The frontal assessment battery (FAB) reveals neurocognitive dysfunction in substance-dependent individuals in distinct executive domains: Abstract reasoning, motor programming, and cognitive flexibility

Psychometric properties of the Spanish version of the Frontal Assessment Battery (FAB-E) and normative values in a representative adult population sample

BACKGROUND

The Frontal Assessment Battery is a short bedside test used to assess executive functions (EF). The aims of the present study were, first, to evaluate the psychometric proprieties of the Spanish version of the FAB (FAB-E) in a representative sample, and second, to establish cut-off points for impairment in executive function according to age and education level.

METHODS

A sample of 798 healthy Spanish adult subjects aged 19 to 91 participated in this study. Neuropsychological assessment of participants was conducted using the FAB-E, Mini-Mental State Examination (MMSE) and Trail Making Test (TMT). We examined internal consistency, intraclass correlation, test-retest reliability, and concurrent and divergent validity. In addition, we established a cut-off point for detecting executive function impairment based on the 5th percentile by age group and education level.

RESULTS

The analysis of the psychometric properties of the FAB-E showed good internal consistency (Cronbach's α = 0.60), intraclass correlation (0.72), test-retest reliability (0.70) and concurrent and divergent validity between the TMT (r = -0.523), MMSE (r = 0.426) and the FAB-E. The cut-off points for each age group were 16 points for the ≤ 29 group, 15 points for the 30-39 group, 14 points for the 40-49 and 50-59 groups, 12 points for the 60-69 group, and 10 points for the ≥ 70 age group.

CONCLUSIONS

The psychometric analysis showed that the FAB-E has good validity and reliability. Thus, FAB-E may be a helpful tool to evaluate EF in a healthy Spanish population. In addition, this study provides information on reference data that will be very valuable for clinicians and researchers.

Epidemiology of alcohol use disorder in the general population of Togo and Benin: the ALCOTRANS study

INTRODUCTION

Access to data concerning mental health, particularly alcohol use disorders (AUD), in sub-Saharan Africa is very limited. This study aimed to estimate AUD prevalence and identify the associated factors in Togo and Benin.

METHODS

A cross-sectional study was conducted between April and May 2022, targeting individuals aged 18 years and above in the Yoto commune of Togo and the Lalo commune of Benin. Subjects were recruited using a multi-stage random sampling technique. AUD diagnoses were made using the MINI adapted to DSM-5 criteria. Our study collected sociodemographic information, data on psychiatric comorbidities, stigmatization, and assessed cravings, using a series of scales. The association between AUD and various factors was analyzed using multivariable logistic regression.

RESULTS

In Togo, 55 of the 445 people investigated had AUD (12.4%; [95% CI: 9.5-15.7%]). Among them, 39 (70.9%) had severe AUD and the main associated comorbidities were suicidal risk (36.4%), and major depressive disorder (16.4%). Associated factors with AUD were male gender (aOR: 11.3; [95% CI: 4.8-26.7]), a higher Hamilton Depression Rating Scale (HDRS) score (aOR: 1.2; [95% CI: 1.1-1.3]) and a lower Stigma score measured by the Explanatory Model Interview Catalogue (EMIC) (aOR: 0.9; [95% CI: 0.8-0.9). The stigma scores reflect perceived societal stigma towards individuals with AUD. In Benin, 38 of the 435 people investigated had AUD (8.7%; [95% CI: 6.4-11.7]), and the main associated comorbidities were suicidal risk (18.4%), tobacco use disorder (13.2%) and major depressive episode (16.4%). Associated factors with AUD were male gender (aOR: 6.4; [95% CI: 2.4-17.0]), major depressive disorder (aOR: 21.0; [95% CI: 1.5-289.8]), suicidal risk (aOR: 3.7; [95% CI: 1.2-11.3]), a lower Frontal Assessment Battery (FAB) score (aOR:0.8; [95% CI: 0.8-0.9]) and a lower perceived stigma score (by EMIC )(aOR: 0.9; [95% CI: 0.8-0.9]).

CONCLUSION

In these communes of Togo and Benin, AUD prevalence is notably high. A deeper understanding of the disease and its local determinants, paired with effective prevention campaigns, could mitigate its impact on both countries.

The role of cognitive control and naming in aphasia

The classical aphasia literature has placed considerable emphasis on the language-centered understanding of aphasia and failed to consider the role of executive functions (EFs) regarding different aspects of patients' performance. Many current studies suggest deficits in EFs in individuals with aphasia, however, the available data is still limited. Here, our aim was to investigate the impairment of EFs and its potential negative effects on naming (slower performance, increased reaction time and/or decreased accuracy). We sought to determine whether the poor performance observed in word fluency task correlated with similar outcomes in naming. Our study involved five Hungarian post stroke aphasic patients (2 males and 3 females) between the ages of 60 and 70, as well as a control group matched for age and gender. The participants were diagnosed with different types of aphasia (global, Wernicke's, anomic and conduction). This study employed various neuropsychological and linguistic batteries. By comparing the patients' performance to that of the control group, we aimed to investigate the impacts of stroke. Within the aphasia group, we observed difficulties in following complex commands and a connection between general slowness and reduced accuracy in naming. We concluded that impairment of executive functions may have a negative impact on naming, comprehension, and fluency. Therefore, it is important to consider functional variations in neural networks, and to base our interpretations on the available psychophysiological data in literature. Our findings provide an alternative perspective to the traditional assessment of aphasia and highlight the importance of considering the role of executive functions.

Age-related differences in the effect of chronic alcohol on cognition and the brain: a systematic review

Adolescence is an important developmental period associated with increased risk for excessive alcohol use, but also high rates of recovery from alcohol use-related problems, suggesting potential resilience to long-term effects compared to adults. The aim of this systematic review is to evaluate the current evidence for a moderating role of age on the impact of chronic alcohol exposure on the brain and cognition. We searched Medline, PsycInfo, and Cochrane Library databases up to February 3, 2021. All human and animal studies that directly tested whether the relationship between chronic alcohol exposure and neurocognitive outcomes differs between adolescents and adults were included. Study characteristics and results of age-related analyses were extracted into reference tables and results were separately narratively synthesized for each cognitive and brain-related outcome. The evidence strength for age-related differences varies across outcomes. Human evidence is largely missing, but animal research provides limited but consistent evidence of heightened adolescent sensitivity to chronic alcohol's effects on several outcomes, including conditioned aversion, dopaminergic transmission in reward-related regions, neurodegeneration, and neurogenesis. At the same time, there is limited evidence for adolescent resilience to chronic alcohol-induced impairments in the domain of cognitive flexibility, warranting future studies investigating the potential mechanisms underlying adolescent risk and resilience to the effects of alcohol. The available evidence from mostly animal studies indicates adolescents are both more vulnerable and potentially more resilient to chronic alcohol effects on specific brain and cognitive outcomes. More human research directly comparing adolescents and adults is needed despite the methodological constraints. Parallel translational animal models can aid in the causal interpretation of observed effects. To improve their translational value, future animal studies should aim to use voluntary self-administration paradigms and incorporate individual differences and environmental context to better model human drinking behavior.

Screening Tools for Cognitive Impairment in Adults with Substance Use Disorders: A Systematic Review

OBJECTIVES

Cognitive impairment is common in individuals with substance use disorders (SUDs), yet no evidence-based guidelines exist regarding the most appropriate screening measure for use in this population. This systematic review aimed to (1) describe different cognitive screening measures used in adults with SUDs, (2) identify substance use populations and contexts these tools are utilised in, (3) review diagnostic accuracy of these screening measures versus an accepted objective reference standard, and (4) evaluate methodology of included studies for risk of bias.

