Dysfunctional decision-making in binge-eating disorder: A meta-analysis and systematic review

Binge-Eating Disorder (BED) involves anticipatory craving and urges, subjective loss-of-control during binge-eating episodes, and post-feeding psychological distress and guilt. Evidence indicates neurocognitive dysfunctions contribute to BED onset, maintenance, and treatment response. However, an integrated understanding of how cognitive processes underpin BED symptomology is lacking. We utilised a multi-stage decision-making model defining ten cognitive processes underpinning Preference Formation, Choice Implementation, Feedback Processing, and Flexibility/Shifting, to comprehensively review research published since 2013. We used preregistered PICOS criteria to assess 1966 articles identified from PubMed, PsycInfo, and Scopus database searches. This yielded 50 studies reporting behavioural cognitive tasks outcomes, comparing individuals with BED to controls with normal and higher weight. Meta-analyses revealed a unique profile of cognitive dysfunctions that spanned all decision-making stages. Significant deficits were evident in Uncertainty Evaluation, Attentional Inhibition, Choice Consistency, and Cognitive Flexibility/Set-shifting. We propose a novel model of dysfunctional decision-making processes in BED and describe their role in binge-eating behaviour. We further highlight the potential for cognitive interventions to target these processes and address the significant treatment gap in BED.

Sense of control, selective attention, cognitive inhibition, and psychosocial outcomes after Retraining and Control Therapy (ReACT) in pediatric functional seizures

BACKGROUND

Differences in sense of control, cognitive inhibition, and selective attention in pediatric functional seizures (FS) versus matched controls implicate these as potential novel treatment targets. Retraining and Control Therapy (ReACT), which targets these factors, has been shown in a randomized controlled trial to be effective in improving pediatric FS with 82% of patients having complete symptom remission at 60 days following treatment. However, post-intervention data on sense of control, cognitive inhibition, and selective attention are not yet available. In this study, we assess changes in these and other psychosocial factors after ReACT.

METHODS

Children with FS (N = 14, Mage = 15.00, 64.3% female, 64.3% White) completed 8 weeks of ReACT and reported FS frequency at pre and post-1 (7 days before and after ReACT). At pre, post-1, and post-2 (60 days after ReACT), all 14 children completed the Pediatric Quality of Life Inventory Generic Core Scales, Behavior Assessment System (BASC2), and Children's Somatic Symptoms Inventory-24 (CSSI-24), and 8 children completed a modified Stroop task with seizure symptoms condition in which participants are presented with a word and respond to the ink color (e.g., "unconscious" in red) to assess selective attention and cognitive inhibition. At pre and post-1, ten children completed the magic and turbulence task (MAT) which assesses sense of control via 3 conditions (magic, lag, turbulence). In this computer-based task, participants attempt to catch falling X's while avoiding falling O's while their control over the task is manipulated in different ways. ANCOVAs controlling for change in FS from pre- to post-1 compared Stroop reaction time (RT) across all time points and MAT conditions between pre and post-1. Correlations assessed the relationships between changes in Stroop and MAT performance and change in FS from pre- to post-1. Paired samples t-tests assessed changes in quality of life (QOL), somatic symptoms, and mood pre to post-2.

RESULTS

Awareness that control was manipulated in the turbulence condition of the MAT increased at post-1 vs. pre- (p = 0.02, η2 = 0.57). This change correlated with a reduction in FS frequency after ReACT (r = 0.84, p < 0.01). Reaction time significantly improved for the seizure symptoms Stroop condition at post-2 compared to pre- (p = 0.02, η2 = 0.50), while the congruent and incongruent conditions were not different across time points. Quality of life was significantly improved at post-2, but the improvement was not significant when controlling for change in FS. Somatic symptom measures were significantly lower at post-2 vs. pre (BASC2: t(12) = 2.25, p = 0.04; CSSI-24: t(11) = 4.17, p < 0.01). No differences were observed regarding mood.

CONCLUSION

Sense of control improved after ReACT, and this improvement was proportional to a decrease in FS, suggesting this as a possible mechanism by which ReACT treats pediatric FS. Selective attention and cognitive inhibition were significantly increased 60 days after ReACT. The lack of improvement in QOL after controlling for change in FS suggests QOL changes may be mediated by decreases in FS. ReACT also improved general somatic symptoms independent of FS changes.

