Poor Inhibitory Control Research Articles

Impact of behavioral inhibitory control and startle reactivity to uncertain threat on youth suicide risk.

Poor inhibitory control and exaggerated threat reactivity are two well-established risk factors for suicide. Theory suggests that these two factors may interact to influence suicide risk, although few studies have directly tested these relationships. In the present study, we examined the unique and interactive effects of inhibitory control (IC) and threat reactivity on self-reported suicide risk in a sample of 132 youth, ages 16-19. The stop signal task was used as a behavioral index of IC. Threat reactivity was captured using a modified version of the No-Predictable-Unpredictable threat paradigm that includes threat of predictable (P-) and unpredictable (U-) mild electrical shock. Startle eyeblink potentiation was measured throughout the task as an index of aversive responding. All participants completed a battery of well-validated self-report measures including current suicide risk. Hierarchical linear regression analyses controlling for age and sex revealed no main effects of IC or threat reactivity. However, there was a significant IC by reactivity to uncertain threat (U-threat) interaction. At lower levels of IC, greater startle reactivity to U-threat was associated with greater suicide risk. At higher levels of IC, there was no association between reactivity to U-threat and suicide risk. These results suggest that individual differences in IC and reactivity to U-threat interact to influence suicide cognitions, shedding light on potential subgroups of individuals who might be at elevated risk.

Developmental patterns of inhibition and fronto-basal-ganglia white matter organisation in healthy children and children with attention-deficit/hyperactivity disorder.

There is robust evidence implicating inhibitory deficits as a fundamental behavioural phenotype in children with attention-deficit/hyperactivity disorder (ADHD). However, prior studies have not directly investigated the role in which white matter properties within the fronto-basal-ganglia circuit may play in the development of inhibitory control deficits in this group. Combining recent advancements in brain-behavioural modelling, we mapped the development of stop-signal task (SST) performance and fronto-basal-ganglia maturation in a longitudinal sample of children aged 9-14 with and without ADHD. In a large sample of 135 ADHD and 138 non-ADHD children, we found that the ADHD group had poorer inhibitory control (i.e., longer stop-signal reaction times) across age compared to non-ADHD controls. When applying the novel parametric race model, this group effect was driven by higher within-subject variability (sigma) and higher number of extreme responses (tau) on stop trials. The ADHD group also displayed higher within-subject variability on correct responses to go stimuli. Moreover, we observed the ADHD group committing more task-based failures such as responding on stop trials (trigger failures) and omissions on go trials (go failures) compared to non-ADHD controls, suggesting the contribution of attentional lapses to poorer response inhibition performance. In contrast, longitudinal modelling of fixel-based analysis measures revealed no significant group differences in the maturation of fronto-basal-ganglia fibre cross-section in a subsample (74 ADHD and 73 non-ADHD children). Finally, brain-behavioural models revealed that age-related changes in fronto-basal-ganglia morphology (fibre cross-section) were significantly associated with reductions in the variability of the correct go-trial responses (sigma.true) and skew of the stop-trial distribution (tauS). However, this effect did not differ between ADHD and typically developing children. Overall, our findings support the growing consensus suggesting that attentional deficits subserve ADHD-related inhibitory dysfunction. Furthermore, we show novel evidence suggesting that while children with ADHD are consistently performing worse on the SST than their non-affected peers, they appear to have comparable rates of neurocognitive maturation across this period.

8372 Evidence of dACC Glutamate Modulation During Top-down Inhibitory Control Predicting Weight Loss Ability in Individuals with Obesity Using1H fMRS