METHODS

Online databases (PsycINFO, MEDLINE, Embase, and CINAHL) were searched for relevant studies according to pre-determined criteria, and risk of bias and applicability was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). At each review phase, dual screening, extraction, and quality ratings were performed.

RESULTS

Fourteen studies met inclusion, identifying 10 unique cognitive screening tools. The Montreal Cognitive Assessment (MoCA) was the most common, and two novel screening tools (Brief Evaluation of Alcohol-Related Neuropsychological Impairments [BEARNI] and Brief Executive Function Assessment Tool [BEAT]) were specifically developed for use within SUD populations. Twelve studies reported on classification accuracy and relevant psychometric parameters (e.g., sensitivity and specificity). While several tools yielded acceptable to outstanding classification accuracy, there was poor adherence to the Standards for Reporting Diagnostic Accuracy Studies (STARD) across all studies, with high or unclear risk of methodological bias.

CONCLUSIONS

While some screening tools exhibit promise for use within SUD populations, further evaluation with stronger methodological design and reporting is required. Clinical recommendations and future directions for research are discussed.

Standardization and diagnostic utility of the Frontal Assessment Battery for healthy people and patients with dementia in the Chilean population

The Frontal Assessment Battery (FAB) is a screening test that measures executive functions. Although this instrument has been validated in several countries, its diagnostic utility in a Chilean population has not been studied yet.

Objectives

This study aimed to (1) adapt FAB in a Chilean population; (2) study the psychometric properties of the FAB in a Chilean population; (3) assess the sociodemographic influence in the performance of the FAB in a sample of healthy controls (HC); and (4) develop normative data for this healthy group.

Methods

A HC (n=344) and a group of patients with dementia (n=156) were assessed with the Chilean version of FAB.

Results

FAB showed good internal consistency (Cronbach's alpha=0.79) and acceptable validity based on the relationship with other variables. Factor analysis showed the unidimensionality of the instrument. Significant differences were found in the total FAB value between the HC and dementia groups. With the matched sample, the established cutoff point was 13.5, showing a sensitivity of 80.8% and a specificity of 90.4%. Regression analysis showed that education and age significantly predicted FAB performance in the healthy group. Finally, normative data are provided.

Conclusions

This study shows that FAB is a useful tool to discriminate between healthy people and people with dementia. However, further studies are needed to explore the capacity of the instrument to characterize the dysexecutive syndrome in people with dementia in the Chilean population.

Relation of a Socioeconomic Index with Cognitive Function and Neuroimaging in Hypertensive Individuals

BACKGROUND

Socioeconomic factors are important contributors to brain health. However, data from developing countries (where social inequalities are the most prominent) are still scarce, particularly about hypertensive individuals.

OBJECTIVE

To evaluate the relationship between socioeconomic index, cognitive function, and cortical brain volume, as well as determine whether white matter hyperintensities are mediators of the association of the socioeconomic index with cognitive function in hypertensive individuals.

METHODS

We assessed 92 hypertensive participants (mean age = 58±8.6 years, 65.2%female). Cognitive evaluation and neuroimaging were performed and clinical and sociodemographic data were collected using questionnaires. A socioeconomic index was created using education, income, occupation (manual or non-manual work), and race. The associations of the socioeconomic index with cognitive performance and brain volume were investigated using linear regression models adjusted for age, sex, time of hypertension since diagnosis, and comorbidities. A causal mediation analysis was also conducted.

RESULTS

Better socioeconomic status was associated with better visuospatial ability, executive function, and global cognition. We found associations between a better socioeconomic index and a higher parietal lobe volume. White matter hyperintensities were also not mediators in the relationship between the socioeconomic index and cognitive performance.

CONCLUSION

Socioeconomic disadvantages are associated with worse cognitive performance and brain volume in individuals with hypertension.

Neurocognitive Changes in Spinocerebellar Ataxia Type 3: A Systematic Review with a Narrative Design

Spinocerebellar ataxia type 3 (SCA3), the commonest dominantly inherited ataxia worldwide, is characterized by disruption in the cerebellar-cerebral and striatal-cortical networks. Findings on SCA3-associated cognitive impairments are mixed. The classification models, tests and scoring systems used, language, culture, ataxia severity, and depressive symptoms are all potential confounders in neuropsychological assessments and may have contributed to the heterogeneity of the neurocognitive profile of SCA3. We conducted a systematic review of studies evaluating neurocognitive function in SCA3 patients. Of 1304 articles identified, 15 articles met the eligibility criteria. All articles were of excellent quality according to the National Institutes of Health quality assessment tool for case-control studies. In line with the disrupted cerebellar-cerebral and striatal-cortical networks in SCA3, this systematic review found that the neurocognitive profile of SCA3 is characterized by a core impairment of executive function that affects processes such as nonverbal reasoning, executive aspects of language, and recall. Conversely, neurocognitive domains such as general intelligence, verbal reasoning, semantic aspect of language, attention/processing speed, recognition, and visuospatial perception and construction are relatively preserved. This review highlights the importance of evaluating neurocognitive function in SCA3 patients. Considering the negative impact of cognitive and affective impairment on quality of life, this review points to the profound impairments that existing or future treatments should prioritize.

The Free-movement pattern Y-maze: A cross-species measure of working memory and executive function

Numerous neurodegenerative and psychiatric disorders are associated with deficits in executive functions such as working memory and cognitive flexibility. Progress in developing effective treatments for disorders may benefit from targeting these cognitive impairments, the success of which is predicated on the development of animal models with validated behavioural assays. Zebrafish offer a promising model for studying complex brain disorders, but tasks assessing executive function are lacking. The Free-movement pattern (FMP) Y-maze combines aspects of the common Y-maze assay, which exploits the inherent motivation of an organism to explore an unknown environment, with analysis based on a series of sequential two-choice discriminations. We validate the task as a measure of working memory and executive function by comparing task performance parameters in adult zebrafish treated with a range of glutamatergic, cholinergic and dopaminergic drugs known to impair working memory and cognitive flexibility. We demonstrate the cross-species validity of the task by assessing performance parameters in adapted versions of the task for mice and Drosophila, and finally a virtual version in humans, and identify remarkable commonalities between vertebrate species' navigation of the maze. Together, our results demonstrate that the FMP Y-maze is a sensitive assay for assessing working memory and cognitive flexibility across species from invertebrates to humans, providing a simple and widely applicable behavioural assay with exceptional translational relevance.

The Frontal Assessment Battery in RLS patients with and without augmentation

OBJECTIVE

We assessed frontal executive functions in patients with RLS/WED with and without augmentation and compared the results to healthy controls.

METHODS

We recruited 38 patients with RLS/WED. A total of 23 patients were treated with dopaminergic therapy and showed no signs of augmentation and 15 patients had a history of augmentation (AUG). Results were compared to 21 healthy controls. All individuals were assessed by the Frontal Assessment Battery (FAB) and the MMSE. Furthermore, impulsivity was assessed during a semi-structured interview.

RESULTS

Patients with AUG performed worse in the FAB than healthy controls and RLS/WED patients without AUG (p = 0.001, η² = 0.201). When we assessed the subtests of the FAB separately, we found a significant difference in the subtest assessing inhibitory control (p = 0.008, η² = 0.138).

CONCLUSIONS

Our findings suggest an impaired executive function in RLS/WED patients with augmentation compared to RLS/WED patients without augmentation and healthy controls. Long term neuroplastic changes within the prefrontal cortex may be the underlying cause for these results. However, further studies in a larger sample size and with a more extensive neuropsychological test battery are needed to confirm our preliminary results.