Overlapping and unique brain responses to cognitive and response inhibition

Although cognitive inhibition and response inhibition fall under the umbrella term of inhibition, the question remains whether the two aspects of inhibition engage shared or distinct brain regions. The current study is one of the first to examine the neural underpinnings of cognitive inhibition (e.g. the Stroop incongruency effect) and response inhibition (e.g. "no-go" response) within a single task. Adult participants (n = 77) completed an adapted version of the Simon Task in a 3T MRI scanner. The results demonstrated that cognitive and response inhibition recruited a group of overlapping brain regions (inferior frontal cortex, inferior temporal lobe, precentral cortex, parietal cortex). However, a direct comparison of cognitive and response inhibition revealed that the two aspects of inhibition also engaged distinct, task-specific brain regions (voxel-wise FWE corrected p < 0.05). Cognitive inhibition was associated with increases in multiple brain regions within the prefrontal cortex. On the other hand, response inhibition was associated with increases in distinct regions of the prefrontal cortex, right superior parietal cortex, and inferior temporal lobe. Our findings advance the understanding of the brain basis of inhibition by suggesting that cognitive inhibition and response inhibition engage overlapping but distinct brain regions.

Emotional working memory training improves cognitive inhibitory abilities in individuals with borderline personality trait: A randomized parallel-group trial

BACKGROUND

Cognitive inhibition impairment is one of the causes of impulsive behaviors in individuals with borderline personality disorder (BPD). This study aimed to investigate the effect of emotional working memory training (EWMT) on cognitive inhibition in individuals with a clinically significant borderline personality trait.

METHODS

In a randomized, parallel-group trial, 40 individuals with borderline personality trait, were selected out of 1000 screened individuals and were randomly assigned to the experimental (N = 20) and waiting-list control (N = 20) groups based on the score on the Borderline Personality Scale and the follow-up Structured Clinical Interview for DSM-IV Personality Disorders. The experimental group underwent 10 sessions of EWMT and the control group did not receive any intervention (waiting list). Participants completed the Stroop Color and Word Test (SCWT) and Go/No-Go task Before and after the intervention.

RESULTS

EWMT significantly reduced reaction time of incongruent trials in the SCWT and commission errors in the Go/No-Go task after the intervention only in the experimental group. Furthermore, the interference score in SCWT and commission error rate at the post-intervention time were significantly lower for the experimental vs the waitlist group.

LIMITATIONS

The single-blind design and absence of follow-up measures.

CONCLUSIONS

EWMT can improve cognitive inhibition in individuals with borderline personality trait and could be used for therapeutic purposes of impulsivity behavior in BPD.

Inhibitory control in obsessive compulsive disorder: A systematic review and activation likelihood estimation meta-analysis of functional magnetic resonance imaging studies

BACKGROUND

Patients with obsessive compulsive disorder (OCD) often show deficits in inhibitory control, which may underlie poor control over obsessions and compulsions. Several functional magnetic resonance imaging (fMRI) experiments utilizing a variety of tasks have investigated the neural correlates of inhibitory control in OCD. Evidence from existing meta-analyses suggests aberrant activation of regions in fronto-striatal circuits during inhibitory control. However, new fMRI articles have since been published, and a more rigorous methodology for neuroimaging meta-analyses is now available.

OBJECTIVES

First, to reevaluate the evidence for abnormal brain activation during performance of inhibitory control tasks in OCD while adhering to current best practices for meta-analyses, and second, to extend previous findings by separately assessing different subprocesses of inhibitory control.

METHOD

We systematically searched Web of Knowledge, ScienceDirect, Scopus, PubMed and the functional BrainMap database for fMRI articles that compared activation during performance of inhibitory control tasks in patients with OCD and healthy control (HC) subjects. Thirty-five experiments from 21 articles met our criteria for inclusion. We first performed activation-likelihood-estimation meta-analyses to elucidate brain areas in which case-control activation differences converged across articles and tasks. We then aimed to extend previous work by separately evaluating experiments requiring inhibition of a prepotent response without execution of an alternative response (i.e., response inhibition) and experiments requiring inhibition of a prepotent response and execution of an alternative response (i.e., cognitive inhibition).

RESULTS

The 35 experiments included a total of 394 patients and 410 controls. We did not find evidence of abnormal brain activation in OCD during inhibitory control when pooling data from all experiments. Analysis restricted to cognitive inhibition experiments showed abnormal activation of the dorsal anterior cingulate cortex (dACC; P = .04, cluster-level familywise error-corrected, cluster volume of 824 mm³). We did not have sufficient data to evaluate response inhibition experiments separately.

CONCLUSION

Findings of abnormal brain activation in OCD from different inhibitory control tasks do not appear to converge on the same brain regions, but the dACC may be implicated in abnormal cognitive inhibition. Our findings highlight a need for experiments that specifically target subprocesses of inhibitory control to achieve a more differentiated understanding of the neural correlates for impaired inhibitory control in OCD.