Abstract Disclosure: J.M. Eichstaedt: None. R. Sochocki: None. D. Khatib: None. N. Miller: None. V.A. Diwadkar: None. P. Burghardt: None. A.E. Rothberg: None. J.A. Stanley: None. Poor weight loss maintenance (WLM) following dietary intervention has been associated with poor top-down inhibitory control. The neurobiological mechanisms are not fully understood; it is not clear if changes to inhibitory control are specific to the presence of appetitive food cues. The dorsal anterior cingulate cortex (dACC) is central to inhibitory control and can be conceptualized selectively withholding ‘prepotent’ motor responses. This is driven by highly integrated glutamatergic and GABAergic neurotransmission. Temporal changes in glutamate, reflecting shifts in glutamate neurotransmission, can be detected under distinct processes or task conditions using [1]H fMRS. We investigated differences in dACC glutamate under task conditions with or without inhibitory motor control, utilizing neutral Squares and Food/Non-food stimuli, and their association with weight loss. Data were acquired from 13 individuals with obesity following dietary intervention resulting in 10% weight loss (5F; mean age: 50.1±5.2yrs). A visually-guided motor tapping task was used requiring participants to respond to stimuli under two modes, “Non-Selective” (motor responses to 100% of trials) and “Selective” (withholding responses on 20% of trials - involving both motor control and inhibition), and under two stimuli types (Squares and appetitive Food/Non-Food cues). Glutamate modulation changes (relative to the total signal) were assessed across stimuli type (independent of task mode) using repeated measures generalizing estimating equations (GEE) approach (SAS GENMOD). The correlation between glutamate during the Selective mode with food/non-food stimuli and percentage of weight lost during the dietary intervention was also assessed. The stimuli model term was not significant (χ2=3.50, p=0.174), but post hoc analysis indicated significantly increased glutamate during the Squares (z=-1.99, p=0.046), but not the Food/Non-food (z=-1.39, p=0.163) relative to baseline. A trending correlation between decreasing dACC glutamate modulation (Selective mode, Food/Non-Food) and decreasing percentage of weight lost during the intervention was observed (R2=0.274, F(1,11)=4.15, p=0.07). This suggests that the presence of appetitive food cues leads to a non-significant change in the dACC glutamate modulation independent of inhibitory or motor alone responses. The potential correlation between dACC glutamate modulation and weight loss provides preliminary support that appetitive food cues influence inhibitory control and the extent of the influences may be related to one’s ability to maintain weight loss. These results could provide greater understanding of the neurobiological mechanisms underlying top-down inhibitory processes influenced by affect and difficulties with weight loss and maintenance, potentially fueling better treatment for successful long-term WLM in obesity. Presentation: 6/1/2024

Transcranial Magnetic Stimulation: A New Possibility in Obesity Treatment

Obesity is a major public health challenge and results from the complex interaction of many etiopathogenetic factors. However, food-related hedonic stimuli and poor inhibitory control often appear to be specific maintenance factors, and conventional treatments are sometimes ineffective. Transcranial magnetic stimulation is emerging as a promising treatment option. Targeting specific brain regions, such as the dorsolateral prefrontal cortex, was found to be effective in modulating acute food craving and improving cognitive control. This review traces the evolution and development of transcranial magnetic stimulation and presents the results of recent randomized clinical trials conducted in obese subjects. These suggest that repetitive transcranial magnetic stimulation and deep transcranial magnetic stimulation may be effective in reducing body weight, BMI and food cravings. The neural circuits involved and the underlying mechanisms of action of this neurostimulation technique are also reviewed. Finally, outstanding questions and future research directions are identified to further understand and develop this promising therapy.

Effects of Auditory and Visual White Noise on Oculomotor Inhibition in Children With Attention-Deficit/Hyperactivity Disorder: Protocol for a Crossover Study.

In attention-deficit/hyperactivity disorder (ADHD), poor inhibitory control is one of the main characteristics, with oculomotor inhibition impairments being considered a potential biomarker of the disorder. While auditory white noise has demonstrated the ability to enhance working memory in this group, visual white noise is still unexplored and so are the effects of both types of white noise stimulation on oculomotor inhibition. This crossover study aims to explore the impact of auditory and visual white noise on oculomotor inhibition in children with ADHD and typically developing (TD) children. The study will investigate the impact of different noise levels (25% and 50% visual, 78 dB auditory), and performance will be evaluated both with and without noise stimulation. We hypothesize that exposure to white noise will improve performance in children with ADHD and impair the performance for TD children. Memory-guided saccades and prolonged fixations, known for their sensitivity in detecting oculomotor disinhibition in ADHD, will be used to assess performance. Children diagnosed with ADHD, withdrawing from medication for 24 hours, and TD children without psychiatric disorders were recruited for the study. Data collection was initiated in October 2023 and ended in February 2024. A total of 97 participants were enrolled, and the first results are expected between September and November 2024. This study will examine whether cross-modal sensory stimulation can enhance executive function, specifically eye movement control, in children with ADHD. In addition, the study will explore potential differences between auditory and visual noise effects in both groups. Our goal is to identify implications for understanding how noise can be used to improve cognitive performance. ClinicalTrials.gov NCT06057441; https://clinicaltrials.gov/study/NCT06057441. DERR1-10.2196/56388.