Neuroanatomical Differences Among Sexual Offenders: A Targeted Review with Limitations and Implications for Future Directions

As sexual assault and child sexual abuse continue to be worldwide public health concerns, research has continued to explore factors associated with sexual offending. Structural and functional neuroanatomical brain differences have been examined in an effort to differentiate sexual offenders and their behavior. This targeted review searched PubMed and Google Scholar for empirical studies using brain imaging techniques to examine possible structural or functional differences among control groups compared with at least one group of sexual offenders with contact offenses. This targeted review summarizes the structural and functional findings of 15 brain imaging studies (i.e., computed tomography, diffusion tensor imaging, magnetic resonance imaging, positron emission tomography, and functional magnetic resonance imaging), which suggest possible differences in brain size and gray matter volume, cortical thickness, white matter connectivity, and specific structural and functional differences among brain regions (fronto-temporal region, amygdala, prefrontal cortex, etc.). The methodological limitations of brain imaging studies and the associated findings with regard to sexual offenders are highlighted, as research indicates that many of the proposed differences in brain structure and function are not unique to this population. We further highlight several limitations to using neuroimaging studies to examine this population of interest, including publication bias, small sample size, underpowered studies, and all-male samples. As these results are mixed and findings are not seemingly unique to sexual offenders, we suggest future sexual offender research may benefit from focusing on more financially feasible options, such as neuropsychological assessment approaches, to assess for and attend to offenders' criminogenic and rehabilitative/therapeutic needs in alignment with the risk-need-responsivity model.

Value of the Frontal Assessment Battery Tool for Assessing the Frontal Lobe Function in Stroke Patients

OBJECTIVE

To examine the correlation between the Frontal Assessment Battery (FAB) test, which is used to assess the frontal lobe function, and anatomical lesions as well as the ability of the test to detect frontal lobe dysfunction.

METHODS

Records of stroke patients undergoing a FAB test and Mini-Mental State Examination (MMSE) were retrospectively reviewed. The patients were divided into three groups according to the lesions determined by an imaging study: frontal lobe cortex lesions, frontal subcortical circuit lesions, and other lesions. The FAB scores of the three groups were compared using the Kruskal-Wallis test. The validity of the FAB test to detect frontal lobe dysfunction was assessed by a comparison with the Computerized Neuropsychological Function Test (CNT) using the Spearman correlation coefficient. The correlation coefficients between the FAB test and MMSE were analyzed further based on the MMSE cutoff score.

RESULTS

Patients with frontal cortex lesions had significantly lower total and subtest scores according to the FAB test than the other patients. The FAB test correlated better with the CNT than the MMSE, particularly in the executive function and memory domains. A high MMSE score (r=0.435) indicated a lower correlation with the FAB test score than a low MMSE score (r=0.714).

CONCLUSION

The FAB test could differentiate frontal lobe lesions from others in stroke patients and showed a good correlation with the CNT. Moreover, the FAB test can be used in patients with high MMSE scores to detect frontal lobe dysfunction and determine the treatment strategies for stroke patients.

Trauma in childhood and adolescence and impaired executive functions are associated with uncertain reflective functioning in mothers with substance use disorder

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Uncertain reflective function in mothers with SUD are associated with trauma during childhood and adolescence.

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Impaired executive functions are significantly associated with uncertain reflective function.

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Certain reflective function is not associated with executive functions or trauma.

Aims

Impairments in reflective functioning are known to have adverse effects on the ability to display sensitive parenting as a caregiver. Several factors are associated with impairments in reflective functioning, such as impaired executive functioning and experienced trauma. We investigated how these factors contribute to an impaired reflective functioning style, such as pathological certain or uncertain reflective functioning. Extreme scores on these two subscales reflect two kinds of impairments in reflective functioning. We assessed executive functions, reflective functioning, and trauma in 43 mothers diagnosed with substance use disorders (SUD).

Methods

Certain or uncertain reflective functioning were assessed using the Reflective Functioning Questionnaire 8 (RFQ-8). Executive functions and trauma were assessed by administering various questionnaires, interviews and neuropsychological tests.

Results

High uncertain reflective functioning was more than six times as common (odds ratio) in mothers reporting high amounts of trauma in childhood and adolescence compared with mothers reporting low amounts of trauma. Impaired executive functions were also significantly associated with high uncertain reflective functioning. Certain reflective functioning did, however, not show any significant associations.

Conclusion

When the SUD mothers give information about relational trauma in childhood and adolescence, it might therefore be worth investigating and addressing the potential tendency to have an uncertain reflective functioning style.

Normative data for the Slovak version of the Frontal Assessment Battery (FAB)

The Frontal Assessment Battery (FAB) is a well-established screening measure of frontal lobe pathology. The aim of this study is the development of normative data for healthy Slovak adults. The final sample consisted of 487 healthy adults (54% of them female). The mean age in our sample was M = 55.29 (SD = 19.96). For the whole sample, the mean score on the FAB was 16.46 and the SD was 1.64. The mean score on the MMSE for the whole sample was 28.39 and the SD was 1.43. All participants underwent a complex neuropsychological examination spanning the relevant cognitive domains. FAB scores were found to be negatively associated with age (rs = -0.464, p < 0.001) and positively associated with years of education (rs = 0.199, p < 0.001). FAB scores positively correlated with the performance in MMSE (rs = 0.266, p < 0.001). Statistically significant and theoretically meaningful associations to other neuropsychological tests used in this study suggested the adequate convergent validity of the Slovak version of the FAB. The present study provided accurate normative FAB data, which can be used for clinical and research purposes.

Distinct effects of cocaine and cocaine + cannabis on neurocognitive functioning and abstinence: A six-month follow-up study

BACKGROUND AND AIMS

Cannabis use is frequent among individuals with cocaine use disorder. Despite recent non-controlled studies advocating a therapeutic role of smoked cannabis, there is a paucity of evidence-based data on potential therapeutic and cognitive side-effects of this association.

METHODS

We examined 63 cocaine-addicted subjects who used cannabis more than 50 times in lifetime (COC + CAN), 24 cocaine-addicted patients who use cannabis less than 50 times (COC), and 36 controls (CON). Participants were evaluated with an extensive battery of neurocognitive tests after two weeks of supervised detoxification in an inpatient treatment program. Patients were followed up in one, three, and six months after discharge.

RESULTS

Both groups of patients performed worse than CON on working memory, processing speed, inhibitory control, mental flexibility, and decision making. COC + CAN performed worse than COC on speed processing, inhibitory control and sustained attention, while COC performed worse than COC + CAN on mental flexibility. Concomitant cannabis use did not decrease relapses to cocaine use after one, three and six months. Among COC + CAN, earlier cocaine and cannabis use, and impaired executive functioning were predictive of relapse on cocaine after six months.

CONCLUSION

Our results did not support the recommendation of smoked cannabis as a safe therapeutic approach for cocaine-addicted patients due to significant negative cognitive side-effects and absence of efficacy. Further studies investigating frontal brain morphology, neuromaturation, and prescription of the non-psychoactive constituent of cannabis sativa cannabidiol among cocaine-addicted patients who use cannabis are warranted.

