0.012) and rs803223 (p = 0.019), but not with LEAP2 methylation status. LEAP2 concentration was directly related to glycaemia (p = 0.001) and fullness (p = 0.003) in participants with normal weight, whereas it was associated with body mass index (p = 0.018), waist circumference (p = 0.014) and motor impulsivity in participants with OW/OB (p = 0.005). A negative association with reward responsiveness was observed in participants with OW/OB (p = 0.023). LEAP2 concentration was inversely associated with food intake (p = 0.034) and decreased after a high-protein meal (p < 0.001), particularly in women (p = 0.002). CONCLUSION: Increased LEAP2 in participants with OW/OB is associated with behavioural characteristics of obesity. Our results show sexual dimorphism in LEAP2 concentration before and after food intake and highlight the role of LEAP2 in feeding regulation.

Distinct patterns of hippocampal subfield volumes predict coping strategies, emotion regulation, and impulsivity in healthy adults.

BACKGROUND: Recent studies have suggested that the hippocampus (HC) is involved in cognitive and behavioral functions beyond memory. We aimed to investigate how the volume of each subfield of the HC is associated with distinct patterns of coping strategies, emotion regulation, and impulsivity in a healthy population. METHODS: We studied a total of 218 healthy subjects using the Leipzig mind-brain-body dataset. Participants were assessed for coping strategies, emotion regulation, and impulsivity using the Cognitive Emotion Regulation Questionnaire (CERQ), Coping Orientations to Problems Experienced (COPE), Impulsive Behavior Scale (UPPS), and Behavioral Activation and Inhibition System (BAS/BIS). The associations between HC subfield volumes including CA1, CA2/3, CA4/DG, SR-SL-SM, and subiculum, and behavioral scores were examined using multiple linear regression models adjusted for possible confounders, including age, sex, years of education, handedness, total intracranial volume (ICV), and HC volume. RESULTS: The use of emotional support, venting, and positive reframing coping strategies were significantly and positively correlated with total, total right, and total left HC volumes. Venting was significantly associated with CA1 after adjusting for age, sex, handedness, and education (P=0.001, B = 0.265, P-FDR = 0.005). No significant association was observed between CERQ subscales and HC subfield volumes after controlling for confounders and multiple analyses. However, sensation-seeking subscale of the UPPS-P was positively correlated with total and right CA2-CA3 volumes after adjustments for age, sex, handedness, ICV, and HC volumes (P=0.002, B = 0.266, P-FDR = 0.035). BAS and BIS subscales did not show significant relationship with HC subfield volumes. CONCLUSION: Patterns of HC subfields volumes are associated with coping strategies, impulsivity, and emotion regulation. In particular, using emotional support, positive reframing, venting, and sensation seeking are significantly associated with certain HC subfield volumes. These findings suggest that the hippocampus may play a crucial role in modulating emotional responses and behavioral adaptations, offering potential targets for therapeutic interventions.

Reflection impulsivity in patients with panic disorder.

BACKGROUND: Individuals with panic disorder (PD) often exhibit a proclivity to conclude that an imminent catastrophe looms, drawing such conclusions from limited physical information. Reflection impulsivity, characterized by decision-making without adequate information, likely affects this bias. This study examines the relationship between reflection impulsivity and self-report impulsive features in individuals with PD. METHODS: Fifty patients with PD and 50 healthy controls (HC) participated to this study. Reflection impulsivity was assessed using the Information Sampling Task (IST), while trait impulsivity was measured using the Barratt Impulsiveness Scale (BIS). Participants also completed the Beck Anxiety Inventory, Panic and Agoraphobia Scale (P&A), and Anxiety Sensitivity Index-3 (ASI-3). RESULTS: Individuals with PD exhibited higher reflection impulsivity compared to HC. Increased reflection impulsivity correlated positively with PD severity as assessed by the P&A and cognitive concerns measured by ASI-3. No significant correlations were found with physical or social concerns. PD patients had higher BIS scores than HC. Higher trait impulsivity was linked to recurrent emergency department visits among PD patients. DISCUSSION: The findings of this study reveal the notion of increased impulsivity among individuals with PD and its relationship with cognitive concerns, as well as recurrent visits to the emergency department stemming from panic attacks.

Vitamin D Status and Behavioral Impulsivity in Anorexia Nervosa: Insights from a Longitudinal Study.