Neural and behavioral markers of inhibitory control predict symptom improvement during internet-delivered cognitive behavioral therapy for depression

Poor inhibitory control contributes to deficits in emotion regulation, which are often targeted by treatments for major depressive disorder (MDD), including cognitive behavioral therapy (CBT). Brain regions that contribute to inhibitory control and emotion regulation overlap; thus, inhibitory control might relate to response to CBT. In this study, we examined whether baseline inhibitory control and resting state functional connectivity (rsFC) within overlapping emotion regulation-inhibitory control regions predicted treatment response to internet-based CBT (iCBT). Participants with MDD were randomly assigned to iCBT (N = 30) or a monitored attention control (MAC) condition (N = 30). Elastic net regression was used to predict post-treatment Patient Health Questionnaire-9 (PHQ-9) scores from baseline variables, including demographic variables, PHQ-9 scores, Flanker effects (interference, sequential dependency, post-error slowing), and rsFC between the dorsal anterior cingulate cortex, bilateral anterior insula (AI), and right temporoparietal junction (TPJ). Essential prognostic predictor variables retained in the elastic net regression included treatment group, gender, Flanker interference response time (RT), right AI-TPJ rsFC, and left AI-right AI rsFC. Prescriptive predictor variables retained included interactions between treatment group and baseline PHQ-9 scores, age, gender, Flanker RT, sequential dependency effects on accuracy, post-error accuracy, right AI-TPJ rsFC, and left AI-right AI rsFC. Inhibitory control and rsFC within inhibitory control-emotion regulation regions predicted reduced symptom severity following iCBT, and these effects were stronger in the iCBT group than in the MAC group. These findings contribute to a growing literature indicating that stronger inhibitory control at baseline predicts better outcomes to psychotherapy, including iCBT.

Executive functions and behavioral economic demand for cannabis among young adults: Indirect associations with cannabis consumption and cannabis use disorder.

Behavioral economic demand for cannabis is robustly associated with cannabis consumption and cannabis use disorder (CUD). However, few studies have examined the processes underlying individual differences in the relative valuation of cannabis (i.e., demand). This study examined associations between executive functions and cannabis demand among young adults who use cannabis. We also examined indirect associations of executive functions with cannabis consumption and CUD symptoms through cannabis demand. Young adults (N = 113; 58.4% female; mean age 22 years) completed a Marijuana Purchase Task. Participants also completed cognitive tasks assessing executive functions (set shifting, inhibitory control, working memory) and semistructured interviews assessing past 90-day cannabis consumption (number of grams used) and number of CUD symptoms. Poorer inhibitory control was significantly associated with greater Omax (peak expenditure on cannabis) and greater intensity (cannabis consumption at zero cost). Poorer working memory was significantly associated with lower elasticity (sensitivity of consumption to escalating cost). Lower inhibitory control was indirectly associated with greater cannabis consumption and CUD symptoms through greater Omax and intensity, and poorer working memory was indirectly associated with greater cannabis consumption and CUD symptoms through reduced elasticity. This study provides novel evidence that executive functions are associated with individual differences in cannabis demand. Moreover, these results suggest that cannabis demand could be a mechanism linking poorer executive functioning with heavier cannabis use and CUD, which should be confirmed in future longitudinal studies. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Is impulsivity related to attentional bias in cigarette smokers? An exploration across levels of nicotine dependency and deprivation.