The association between executive functioning and parental stress and psychological distress is mediated by parental reflective functioning in mothers with substance use disorder

Mothers with a substance use disorder (SUD) have been found to exhibit heightened experience of stress and deficits in executive functioning (EF) and in parental reflective functioning (PRF). Although experiences of stress, EF and PRF are important for caregiving capacities; no studies have explored associations between the phenomena in mothers with SUD. This study aimed to examine the association between EF (working memory, inhibition, and cognitive flexibility) and different forms of stress (parental stress, general life stress, and psychological distress) in 43 mothers with SUD with infants. We further aimed to investigate whether PRF had a mediating function between EF and the experience of stress. The mothers completed self-report questionnaires regarding experiences of different types of stress, and we also used neuropsychological tests to assess EF and a semistructured interview to assess PRF. Results identified problems in EF were associated with higher parental stress and psychological distress but not with general life stress. Cognitive flexibility contributed uniquely to variance in parental stress, whereas working memory was a unique contributor to variance in psychological distress. PRF had a mediating function between EF and parental stress and between EF and psychological distress. Findings highlight the importance of considering individual differences in PRF when targeting EF in interventions trying to reduce the experience of parental stress and psychological distress in mothers with SUD.

Young frequent binge drinkers show no behavioral deficits in inhibitory control and cognitive flexibility

Alcohol intoxication and abuse are well-known to cause impairments in executive functioning and control. Still, we know surprisingly little about individuals engaging in frequent binge drinking, even though they have an increased risk to develop an alcohol use disorder (AUD) later in life. As this risk has been suggested to be linked to (premorbid) executive deficits, we assessed changes in cognitive flexibility and inhibition with the help of a switching task and a stop-change task. Both paradigms had previously been shown to be modulated by alcohol, as well as by functional variations in dopaminergic and GABAergic neurotransmission. We employed an extreme group approach, where we compared pre-selected samples of frequent binge drinkers and non-frequent binge drinkers, all of which had stably pursued their respective consumption pattern for at least 3 years. In combination with Bayes analyses, our results showed that individuals engaging in frequent binge drinking showed no impairments of cognitive flexibility or inhibition, as compared to non-frequent binge drinkers. These observations suggest that frequent binge drinking alone is not associated with the cognitive control deficits commonly observed in AUD. Importantly, the investigated executive functions are known to be altered both during binge drinking and in individuals with AUD. It could hence be speculated that their intermittent consumption pattern prevents non-AUD frequent binge drinkers from the homeostatic counter-regulations of alcohol- and control-associated neurotransmitter systems that may be observed in AUD patients. Yet, this hypothesis still needs to be tested in future research, including studies that combine MR and molecular imaging.

The role of neurocognitive functioning, substance use variables and the DSM-5 severity scale in cocaine relapse: A prospective study

BACKGROUND

The severity of substance use disorder (SUD) is currently defined by the sum of DSM-5 criteria. However, little is known about the validity of this framework or the role of additional severity indicators in relapse prediction. This study aimed to investigate the relationship between DSM-5 criteria, neurocognitive functioning, substance use variables and cocaine relapse among inpatients with cocaine use disorder (CUD).

METHODS

128 adults aged between 18 and 45 years were evaluated; 68 (59 males, 9 females) had CUD and 60 (52 males, 8 females) were healthy controls. For the group with CUD, the use of other substances was not an exclusion criterion. Participants were tested using a battery of neurocognitive tests. Cocaine relapse was evaluated 3 months after discharge.

RESULTS

Scores for attention span and working memory were worse in patients compared to controls. Earlier onset and duration of cocaine use were related to poorer inhibitory control and global executive functioning, respectively; recent use was related to worse performance in inhibitory control, attention span and working memory. More DSM-5 criteria at baseline were significantly associated with relapse.

CONCLUSIONS

Recent cocaine use was the most predictive variable for neurocognitive impairments, while DSM-5 criteria predicted cocaine relapse at three months post treatment. The integration of neurocognitive measures, DSM-5 criteria and cocaine use variables in CUD diagnosis could improve severity differentiation. Longitudinal studies using additional biomarkers are needed to disentangle the different roles of severity indicators in relapse prediction and to achieve more individualized and effective treatment strategies for these patients.

Vestibular dysfunction as cortical damage with amyotrophic lateral sclerosis

BACKGROUND

Cortical damage in areas such as the frontal lobe is reported in amyotrophic lateral sclerosis (ALS). However, aside from executive dysfunction, the pathological significance of this cortical damage has yet to be clarified. The present study investigated the effects of cortical damage on vestibular function in ALS.

METHODS

Subjects comprised 18 ALS patients and 18 age- and sex-matched healthy controls. Cold air caloric stimulation was performed in all subjects to induce vestibular nystagmus, which was analysed to evaluate vestibular function. Visual suppression testing to investigate the suppressive effects of visual stimuli on vestibular nystagmus was expressed as suppression rate (SR, %). Executive function was tested using the frontal assessment battery (FAB).

RESULTS

Suppression rate and FAB score were significantly lower in the ALS group than in the control group (p < 0.01 each). A positive correlation was also observed between SR and FAB score (R = 0.65, p = 0.023).

CONCLUSION

Visual suppression testing showed significant damage to the central nervous system vestibular control mechanisms, which utilize visual information in the ALS group and a positive correlation between SR and FAB score suggest a relationship between frontal lobe damage and impaired vestibular control. A simple vestibular function test may be useful as a tool to objectively monitor the progression of cerebral lesions in ALS.

Cognitive Control and Flexibility in the Context of Stress and Depressive Symptoms: The Cognitive Control and Flexibility Questionnaire

Cognitive control and (cognitive) flexibility play an important role in an individual's ability to adapt to continuously changing environments. In addition to facilitating goal-directed behaviors, cognitive control and flexibility have been implicated in emotion regulation, and disturbances of these abilities are present in mood and anxiety disorders. In the context of stressful experiences, the reported studies examined processes related to cognitive control and flexibility, emotional regulation and depressive symptoms. To this end, a brief (18-item) self-report measure - the Cognitive Control and Flexibility Questionnaire (CCFQ) - was developed. This questionnaire measures an individual's perceived ability to exert control over intrusive, unwanted (negative) thoughts and emotions, and their ability to flexibly cope with a stressful situation. In Study 1, the CCFQ was assessed among both university students (N = 300) and a community sample (N = 302). Preliminary analyses suggested a stable and reliable two-factor structure, that of cognitive control over emotion, and appraisal and coping flexibility. Scores on the CCFQ were strongly associated with greater depressive symptoms, even after controlling for other measures that had been taken to reflect cognitive control and (in)flexibility (e.g., the Ruminative Response Scale; Perseverative Thinking Questionnaire). In Study 2 (N = 368), lower scores on the CCFQ were related to more negative stressor appraisals (i.e., greater perceived threat and uncontrollability) of a personally meaningful stressful event. Perceptions of threat and uncontrollability, in turn, partially accounted for the association between CCFQ subscale scores and depressive symptoms. The relation between lower CCFQ scores and heightened depressive symptoms was also partially accounted for by less frequent engagement in problem-focused coping and more use of emotion-focused methods. In Study 3 (N = 47 females), lower scores on the cognitive control over emotion component of the CCFQ predicted elevated negative affect and an exacerbated cortisol response following an acute psychosocial stressor (Trier Social Stress Test). The present research points to the CCFQ as a useful self-report tool to identify ways through which cognitive control and flexibility might be manifested in stressful situations, and how reductions in flexibility might be accompanied by elevated symptoms of depression.

Prenatal and concurrent cocaine, alcohol, marijuana, and tobacco effects on adolescent cognition and attention

BACKGROUND

Prenatal cocaine/polydrug exposure (PCE) may increase vulnerability to substance use disorders due to associated cognitive deficits. We examined whether neurocognitive deficits in executive functions and attention observed in PCE children persisted to adolescence when compared to non-cocaine/polydrug (NCE) children, and whether adolescent substance use (tobacco, alcohol, marijuana) was also associated with neurocognitive deficits.