Anorexia nervosa (AN) is a severe psychiatric disorder marked by extreme weight control behaviors and significant impacts on physical and psychosocial health. This study explores the relationship between vitamin D (Vit-D) levels and impulsivity in women with AN. Forty-six cisgender White women participants were assessed upon admission and before discharge from a specialized eating disorder treatment center, with an average duration of 2.5 ± 0.10 months. Methods included self-reported questionnaires and behavioral tasks to measure impulsivity, alongside serum Vit-D levels. Our results showed significant improvements in Vit-D levels and certain impulsivity measures, such as faster reaction times and fewer errors on the go/no-go task, correlating with higher Vit-D levels. However, no significant correlations were found between Vit-D levels and self-reported impulsivity. These findings suggest that adequate Vit-D levels may enhance cognitive functions related to impulse control in AN. Given this study's limitations, including its exclusive focus on women and small sample size, future research should involve larger, more diverse populations and randomized clinical trials to better understand the causal relationships and therapeutic potential of Vit-D in managing AN-related impulsivity.

Trait impulsivity is associated with an increased risk of type 2 diabetes incidence in adults over 8 years of follow-up: results from the NutriNet-Santé cohort.

BACKGROUND: Type 2 diabetes is one of the most prevalent and preventable diseases worldwide and impulsivity, a psychological trait characterized by making quick decisions without forethought, has been suggested as a key feature for health-related conditions. However, there have been no studies examining the relationships between impulsivity and the incidence of type 2 diabetes and our aim was to assess the prospective association between trait impulsivity and the risk of developing type 2 diabetes. METHODS: A prospective observational study design was conducted between May 2014 and February 2023 within the NutriNet-Santé cohort. A web-based platform was used to collect data from the French adult population, with voluntary enrollment and participation. Of the 157,591 adults (≥ 18 years old) participating in the NutriNet-Santé study when impulsivity was assessed, 109,214 participants were excluded due to prevalent type 1 or 2 diabetes or missing data for impulsivity or follow-up data for type 2 diabetes. Trait impulsivity, and the attention, motor, and non-planning subfactors, were assessed at baseline using the Barratt Impulsiveness Scale 11. Incident type 2 diabetes was ascertained through follow-up. Medical information was reviewed by NutriNet-Santé physician experts to ascertain incident diabetes cases based on the ICD-10. Cox regression models, using hazard ratios and 95% confidence intervals (HR [95% CI]), were performed to evaluate associations between impulsivity per 1 standard deviation increment and type 2 diabetes risk, adjusting by recognized confounders. RESULTS: Of the 48,377 individuals studied (women 77.6%; age at baseline = 50.6 year ± 14.5 years), 556 individuals developed type 2 diabetes over a median follow-up of 7.78 (IQR: 3.97-8.49) years. Baseline impulsivity was associated with an increased risk of type 2 diabetes incidence (HR = 1.10 [1.02, 1.20]). The motor impulsivity subfactor was positively associated with type 2 diabetes risk (HR = 1.14 [1.04, 1.24]), whereas no associations were found for attention and non-planning impulsivity subfactors. CONCLUSIONS: Trait impulsivity was associated with an increased type 2 diabetes risk, mainly driven by the motor impulsivity subfactor. If these results are replicated in other populations and settings, trait impulsivity may become an important psychological risk factor to be considered in the prevention of type 2 diabetes. COHORT REGISTRATION: Name of registry: The NutriNet-Santé Study. A Web-based Prospective Cohort Study of the Relationship Between Nutrition and Health and of Dietary Patterns and Nutritional Status Predictors. Cohort registration number: NCT03335644. Date of registration: October 11, 2017. URL: https://clinicaltrials.gov/ct2/show/NCT03335644.

Impulsivity and self-harm behavior in patients with synthetic cannabinoids dependence.

BACKGROUND: Synthetic cannabinoids (SCs) dependence is increasingly prevalent among young individuals globally, with limited understanding of their potential detrimental effects. Therefore, we conducted this comparative study to assess impulsivity and non-suicidal self-harm behavior in patients with SCs dependence. SUBJECTS AND METHOD: We conducted this comparative, case-control study in the outpatient clinics of (Beni-suef University Hospital). We recruited 30 patients with SCs dependence and the 30 healthy subjects as a control group. Psychometric scales, including Addiction Severity Index (ASI), Barratt Impulsivity Scale-11 (BIS-11), Deliberate Self-harm Inventory-Short Version (DSHI), SCID I, SCID II, and drug urine screen, were applied to compare the two study arms. RESULTS: DSHI-s scores were significantly higher between the two study arms (3.23 ± 4.97 vs. 0.0 ± 0.0, p < 0.001, for cases and controls, respectively). Similarly, the mean ± SD score of the BIS scale was significantly higher in cases 68.13 ± 9.75 compared to the control group (45.67 ± 5.12) with a statistically significant difference (p < 0.001). Using the regression analysis, we observed a significant positive linkage between age, duration of substance use, DSHI-s, and the Barratt scale. CONCLUSION: Patients with synthetic cannabis addiction exhibited more impulsivity and self-harm behaviors compared to healthy controls. The adverse effects of substance use disorder escalated, notably in individuals classified as having severe addiction based on the Addiction Severity Index. Age and length of substance use were found to be potential factors influencing the level of impulsivity and self-harm actions.