Research has largely focused on how attentional bias to smoking-related cues and impulsivity independently influence the development and maintenance of cigarette smoking, with limited exploration of the relationship between these mechanisms. The current experiments systematically assessed relationships between multiple dimensions of impulsivity and attentional bias, at different stages of attention, in smokers varying in nicotine dependency and deprivation. Nonsmokers (NS; n = 26), light-satiated smokers (LS; n = 25), heavy-satiated smokers (HS; n = 23) and heavy 12-hour nicotine-deprived smokers (HD; n = 30) completed the Barratt Impulsivity Scale, delayed discounting task, stop-signal task, information sampling task and a visual dot-probe assessing initial orientation (200 ms) and sustained attention (2000 ms) toward smoking-related cues. Sustained attention to smoking-related cues was present in both HS and LS, while initial orientation bias was only evident in HS. HS and LS also had greater levels of trait motor and nonplanning impulsivity and heightened impulsive choice on the delay discounting task compared with NS, while heightened trait attentional impulsivity was only found in HS. In contrast, in HD, nicotine withdrawal was associated with no attentional bias but heightened reflection impulsivity, poorer inhibitory control and significantly lower levels of impulsive choice relative to satiated smokers. Trait and behavioral impulsivity were not related to the extent of attentional bias to smoking-related cues at any stage of attention, level of nicotine dependency or state of deprivation. Findings have both clinical and theoretical implications, highlighting the unique and independent roles impulsivity and attentional bias may play at different stages of the nicotine addiction cycle.

Neurocognitive Errors and Noncontact Anterior Cruciate Ligament Injuries in Professional Male Soccer Players.

Evidence is emerging that core neurocognitive functions such as working memory and inhibitory control (ie, motor-response and attentional inhibition) are linked to the anterior cruciate ligament (ACL) injury risk. Research has been conducted in laboratory settings, but the contribution of neurocognition to actual ACL injuries under real-world conditions is unknown. To describe the possible neurocognitive errors involved in noncontact ACL injury mechanisms. Case series. Soccer matches. A total of 47 professional male soccer players. Three independent reviewers evaluated 47 videos of players sustaining noncontact ACL injuries. Neurocognitive errors in inhibitory control were operationalized as follows: (1) motor-response inhibition was scored when a player demonstrated poor decision-making and approached the opponent with high speed that reduced the ability to stop or change the intended action and (2) an attentional error was scored when a player shifted his selective attention away from the relevant task to irrelevant stimuli. Of 47 noncontact ACL injuries, 26 (55%) were related to a pressing-type injury, 19 (73%) of which involved a deceiving action made by the opponent, suggesting poor inhibitory control of the defender. Of the remaining 21 noncontact ACL injuries (45%), 16 (76%) could be attributed to attentional errors. Agreement among the 3 raters was very good for all items except poor decision-making, which showed fair to good agreement (Fleiss κ = 0.71). Interrater reliability was excellent (intraclass correlation coefficient = 0.99-1.00). Errors in motor-response inhibitory control and attentional inhibition were common during noncontact ACL injury events in professional male soccer players. The interrater agreement in detecting neurocognitive errors in general was very good.

State rumination predicts inhibitory control failures and dysregulation of default, salience, and cognitive control networks in youth at risk of depressive relapse: Findings from the RuMeChange trial

BackgroundTrait rumination is a habitual response to negative experiences that can emerge during adolescence, increasing risk of depression. Trait rumination is correlated with poor inhibitory control (IC) and altered default mode network (DMN) and cognitive control network (CCN) engagement. Provoking state rumination in high ruminating youth permits investigation of rumination and IC at the neural level, highlighting potential treatment targets. MethodsFifty-three high-ruminating youth were cued with an unresolved goal that provoked state rumination, then completed a modified Sustained Attention to Response Task (SART) that measures IC (commissions on no-go trials) in a functional MRI study. Thought probes measured state rumination about that unresolved goal and task-focused thoughts during the SART. ResultsGreater state rumination during the SART was correlated with more IC failures. CCN engagement increased during rumination (relative to task-focus), including left dorsolateral prefrontal cortex and dorsal-medial prefrontal cortex. Relative to successful response suppression, DMN engagement increased during IC failures amongst individuals with higher state and trait rumination. Exploratory analyzes suggested more bothersome unresolved goals predicted higher left DLPFC activation during rumination. LimitationsThe correlational research design did not permit a direct contrast of causal accounts of the relationship between rumination and IC. ConclusionsState rumination was associated with impaired IC and disrupted modulation of DMN and CCN. Increased CCN engagement during rumination suggested effortful suppression of negative thoughts, and this was greater for more bothersome unresolved goals. Relative task disengagement was observed during rumination-related errors. DMN-CCN dysregulation in high-ruminating youth may be an important treatment target.