METHODS

354 (180 PCE, 174 NCE) adolescents in a longitudinal study from birth were administered the Wechsler Intelligence Scales for Children - IV (WISC-IV), and the Integrated Visual and Auditory Continuous Performance Test (IVA/CPT) at age 15.5. Assessments of prenatal exposure to cocaine, alcohol, marijuana, and tobacco and measures of use at age 15.5 were taken. Confounding factors measured included lead, the caregiving environment, and violence exposure. Relationships between drug use and prenatal exposures on outcomes were assessed through multiple regression.

RESULTS

Adolescents with PCE had deficits in Perceptual Reasoning IQ and visual attention. Prenatal alcohol exposure predicted verbal and working memory IQ and visual and auditory attention deficits. Adolescent tobacco, alcohol, and marijuana use predicted attention in addition to PCE, lead and the caregiving environment.

CONCLUSION

Prenatal cocaine and alcohol exposure and adolescent use of substances are associated with neurocognitive deficits known to increase vulnerability to SUDs.

The Experience of Patients with Alcohol Misuse after Surviving a Critical Illness. A Qualitative Study

RATIONALE

Alcohol misuse is common in patients admitted to the intensive care unit (ICU), but there is currently no evidence-based approach to address drinking in ICU survivors.

OBJECTIVES

We sought to describe the experience of ICU survivors with alcohol misuse during their hospitalization and the 3 months after hospital discharge to inform an alcohol-specific intervention for this unique population.

METHODS

We conducted a descriptive qualitative study of ICU survivors from medical ICUs in three separate hospitals with a positive screening result on the Alcohol Use Disorders Identification Test. Semistructured interviews were conducted 3 months after hospital discharge of patients. Patients were also allowed to nominate up to two friends or family members for enrollment to provide additional perspective on the patient's experience.

RESULTS

We enrolled 50 patients and 22 of their friends and/or family members. The average APACHE II score was 23, 80% of patients were male, and the average age was 50 years; 70% of patients and 77% of friends/family members completed the semistructured interview 3 months after hospital discharge. We identified three domains that could inform an alcohol-specific intervention, each with multiple themes: motivation with complications (anxiety and depression, critical illness as a catalyst, delirium and cognitive impairment); therapeutic alliance (autonomy, failure and opportunities to build a therapeutic alliance); and the return to the home milieu (lack of screening for depression and anxiety, social network support for drinking, social isolation, social network support for abstinence, lack of available and affordable treatment, and negative experiences with Alcoholics Anonymous).

CONCLUSIONS

An alcohol intervention for ICU survivors would account for the context in which patients are making a decision about their drinking and optimize the patient-provider interaction. Contrary to current paradigms that focus on addressing alcohol consumption only during a hospitalization, an intervention for ICU survivors should continue as patients transition from the hospital to home.

Sensitivity and specificity of Frontal Assessment Battery in newly diagnosed and untreated obstructive sleep apnea patients

BACKGROUND

Executive dysfunction (ED) is often observed in subjects diagnosed with obstructive sleep apnea (OSA), but their assessment requires facilities that are not always available. We aim to evaluate the extent to which Frontal Assessment Battery (FAB) discriminates ED in newly diagnosed, untreated, and without-comorbidity OSA patients.

METHODS

Sixty subjects participated in the study. Of these, 40 (31 males and 9 females) were newly diagnosed for OSA through full-night polysomnography (apnea/hypopnea index; M = 39.01, SD = 27.16), untreated, with a mean age of 54.50 years (SD = 8.90), while the remaining 20 (15 males and 5 females) had no symptoms of OSA (M = 51.60 years, SD = 10.70). The instruments used were the following: Questionnaire for Sleep Apnea Risk, Epworth Sleepiness Scale, Mini-Mental State Examination, and FAB.

RESULTS

The group with OSA exhibited significantly lower values in the FAB global score (p = 0.003) and in Conceptualization (p = 0.001) and Mental Flexibility (p = 0.009) subtests. ROC analysis showed adequate discriminative capacity for the FAB global score (AUC = 0.74) and for Conceptualization (AUC = 0.75) and Mental Flexibility (AUC = 0.70) scores.

CONCLUSIONS

The FAB is a short and no-time-consuming tool that can be used to investigate the presence of ED in untreated OSA patients with no comorbidities, providing clinicians with a simple and effective way of detecting the presence of this dysfunction and allowing a more informed decision for the need of a full neuropsychological assessment.

Distinct cognitive performance and patterns of drug use among early and late onset cocaine users

INTRODUCTION

Adolescence is a crucial period for neurodevelopment, but few studies have investigated the impact of early cocaine use on cognitive performance and patterns of substance use.

METHODS

We evaluated 103 cocaine dependent inpatients divided in two groups: early-onset users (EOG; n=52), late-onset users (LOG; n=51), and 63 healthy controls. Neuropsychological functioning was evaluated using Digits Forward (DF) and Backward (DB), Trail Making Test (TMT), Stroop Color Word Test (SCWT), Controlled Oral Word Association Test (COWAT), Wisconsin Card Sorting Test (WCST), Rey Osterrieth Complex Figure Test (ROCFT), Frontal Assessment Battery (FAB), and Iowa Gambling Test (IGT). Use of alcohol and other drugs was assessed with the Addiction Severity Index (ASI-6).

RESULTS

Analyses of covariance controlling for age, IQ and years of education showed that EOG presented worse performance in attention span (DF, p=0.020), working memory (DB, p=0.001), sustained attention (WCST, p=0.030), declarative memory (ROCFT, p=0.031) and general executive functioning (FAB, p=0.003) when compared with the control group. LOG presented impairments on divided attention (TMT, p=0.003) and general executive functioning (FAB, p=0.001) in relation to the control group. EOG presented higher use of cannabis and alcohol than LOG (p≤0.001).

CONCLUSION

Early-onset cocaine users display more pronounced neuropsychological alterations than controls, as well as a greater frequency of polydrug consumption than LOG. The prominent cognitive deficits in EOG probably reflect the deleterious interference of cocaine use with early stages of neurodevelopment. This may be related to more severe clinical characteristics of substance disorder in this subgroup, including polysubstance abuse.

Decreased subcortical volumes in alcohol dependent individuals: effect of polysubstance use disorder

Chronic alcohol use has widespread effects on brain morphometry. Alcohol dependent individuals are often diagnosed with comorbid substance use disorders. Alterations in brain morphometry may be different in individuals that are dependent on alcohol alone and individuals dependent on alcohol and other substances. We examined subcortical brain volumes in 37 individuals with alcohol dependence only (ADO), 37 individuals with polysubstance use disorder (PS) and 37 healthy control participants (HC). Participants underwent a structural MR scan and a model-based segmentation tool was used to measure the volume of 14 subcortical regions (bilateral thalamus, caudate, putamen, globus pallidus, hippocampus, amygdala and nucleus accumbens). Compared to HC, ADO had smaller volume in the bilateral hippocampus, right nucleus accumbens and right thalamus. PS only had volume reductions in the bilateral thalamus compared to HC. PS had a larger right caudate compared to ADO. Subcortical volume was negatively associated with drinking measures only in the ADO group. This study confirms the association between alcohol dependence and reductions in subcortical brain volume. It also suggests that polysubstance use interacts with alcohol use to produce limited subcortical volume reduction and at least one region of subcortical volume increase. These findings indicate that additional substance use may mask damage through inflammation or may function in a protective manner, shielding subcortical regions from alcohol-induced damage.