Explaining child maltreatment and aggression among Chinese drug user: The mediating and moderating roles of drug craving and impulsivity.

BACKGROUND: The cycle of violence highlights a strong correlation between child maltreatment and aggression. However, there remains a significant gap in the pathway models of the cycle of violence. Given the exceptionally high rates of child maltreatment and violent crime among Chinese drug users, it is essential to examine the mechanisms of the cycle of violence within this group. OBJECTIVE: The current study incorporates drug craving and impulsivity into the child maltreatment-aggression mechanism. We explore the potential mediating and moderating roles of these variables and further examine the heterogeneity. PARTICIPANTS AND SETTING: A total of 894 participants (Meanage = 38.30, SDage = 8.38) were recruited as the final sample. METHODS: We employed moderated mediation and serial mediation models to explore the roles of drug craving and impulsivity. The Johnson-Neyman method was utilized to investigate moderating effects. Rich demographic variables and depression were controlled. RESULTS: There was no direct relationship between child maltreatment and aggression. The moderated mediation model indicated that drug craving played a mediating role, and there was a substitutive relationship between impulsivity and drug craving. The serial mediation model showed that child maltreatment could only affect drug craving (not impulsivity) and could ultimately influence aggression through a chain relationship. Heterogeneity tests revealed that the mechanisms might differ among various types of maltreatment. CONCLUSION: Drug craving holds a significant position in the cycle of violence. Compared to impulsivity, it is a more proximal factor to child mistreatment. Future research should also focus on the heterogeneity of child maltreatment for targeted interventions.

Causal computations of supplementary motor area on spatial impulsivity.

Spatial proximity to important stimuli often induces impulsive behaviour. How we overcome impulsive tendencies is what determines behaviour to be adaptive. Here, we used virtual reality to investigate whether the spatial proximity of stimuli is causally related to the supplementary motor area (SMA) functions. In two experiments, we set out to investigate these processes using a virtual environment that recreates close and distant spaces to test the causal contributions of the SMA in spatial impulsivity. In an online first experiment (N = 93) we validated and measured the influence of distant stimuli using a go/no-go task with close (21 cm) or distant stimuli (360 cm). In experiment 2 (N = 28), we applied transcranial static magnetic stimulation (tSMS) over the SMA (double-blind, crossover, sham-controlled design) to test its computations in controlling impulsive tendencies towards close vs distant stimuli. Reaction times and error rates (omission and commission) were analysed. In addition, the EZ Model parameters (a, v, Ter and MDT) were computed. Close stimuli elicited faster responses compared to distant stimuli but also exhibited higher error rates, specifically in commission errors (experiment 1). Real stimulation over SMA slowed response latencies (experiment 2), an effect mediated by an increase in decision thresholds (a). Current findings suggest that impulsivity might be modulated by spatial proximity, resulting in accelerated actions that may lead to an increase of inaccurate responses to nearby objects. Our study also provides a first starting point on the role of the SMA in regulating spatial impulsivity.

In Parkinson's disease dopaminergic medication and deep brain stimulation of the subthalamic nucleus increase motor, but not reflection and cognitive impulsivity.

Background: Parkinson's disease is associated with increased impulsivity, which can be divided into several domains: motor (consisting of proactive and reactive subdomains), reflection, and cognitive impulsivity. Evidence suggests that both dopaminergic medication and subthalamic nucleus deep brain stimulation can affect impulsivity. Therefore, we set out to investigate the effects of dopaminergic medication and subthalamic nucleus deep brain stimulation on motor, reflection, and cognitive impulsivity in Parkinson's disease patients. Methods: Twenty Parkinson's disease patients who underwent subthalamic nucleus deep brain stimulation were tested ON and OFF dopaminergic medication and ON and OFF subthalamic nucleus deep brain stimulation. They performed three different impulsivity tasks: the AX continuous performance task (AX-CPT) to test for motor impulsivity, the Beads task for reflection impulsivity, and the Delay discounting task for cognitive impulsivity. Results: The combination of subthalamic nucleus deep brain stimulation and dopaminergic medication led to an increase in motor impulsivity (p = 0.036), both proactive (p = 0.045) and reactive (p = 0.006). There was no effect of either dopaminergic medication or subthalamic nucleus deep brain stimulation on reflection and cognitive impulsivity. Conclusion: The combination of dopaminergic medication and subthalamic nucleus deep brain stimulation leads to increased motor, but not cognitive or reflection, impulsivity in patients with Parkinson's disease. Both proactive and reactive motor impulsivity were impaired by the combination of dopaminergic medication and subthalamic nucleus deep brain stimulation.