Plasma concentration of leptin is related to food addiction in gambling disorder: Clinical and neuropsychological implications.

Data implicate overlaps in neurobiological pathways involved in appetite regulation and addictive disorders. Despite different neuroendocrine measures having been associated with both gambling disorder (GD) and food addiction (FA), how appetite-regulating hormones may relate to the co-occurrence of both entities remain incompletely understood. To compare plasma concentrations of ghrelin, leptin, adiponectin, and liver-expressed antimicrobial peptide 2 (LEAP-2) between patients with GD, with and without FA, and to explore the association between circulating hormonal concentrations and neuropsychological and clinical features in individuals with GD and FA. The sample included 297 patients diagnosed with GD (93.6% males). None of the patients with GD had lifetime diagnosis of an eating disorder. FA was evaluated with the Yale Food Addiction Scale 2.0. All patients were assessed through a semi-structured clinical interview and a psychometric battery including neuropsychological tasks. Blood samples to measure hormonal variables and anthropometric variables were also collected. From the total sample, FA was observed in23 participants (FA+) (7.7% of the sample, 87% males). Whencompared participants with and without FA, those with FA+ presented both higher body mass index (BMI) (p < 0.001) andleptin concentrations, after adjusting for BMI (p = 0.013). In patients with FA, leptin concentrations positively correlated with impulsivity, poorer cognitive flexibility, and poorer inhibitory control. Other endocrine measures did not differ between groups. The present study implicates leptin in co-occurring GD and FA. Among these patients, leptin concentration has been associated with clinical and neuropsychological features, such as impulsivity and cognitive performance in certain domains.

Enhanced impulsivity, poorer planning and rigid patterns when drawing in substance use disorder: a preliminary study

Neuropsychological assessment has uncovered deficits in several executive functions in substance use disorder (SUD) individuals. Nevertheless, research has reported moderate ecological validity in current neuropsychological paradigms. In this regard, drawing is a well-known cross-cutting task that integrates complex cognitive and affective processes. Therefore, its potential for improving the ecological validity of neuropsychological assessments has been outlined. The aim of the present study was threefold. First, we analyzed the impulsivity and planning capacity of SUD individuals (n = 16) compared to controls (n = 15) through a self-reported questionnaire and a neuropsychological paradigm. Second, we explored the differences between groups in drawing variables by means of the diagnostic drawing series, a validated drawing paradigm. Finally, we examined the relationship between the neuropsychological markers and the drawing variables. Compared to controls, SUD individuals reported higher impulsivity scores and worse planning capacity. Regarding drawing variables, SUD participants needed more time to complete the artwork, occupied more space with a predominant color and reported a lower tendency to use warmer and cooler colors than controls. Additionally, across the whole sample, higher impulsivity and worse planning capacity were related to a greater use of a predominant color. Our findings suggest difficulties in functions related to inhibitory control, as well as an alternative drawing pattern in SUD individuals. Remarkably, poor inhibitory control was associated with less variability in drawing. Together, the present preliminary study seems to reinforces the use of drawing as a valid tool for adding both diagnostic and therapeutic information to classical neuropsychological paradigms.

Investigating the association between white matter fiber density in the superior longitudinal fasciculus and inhibitory control in groups at‐risk of Alzheimer’s disease