High IQ May "Mask" the Diagnosis of ADHD by Compensating for Deficits in Executive Functions in Treatment-Naïve Adults With ADHD

OBJECTIVE

To evaluate and compare the performance of adults with ADHD with high and standard IQ in executive functions (EF) tasks.

METHOD

We investigated the neuropsychological performance of 51 adults with ADHD, compared with 33 healthy controls (HC) while performing a wide battery of neuropsychological tests that measure executive functioning. Adults with clinical diagnosis of ADHD were divided into two groups according to their IQ level (IQ ≥ 110-ADHD group with more elevated IQ, and IQ < 110-ADHD group with standard IQ).

RESULTS

The ADHD group with standard IQ presented a worse executive functioning compared with the HC group in the following measures: Stroop 2 ( p = .000) and 3 ( p = .000), Trail Making Test (TMT) B ( p = .005), Wisconsin Card-Sorting Test (WCST)-perseverative errors ( p = .022) and failures to maintain set ( p = .020), Continuous Performance Test (CPT)-omission errors ( p = .005) and commission errors ( p = .000), and Frontal Assessment Battery (FAB)-conceptualization ( p = .016). The ADHD group with more elevated IQ presented only impairments in the CPT-commission errors ( p = .019) when compared with the control group.

CONCLUSION

Adults with ADHD and more elevated IQ show less evidence of executive functioning deficits compared with those with ADHD and standard IQ, suggesting that a higher degree of intellectual efficiency may compensate deficits in executive functions, leading to problems in establishing a precise clinical diagnosis.

Gambling Problems Among Community Cocaine Users

Cocaine use is highly prevalent and a major public health problem. While some studies have reported frequent comorbidity problems among cocaine users, few studies have included evaluation of gambling problems. This study aimed to estimate the prevalence of gambling problems and compare those who were at-risk gamblers with non-problem gamblers in terms of mental health problems, substance use problems, and some risk factors (i.e. family antecedents, erroneous perceptions and coping strategies) among individuals who smoke or inject cocaine. A total of 424 smoked or injected cocaine users recruited through community-based programs in Montreal (Quebec) completed the questionnaire, including the Canadian Pathological Gambling Index, the Composite International Diagnostic Interview, the CAGE, and the Severity Dependence Scale. Of the sample, 18.4 % were considered at-risk gamblers, of whom 7.8 % had problems gambling and 10.6 % were moderate-risk gamblers. The at-risk group was more likely to have experienced a recent phobic disorder and alcohol problems than the non-problem group. A multivariate analysis showed that, compared to those who were non-problem gamblers, the at-risk ones were more likely to have lost a large sum of money when they first started gambling, believed that their luck would turn, and gambled in reaction to painful life events. These results indicate the need to include routines for screening to identify gambling problem among cocaine users.

The Frontal Assessment Battery: Normative Performance in a Large Sample of Older Community-Dwelling Hospital Outpatient or General Practitioner Attenders

BACKGROUND

The Frontal Assessment Battery (FAB) is a short battery designed to assess frontal executive functioning, but data for interpretation of performance are limited.

OBJECTIVES

The Trinity, Ulster, Department of Agriculture (TUDA) study provided the opportunity to derive performance data from a large sample of community-dwelling hospital outpatient or general practitioner (GP) attenders.

METHODS

Normative analysis based on 2508 TUDA participants meeting these criteria: Mini-Mental State Examination (MMSE) >26/30, not depressed (Center for Epidemiologic Studies Depression <16) or anxious (Hospital Anxiety and Depression Scale <8), no history of stroke, or transient ischemic attack. Correlation and regression analyses were used to evaluate the effects of age, education, gender, and general cognition (MMSE). Norms for FAB were created stratified by age and education, using overlapping midpoint ranges of 10 years with a 3-year interval from age 60 to 97.

RESULTS

Age and education accounted for 9.6% of variance in FAB score ( r² = .096) with no significant effect of gender. The FAB and MMSE were modestly correlated ( r = .29, P < .01) with MMSE increasing the model's total explained variance in FAB score from 9.6% to 14%.

CONCLUSION

This is the largest study to date to create normative data for the FAB. Age and education had the most significant impact on FAB performance, which was largely independent of global cognition (MMSE). These data may be of benefit in interpreting FAB performance in individuals with similar demographic/health status characteristics in hospital outpatient or GP settings.

Differential roles of medial prefrontal subregions in the regulation of drug seeking

The prefrontal cortex plays an important role in shaping cognition and behavior. Many studies have shown that medial prefrontal cortex (mPFC) plays a key role in seeking, extinction, and reinstatement of cocaine seeking in rodent models of relapse. Subregions of mPFC appear to play distinct roles in these behaviors, such that the prelimbic cortex (PL) is proposed to drive cocaine seeking and the infralimbic cortex (IL) is proposed to suppress cocaine seeking after extinction. This dichotomy of mPFC function may be a general attribute, as similar dorsal-ventral distinctions exist for expression vs. extinction of fear conditioning. However, other results indicate that the role of mPFC neurons in reward processing is more complex than a simple PL-seek vs. IL-extinguish dichotomy. Both PL and IL have been shown to drive and inhibit drug seeking (and other types of behaviors) depending on a range of factors including the behavioral context, the drug-history of the animal, and the type of drug investigated. This heterogeneity of findings may reflect multiple subcircuits within each of these PFC areas supporting unique functions. It may also reflect the fact that the mPFC plays a multifaceted role in shaping cognition and behavior, including those overlapping with cocaine seeking and extinction. Here we discuss research leading to the hypothesis that dorsal and ventral mPFC differentially control drug seeking and extinction. We also present recent results calling the absolute nature of a PL vs. IL dichotomy into question. Finally, we consider alternate functions for mPFC that correspond less to response execution and inhibition and instead incorporate the complex cognitive behavior for which the mPFC is broadly appreciated.

Persistent effects of chronic Δ9-THC exposure on motor impulsivity in rats

RATIONALE

In humans, long-term marijuana use is associated with impaired impulse control and attentional capacity, though it has been difficult to distinguish pre-existing cognitive deficits from possible consequences of prolonged marijuana exposure.

OBJECTIVE

To evaluate the effects of long-term exposure to Δ9-Tetrahydrocannabinol (Δ9-THC), the primary psychoactive constituent in marijuana, on indices of impulse control and attentional capacity using the rat 5-Choice Serial Reaction Time Task (5-CSRTT).

METHODS

Ten 14-day cycles of Δ9-THC dosing and 5-CSRTT testing were employed, each comprised of 5-day Δ9-THC dosing (0.3 or 3 mg/kg b.i.d.) and 5-CSRTT testing during the 9 days of drug abstinence. Subsequent 5-CSRTT testing continued during 5 weeks of protracted abstinence.

RESULTS

Dose-dependent increases in motor impulsivity (premature responses) and behavioral disinhibition (perseverative responses) emerged following 5 cycles of Δ9-THC exposure that persisted for the remaining dosing and testing cycles. Δ9-THC-related disruptions in motor impulsivity and behavioral inhibition were most pronounced during cognitively challenging 5-CSRTT sessions incorporating varying novel inter-trial intervals (ITIs), and these disruptions persisted for at least 5 weeks of Δ9-THC abstinence. Δ9-THC-related impairments in attentional capacity (response accuracy) were also evident during variable ITI challenge tests, though these attentional disruptions abated within 3 weeks of Δ9-THC abstinence.