AbstractBackgroundAlzheimer’s disease (AD) is associated with poorer memory and reduced grey matter volume. Non‐amnestic cognition and white matter (WM) changes are an alternative line of enquiry and may reveal earlier changes. We investigated how inhibitory control relates to the superior longitudinal fasciculus (SLF) in groups at‐risk of AD.MethodParticipants (n = 229; aged &gt; 55 years) from the Dementia Prevention Research Clinic, New Zealand were classified as control (C; n = 35), subjective cognitive decline (SCD; n = 60), single‐domain amnestic MCI (aMCI; n = 55), multiple‐domain MCI (mMCI; n = 52), and AD (n = 27). Using diffusion MRI, we measured WM fiber density (FD), fiber cross‐section (FC), and fiber density cross‐section (FDC) in the SLF (SLF1, SLF2, SLF3 in each hemisphere, Figure 1). We also measured inhibition (Trail‐Making B, Stroop Inhibition, Switching, Hayling Incongruency), generativity (Letter Fluency, Category Fluency), and processing speed (Trail‐Making A, Stroop Color Naming, Word Reading).ResultMultivariate analyses showed impaired cognition across groups, with stronger impairments in inhibition (F(4, 206) = 5.41, p &lt; .001; Wilk’s Λ = 0.55, η2p = 0.12) than processing speed (F(4, 217) = 2.45, p = .001; Wilk’s Λ = 0.84, η2p = 0.04). Generativity was also impaired across groups (p &lt; .01). Significant variation in FD was found across groups in all SLF tracts, except for left SLF1 (Figure 2a). Between‐group differences (Figure 2c) included greater FD in C in the right SLF2 than mMCI (p = .04, d = 0.58), in the right SLF3 than SCD (p = .04, d = 0.57) and mMCI (p = .003, d = 0.77), and in the left SLF3 than SCD (p = .04, d = 0.65), mMCI (p = .01, d = 0.69), and AD (p = .02, d = 0.67). Two separate partial least‐squares analyses showed that poorer inhibition, but not processing speed, was associated with lower FD in the SLF (Figure 3).ConclusionOverall, we found that reduced FD in the SLF was associated with poorer inhibitory control in risk groups of AD. Therefore, WM alterations in the SLF may provide an early marker in AD.

Pretreatment cognitive performance is associated with differential self-harm outcomes in 6 v. 12-months of dialectical behavior therapy for borderline personality disorder.

Recent findings suggest that brief dialectical behavior therapy (DBT) for borderline personality disorder is effective for reducing self-harm, but it remains unknown which patients are likely to improve in brief v. 12 months of DBT. Research is needed to identify patient characteristics that moderate outcomes. Here, we characterized changes in cognition across brief DBT (DBT-6) v. a standard 12-month course (DBT-12) and examined whether cognition predicted self-harm outcomes in each arm. In this secondary analysis of 240 participants in the FASTER study (NCT02387736), cognitive measures were administered at pre-treatment, after 6 months, and at 12 months. Self-harm was assessed from pre-treatment to 2-year follow-up. Multilevel models characterized changes in cognition across treatment. Generalized estimating equations examined whether pre-treatment cognitive performance predicted self-harm outcomes in each arm. Cognitive performance improved in both arms after 6 months of treatment, with no between-arm differences at 12-months. Pre-treatment inhibitory control was associated with different self-harm outcomes in DBT-6 v. DBT-12. For participants with average inhibitory control, self-harm outcomes were significantly better when assigned to DBT-12, relative to DBT-6, at 9-18 months after initiating treatment. In contrast, participants with poor inhibitory control showed better self-harm outcomes when assigned to brief DBT-6 v. DBT-12, at 12-24 months after initiating treatment. This work represents an initial step toward an improved understanding of patient profiles that are best suited to briefer v. standard 12 months of DBT, but observed effects should be replicated in a waitlist-controlled study to confirm that they were treatment-specific.

A randomized trial of the effects of COMT inhibition on subjective response to alcohol: Moderation by baseline COMT activity and mediation of alcohol self-administration.

Poor inhibitory control and enhanced subjective response to alcohol are interrelated risk factors for alcohol use disorder (AUD) that share underlying neural substrates, including dopamine signaling in the right prefrontal cortex, a potential target for pharmacological intervention. Cortical dopamine inactivation is primarily regulated by catechol-O-methyltransferase (COMT), an enzyme with large variation in activity as a function of the COMT rs4680 (val158met) single nucleotide polymorphism. In a previous randomized, placebo-controlled trial of the COMT inhibitor tolcapone (200 mg TID) in non-treatment-seeking participants with AUD, we found that tolcapone, relative to placebo, reduced alcohol self-administration only among rs4680 val-allele homozygotes, whose COMT activity is higher than in met-allele carriers. We conducted secondary analyses of the effects of tolcapone and baseline COMT activity, as indexed by both rs4680 genotype and an enzymatic activity assay, on the subjective response to alcohol in a bar-laboratory paradigm among 60 participants in the previous trial. Tolcapone did not affect alcohol-induced stimulation or sedation more than placebo. However, baseline COMT activity moderated the effects of the drug on both outcomes, such that tolcapone-treated participants with higher baseline COMT activity had less stimulation (p = 0.008) and sedation (p = 0.053) than participants with lower baseline COMT activity and those treated with placebo. Additionally, alcohol-induced stimulation significantly mediated the interacting effects of baseline COMT activity and tolcapone on bar-laboratory self-administration. Tolcapone may reduce subjective response to alcohol more effectively among individuals with preexisting high COMT activity an effect that could account for the drug's reduction of alcohol consumption among these individuals.

The neuropsychological profile of work addiction

The objective of this study was to examine, for the first time, the neuropsychological aspects of work addiction, with a specific emphasis on the cognitive factors identified by theoretical models. While previous research has highlighted self-reported obsessiveness and impulsiveness in work addiction, this study sought to go beyond self-report measures by employing also neuropsychological reaction time tasks to assess executive functions. A total of 101 participants were categorized into two groups based on their Work Addiction Risk Test scores: a high-risk group (HWA; n = 39) and a low-risk group (LWA; n = 62) for work addiction. Executive functions were assessed using Go/No-Go, Digit Span, Counting Span, N-back, and Card Sorting Tasks. The findings revealed that the HWA group had poorer inhibitory control and achieved lower scores on the more complex working memory task involving updating (2-back). However, they exhibited unaltered cognitive flexibility and outperformed the LWA group on the 1-back task associated with maintenance and storage of information and sustained attention. Higher levels of impulsiveness and compulsiveness were observed in the HWA group, consistent with previous studies. These findings highlight the role of inhibition and working memory in work addiction, potentially contributing to challenges such as inefficient working strategies and impaired social functioning. This study offers valuable insights into the neurocognitive aspects of work addiction, deepening our understanding of this phenomenon.

Poor inhibitory control predicts sex-specific vulnerability to nicotine rewarding properties in mice.

The risk of becoming addicted to tobacco varies greatly from individual to individual, raising the possibility of behavioural biomarkers capable of predicting sensitivity to nicotine reward, a crucial step in the development of nicotine addiction. Amongst all of nicotine's pharmacological properties, one of central importance is theenhancement of cognitive performances, which depend on the balance between attentional processes and inhibitory control. However, whether the cognitive enhancement effects of nicotine are predictive of sensitivity to its rewarding properties is still unknown. Using male and female mice, we investigated whether the effects of nicotine on cognitive performances are predictive of sensitivity to the rewarding properties of nicotine and, if so, whether this relationship is sex dependent. Naïve male and female mice were first assessed for their performances in both baseline conditions and following nicotine injection (0.15 and 0.30mg/kg) in a cued-Fixed Consecutive Number task (FCNcue) measuring both optimal (attention) and premature (inhibitory control) responding. Next, all mice underwent nicotine-induced conditioned place preference (CPP) in order to evaluate inter-individual differences in response to nicotine reward (0.30mg/kg). Results showed that males and females benefited from the effect of nicotine as a cognitive enhancer in the FCNcue task. However, only those males displaying poor inhibitory control, namely high-impulsive animals, subsequently displayed sensitivity to nicotine reward. In females, sensitivity to nicotine reward was independent of FCNcue performances, in both basal and nicotine conditions. Thus, our study suggests that poor inhibitory control and its modulation by nicotine may be a behavioural biomarker for sensitivity to nicotine reward and consequent vulnerability to nicotine addiction in males but not females.

The Interplay between Socioeconomic Status, Parenting and Temperament Predicts Inhibitory Control at Two Years of Age.