CONCLUSIONS

These observations demonstrate that long-term intermittent exposure to clinically meaningful Δ9-THC doses induces persistent impairments in impulse control and attentional function. If present in humans, these disruptions may impact academic and professional performance.

Compromised frontocerebellar circuitry contributes to nonplanning impulsivity in recovering alcoholics

RATIONALE

Degradation of frontocerebellar circuitry is a principal neural mechanism of alcoholism-related executive dysfunctions affecting impulse control and cognitive planning.

OBJECTIVE

We tested the hypothesis that alcoholic patients would demonstrate compromised dorsal anterior cingulate cortex (dACC) -cerebellar functional connectivity when adjusting their strategies to accommodate uncertain conditions and would recruit compensatory brain regions to overcome ineffective response patterns.

METHODS

Twenty-six alcoholics and 26 healthy participants underwent functional MRI in two sequential runs while performing a decision-making task. The first run required a response regardless of level of ambiguity of the stimuli; the second run allowed a PASS option (i.e., no response choice), which was useful on ambiguous trials.

RESULTS

Healthy controls demonstrated strong synchronous activity between the dACC and cerebellum while planning and executing a behavioral strategy. By contrast, alcoholics showed synchronous activity between the dACC and the premotor cortex, perhaps enabling successful compensation for accuracy and reaction time in certain conditions; however, a negative outcome of this strategy was rigidity in modifying response strategy to accommodate uncertain conditions. Compared with the alcoholic group, the control group had lower nonplanning impulsiveness, which correlated with using the option PASS to respond in uncertain conditions.

CONCLUSION

These findings suggest that compromised dACC-cerebellar functional circuitry contributes to recruitment of an alternative network-dACC-premotor cortex- to perform well under low-risk, unambiguous conditions. This compensatory network, however, was inadequate to enable the alcoholics to avert making poor choices in planning and executing an effective behavioral strategy in high-risk, uncertain conditions.

Motivational interviewing combined with chess accelerates improvement in executive functions in cocaine dependent patients: a one-month prospective study

BACKGROUND

In cocaine-dependent individuals, executive function (EF) deficits are associated with poor treatment outcomes. Psychological interventions and pharmacological approaches have produced only modest effect sizes. To date, studies of this topic have been few and limited. The aim of this study was to examine the effects of a new model of intervention, which integrates chess and Motivational Interviewing, Motivational Chess (MC) METHODS: We evaluated 46 cocaine-dependent inpatients (aged 18-45), in two groups-MC (n=26); and active comparison-AC (n=20). Using neuropsychological tests and an impulsivity scale, we assessed the subjects before and after the study period (one month of abstinence monitored by urine toxicology screening).

RESULTS

The MC and AC groups did not differ at baseline. In the post-intervention assessment (after one month), both groups showed significant improvements in attention, mental flexibility, inhibitory control, abstraction abilities, and decision-making (p<0.01). In addition, the improvement in working memory was more significant in the MC group than in the AC group (group-by-time interaction, p=01).

CONCLUSIONS

One month of abstinence was sufficient to improve various attentional and executive domains in cocaine-dependent subjects. The MC intervention was associated with greater improvements in EFs, especially working memory, suggesting that tailored interventions focusing on complex EFs accelerate the process of cognitive recovery during the initial period of abstinence.

Functional consequences of cocaine re-exposure after discontinuation of cocaine availability

Cocaine users exhibit a wide range of behavioral impairments accompanied by brain structural, neurochemical and functional abnormalities. Metabolic mapping studies in cocaine users and animal models have shown extensive functional alterations throughout the striatum, limbic system, and cortex. Few studies, however, have evaluated the persistence of these effects following cessation of cocaine availability. The purpose of this study, therefore, was to assess the functional effects of re-exposure to cocaine in nonhuman primates after the discontinuation of cocaine self-administration for 30 or 90 days, using the quantitative autoradiographic 2-[14C]deoxyglucose (2DG) method. Rhesus monkeys self-administered cocaine (fixed interval 3-min schedule, 30 infusions per session, 0.3 mg/kg/infusion) for 100 sessions followed by 30 (n=4) or 90 days (n=3) during which experimental sessions were not conducted. Food-reinforced control animals (n=5) underwent identical schedules of reinforcement. Animals were then re-exposed to cocaine or food for one final session and the 2DG method applied immediately after session completion. Compared to controls, re-exposure to cocaine after 30 or 90 day drug-free periods resulted in lower rates of glucose utilization in ventral and dorsal striatum, prefrontal and temporal cortex, limbic system, thalamus, and midbrain. These data demonstrate that vulnerability to the effects of cocaine persists for as long as 90 days after cessation of drug use. While there was some evidence for recovery (fewer brain areas were affected by cocaine re-exposure at 90 days as compared to 30 days), this was not uniform across regions, thus suggesting that recovery occurs at different rates in different brain systems.

Interindividual differences in cognitive flexibility: influence of gray matter volume, functional connectivity and trait impulsivity

Cognitive flexibility, a core aspect of executive functioning, is required for the speeded shifting between different tasks and sets. Using an interindividual differences approach, we examined whether cognitive flexibility, as assessed by the Delis-Kaplan card-sorting test, is associated with gray matter volume (GMV) and functional connectivity (FC) of regions of a core network of multiple cognitive demands as well as with different facets of trait impulsivity. The core multiple-demand network was derived from three large-scale neuroimaging meta-analyses and only included regions that showed consistent associations with sustained attention, working memory as well as inhibitory control. We tested to what extent self-reported impulsivity as well as GMV and resting-state FC in this core network predicted cognitive flexibility independently and incrementally. Our analyses revealed that card-sorting performance correlated positively with GMV of the right anterior insula, FC between bilateral anterior insula and midcingulate cortex/supplementary motor area as well as the impulsivity dimension "Premeditation." Importantly, GMV, FC and impulsivity together accounted for more variance of card-sorting performance than every parameter alone. Our results therefore indicate that various factors contribute individually to cognitive flexibility, underlining the need to search across multiple modalities when aiming to unveil the mechanisms behind executive functioning.

Shall we use non-verbal fluency in schizophrenia? A pilot study

Over the last few years, numerous studies have attempted to explain fluency impairments in people with schizophrenia, leading to heterogeneous results. This could notably be due to the fact that fluency is often used in its verbal form where semantic dimensions are implied. In order to gain an in-depth understanding of fluency deficits, a non-verbal fluency task - the Five-Point Test (5PT) - was proposed to 24 patients with schizophrenia and to 24 healthy subjects categorized in terms of age, gender and schooling. The 5PT involves producing as many abstract figures as possible within 1min by connecting points with straight lines. All subjects also completed the Frontal Assessment Battery (FAB) while those with schizophrenia were further assessed using the Positive and Negative Syndrome Scale (PANSS). Results show that the 5PT evaluation differentiates patients from healthy subjects with regard to the number of figures produced. Patients׳ results also suggest that the number of figures produced is linked to the "overall executive functioning" and to some inhibition components. Although this study is a first step in the non-verbal efficiency research field, we believe that experimental psychopathology could benefit from the investigations on non-verbal fluency.

Reasoning deficits among illicit drug users are associated with aspects of cannabis use

Deficits in deductive reasoning have been observed among ecstasy/polydrug users. The present study seeks to investigate dose-related effects of specific drugs and whether these vary with the cognitive demands of the task. One hundred and five participants (mean age 21.33, SD 3.14; 77 females, 28 males) attempted to generate solutions for eight one-model syllogisms and one syllogism for which there was no valid conclusion. All of the one-model syllogisms generated at least one valid conclusion and six generated two valid conclusions. In these six cases, one of the conclusions was classified as common and the other as non-common. The number of valid common inferences was negatively associated with the aspects of short-term cannabis use and with measures of IQ. The outcomes observed were more than simple post-intoxication effects since cannabis use in the 10 days immediately before testing was unrelated to reasoning performance. Following adjustment for multiple comparisons, the number of non-common valid inferences was not significantly associated with any of the drug-use measures. Recent cannabis use appears to impair the processes associated with generating valid common inferences while not affecting the production of non-common inferences. It is possible, therefore, that the two types of inference may recruit different executive resources, which may differ in their susceptibility to cannabis-related effects.

Characterization of electrically evoked field potentials in the medial prefrontal cortex and orbitofrontal cortex of the rat: modulation by monoamines

Medial prefrontal cortex (mPFC) and orbitofrontal cortex (OFC) play critical roles in cognition and behavioural control. Glutamatergic, GABAergic, and monoaminergic dysfunction in the prefrontal cortex has been hypothesised to underlie symptoms in neuropsychiatric disorders. Here we characterised electrically-evoked field potentials in the mPFC and OFC. Electrical stimulation evoked field potentials in layer V/VI of the mPFC and layer V of the OFC. The earliest component (approximately 2 ms latency) was insensitive to glutamate receptor blockade and was presumed to be presynaptic. Later components were blocked by 6,7-dinitroquinoxaline-2,3-dione (DNQX (20 µM)) and were assumed to reflect monosynaptic (latency 4-6 ms) and polysynaptic activity (latency 6-40 ms) mediated by glutamate via AMPA/kainate receptor. In the mPFC, but not the OFC, the monosynaptic component was also partly blocked by 2-amino-5-phosphonopentanoic acid (AP-5 (50-100µM)) indicating the involvement of NMDA receptors. Bicuculline (3-10 µM) enhanced the monosynaptic component suggesting electrically-evoked and/or glutamate induced GABA release inhibits the monosynaptic component via GABAA receptor activation. There were complex effects of bicuculline on polysynaptic components. In the mPFC both the mono- and polysynaptic components were attenuated by 5-HT (10-100 µM) and NA (30 and 60 µM) and the monosynaptic component was attenuated by DA (100 µM). In the OFC the mono- and polysynaptic components were also attenuated by 5-HT (100 µM), NA (10-100 µM) but DA (10-100 µM) had no effect. We propose that these pharmacologically characterised electrically-evoked field potentials in the mPFC and OFC are useful models for the study of prefrontal cortical physiology and pathophysiology.

Performance on the Frontal Assessment Battery is sensitive to frontal lobe damage in stroke patients

Background

The Frontal Assessment Battery (FAB) is a brief battery of six neuropsychological tasks designed to assess frontal lobe function at bedside [Neurology 55:1621-1626, 2000]. The six FAB tasks explore cognitive and behavioral domains that are thought to be under the control of the frontal lobes, most notably conceptualization and abstract reasoning, lexical verbal fluency and mental flexibility, motor programming and executive control of action, self-regulation and resistance to interference, inhibitory control, and environmental autonomy.

Methods

We examined the sensitivity of performance on the FAB to frontal lobe damage in right-hemisphere-damaged first-ever stroke patients based on voxel-based lesion-behavior mapping.

Results

Voxel-based lesion-behavior mapping of FAB performance revealed that the integrity of the right anterior insula (BA13) is crucial for the FAB global composite score, for the FAB conceptualization score, as well as for the FAB inhibitory control score. Furthermore, the FAB conceptualization and mental flexibility scores were sensitive to damage of the right middle frontal gyrus (MFG; BA9). Finally, the FAB inhibitory control score was sensitive to damage of the right inferior frontal gyrus (IFG; BA44/45).

Conclusions

These findings indicate that several FAB scores (including composite and item scores) provide valid measures of right hemispheric lateral frontal lobe dysfunction, specifically of focal lesions near the anterior insula, in the MFG and in the IFG.

Preliminary evidence for a sex-specific relationship between amount of cannabis use and neurocognitive performance in young adult cannabis users

Accumulating evidence suggests neuropsychological deficits from cannabis use, with a burgeoning area of preclinical research indicating possible sex-differences. However, few studies have examined how cannabis use may differentially impact neurocognition in male and female cannabis users. As such, we examined potential sex-differences in associations between amount of cannabis use (across several time frames) and neurocognitive performance among young adult regular cannabis users. Consistent with previous studies, more cannabis use was generally associated with poorer episodic memory and decision-making, but not other measures of inhibitory control. However, patterns of results suggested sex-specific dissociations. In particular, more cannabis use was more consistently associated with poorer episodic memory performance in females than males. Conversely, more cannabis use was associated with poorer decision-making performance for males, but not females. These results provide further evidence for residual cannabis-associated neurocognitive deficits and suggest the importance of examining the impact of cannabis on neurocognition separately for males and females.

Cannabis use, cognition and brain structure in first-episode psychosis

Cannabis use is highly prevalent worldwide and it is associated with psychosis, but its effects on brain structure and cognition are still controversial. The aim of this paper is to investigate cognitive functioning and brain structure in patients with their first episode of psychosis who used Cannabis. We examined gray matter and lateral ventricle volumes in 28 patients with first-episode psychosis and a history of Cannabis use, 78 patients without a history of Cannabis use and 80 healthy controls who had not used Cannabis. Cognition was assessed using forward and backwards digit span tests, from the Wechsler Memory Scale-Third Edition (WMS-III) and the Controlled Oral Word Association Test (COWAT). Patients with a history of Cannabis use had less brain abnormalities, characterized by gray matter and lateral ventricle volume preservation, as well as less attentional and executive impairments compared to patients without a history of Cannabis use. Cannabis-using patients who develop psychosis have less neurodevelopmental impairment and better cognitive reserve than other psychotic patients; perhaps reflecting different etiological processes.

Effects of cannabis on neurocognitive functioning: recent advances, neurodevelopmental influences, and sex differences

Decades of research have examined the effects of cannabis on neurocognition. Recent advances in this field provide us with a better understanding of how cannabis use influences neurocognition both acutely (during intoxication) and non-acutely (after acute effects subside). Evidence of problems with episodic memory is one of the most consistent findings reported; however, several other neurocognitive domains appear to be adversely affected by cannabis use under various conditions. There is significant variability in findings across studies, thus a discussion of potential moderators is increasingly relevant. The purpose of this review was to 1) provide an update on research of cannabis' acute and non-acute effects on neurocognition, with a focus on findings since 2007 and 2) suggest and discuss how neurodevelopmental issues and sex differences may influence cannabis effects on neurocognition. Finally we discuss how future investigations may lead to better understanding of the complex interplay among cannabis, stages of neurodevelopment, and sex on neurocognitive functioning.

FAB-D: German version of the Frontal Assessment Battery

Executive dysfunction (ED) is a frequent consequence of neurological disorders, such as stroke, trauma or dementia, but also appears in normal aging. We developed a German version of the Frontal Assessment Battery (FAB-D), a short test which has previously been developed (Dubois et al., Neurology 55:1621-1626, 2000) to detect ED during bedside screening. A sample of 401 cognitively intact subjects aged 50-95 was tested with the FAB-D and several neuropsychological tests tapping executive functions, memory and calculation abilities. Aim of the study was to receive normative data for different age and educational groups, and to learn which tests predict performance on the FAB-D. We found clear effects of age and education; furthermore, FAB-D performance was predicted by other tests of executive functioning, but also by calculation and memory abilities. The present study reports data of healthy individuals and may be useful for comparing patients' performance with a normative sample.