This paper investigates the interplay between environmental factors (socioeconomic status (SES) and parenting) and temperament in the development of inhibitory control (IC) at 2 years of age. We administered to toddlers (n = 59) a delay of gratification task which measures IC in the context of self-regulation. Parents reported their toddlers' temperament, parenting strategies, and SES. We hypothesized that poorer IC would be associated with more reactive temperament, less effortful control, lower SES and inconsistent/coercive parenting practices. Finally, we explored the interaction between temperament, parenting and SES. We found that both coercive parenting and low-SES were negatively correlated to IC at the age of 2 years. Temperamental reactivity was unrelated to IC, whereas temperamental effortful control (EC) was positively associated with IC. Results revealed a moderation effect of EC on the influence of coercive parenting and SES in toddlers' IC. Toddlers from lower SES backgrounds and with lower EC were more affected by inconsistent/coercive parenting practices and showed the poorest IC. In contrast, toddlers exhibiting high and average levels of EC seemed to be protected from the detrimental effect of low-SES and inconsistent/coercive parenting on IC. These results suggest that strengthening toddlers' EC and improving parents' parenting skills might be especially relevant for the development of IC in the context of self-regulation, particularly by preventing self-regulatory problems in children from socioeconomically deprived environments. Future studies with larger samples, focusing on populations from severe socioeconomically deprived environments, or intervention studies will be needed in order to confirm and expand our findings.

Translational findings linking poor inhibitory control and heightened drug reward sensitivity.

Poor inhibitory control and heightened sensitivity to drug reward are two well-established risk factors for substance use disorders. Although these risk factors have traditionally been studied independently, there is reason to expect they may be related at the neurobiological level. Here, translational studies investigating the association between poor inhibition and greater drug reward sensitivity in both laboratory animals and humans are reviewed. Findings show that in animals, inhibitory deficits are associated with greater self-administration of cocaine, nicotine, 3,4-methylenedioxy-methamphetamine (MDMA), and alcohol, but not heroin. Likewise, in healthy human volunteers, poor inhibitory control and less brain engagement in right frontal regions during inhibition are associated with greater and more positive subjective responses to amphetamine and alcohol. The potential neurobiological mechanisms underlying this association are discussed, including the number or function of striatal dopamine D₂ receptors, as well as the implications of the findings and directions for future research. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Fluoride exposure during pregnancy from a community water supply is associated with executive function in preschool children: A prospective ecological cohort study

BackgroundOn May 19, 2011, Calgary, Canada stopped fluoridating its drinking water. This prospective ecological study examined if maternal exposure to fluoride during pregnancy from drinking water that was fluoridated at the recommended level of 0.7 mg/L was associated with children's intelligence and executive function at 3–5 years of age. MethodsParticipants were 616 maternal-child pairs enrolled in the Calgary cohort of the Alberta Pregnancy Outcomes and Nutrition (APrON) study between 2009 and 2012. Maternal-child pairs were classified as fully exposed to fluoridated drinking water throughout pregnancy (n = 295); exposed to fluoridated drinking water for at least part of the pregnancy plus an additional 90 days (n = 220); or not exposed to fluoridated drinking water during pregnancy plus the 90 days prior to pregnancy (n = 101). Children's Full Scale IQs were assessed using the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition: Canadian (WPPSI-IVCDN). Children's executive functions were also assessed: working memory (WPPSI-IVCDN Working Memory Index), inhibitory control (Gift Delay, NEPSY-II Statue subtest), and cognitive flexibility (Boy-Girl Stroop, Dimensional Change Card Sort (DCCS)). ResultsNo associations were found between exposure group and Full Scale IQ. However, compared to no exposure, full exposure to fluoridated drinking water throughout pregnancy was associated with poorer performance on the Gift Delay (B = 0.53, 95 % CI = 0.31, 0.93). Sex-specific analyses revealed that girls in the fully exposed (AOR = 0.30, 95 % CI = 0.13, 0.74) and partially exposed groups (AOR = 0.42, 95 % CI = 0.17, 1.01) performed more poorly than girls in the not exposed group. Sex effects were also found on the DCCS; girls in the fully exposed (AOR = 0.34, 95 % CI = 0.14, 0.88) and partially exposed groups (AOR = 0.29, 95 % CI = 0.12, 0.73) performed more poorly. ConclusionMaternal exposure to drinking water throughout pregnancy fluoridated at the level of 0.7 mg/L was associated with poorer inhibitory control and cognitive flexibility, particularly in girls, suggesting a possible need to reduce maternal fluoride exposure during pregnancy.