Overweight and executive functions, psychological and behavioral profile of Spanish adolescents

The prevalence of overweight and obesity among children and adolescents has risen dramatically increasing a major risk factor for non-communicable diseases and cognitive dysfunctions. This study aimed to analyze differences in the executive function´s development between overweight and normal-weight adolescents. As a secondary objective, we aimed to assess differences in adolescents' psychological and behavioral profiles between groups. In order to achieve the study's aim, 105 adolescent students (17.61 ± 7.43 years) completed an online questionnaire that analyzed variables regarding their executive functions' processes, their psychological and physical health as well as lifestyle habits. Results showed that executive functions development is associated with adolescent weight. A higher range of weight presents a lower ability to assess abstract reasoning and to shift cognitive strategies. Nevertheless, no differences were found between groups in the capacity to hold information in mind nor the ability to control impulsive responses. Furthermore, groups showed differences in the number of meals and gastritis, but no significant differences have been found in lifestyle variables such as mobile usage, smoking, physical activity, and hours of sleep per day. The results from the present study could be used to implement multidisciplinary programs to develop healthier habits.

Feeling rushed? Perceived time pressure impacts executive function and stress

Executive function (EF) is critical to everyday life, but it can be undermined by adverse psychological states like stress and negative affect. For example, inadequate time to perform a task is a common stressor that can disrupt EF. Although the impact of actual time pressure on EF has been established, little is known about how self-generated, perceived time pressure (PTP) affects EF in the absence of objective time limits. We chose Eriksen’s Flanker task as an index of cognitive inhibition, a key component of EF, and we varied the interval between successive trials, the inter-trial interval (ITI), to proxy PTP. This manipulation strongly impacted task performance: shrinking the ITI to increase PTP diminished cognitive inhibition and increased both stress and negative affect. Subsequently lengthening the ITI to decrease PTP reversed nearly all of these effects, except stress, which persisted. Multilevel linear regression modeling revealed that ITI and stress predicted inhibition, and exploratory mediation modeling suggested that stress mediates the relationship between ITI and inhibition. These findings validate perceived time pressure as an empirical stressor and demonstrate EF’s sensitivity to changes in PTP.

Cognitive inhibition behavioral tasks in online and laboratory settings: Data from Stroop, SART and Eriksen Flanker tasks

The provided dataset represents the performance of adult individuals in three experimental tasks measuring cognitive inhibition: the Stroop task; the SART task and the Eriksen Flanker task. All tasks were initially completed in a web setting (online) by 485 individuals. Additionally, randomly selected participants completed all these tasks one more time (220 participants) or two more times (100 participants) during separate laboratory session(s) offline. The provided dataset contains data both from the offline and online experimental sessions. For the Stroop and Flanker tasks, we have provided data on mean reaction times for correct answers and the percent of correct answers for both congruent and incongruent trials. For the SART task, we have provided data on the number and the percent of commission and omission errors; the mean correct reaction times in “go” trials; the standard deviations of correct reaction times in “go” trials; the coefficients of variability for correct reaction times in “go” trials; the mean reaction times for successful “go” trials proceeding successful “no-go” trials; and the mean reaction times for correct “go” trials proceeding failed “no-go” trials. Data from both laboratory sessions contains information on the age and gender of participants. Additionally, we have provided the dates and hours of all experimental sessions. This dataset can potentially be reused for exploratory research on cognitive inhibition, i.e., the stability of individual cognitive inhibition capacity over time; intercorrelations of various inhibition task performance measures; individual differences in cognitive inhibition; or the influence of task setting (web vs laboratory) on inhibition performance measured in different settings (web vs laboratory).

Cognitive control inhibition networks in adulthood are impaired by early iron deficiency in infancy

Iron deficiency, a common form of micronutrient deficiency, primarily affects children and women. The principal cause of iron deficiency is undernutrition in low-income countries and malnutrition in middle to upper income regions. Iron is a key element for myelin production, neuronal metabolism, and dopamine functions. Iron deficiency in early life can alter brain development and exert long-lasting effects. Control inhibition is an executive function that involves several brain regions, including the prefrontal cortex and caudate and sub-thalamic nuclei. Dopamine is the prevalent neurotransmitter underlying cognitive inhibition. We followed cohort study participants who had iron deficiency anemia in infancy as well non-anemic controls. At 22 years of age, the participants were subjected to functional magnetic resonance imaging (fMRI) to evaluate the correlation between functional connectivity and performance on an inhibitory cognitive task (Go/No-Go). We hypothesized that former iron deficient anemic (FIDA) participants demonstrate less strength in functional connectivity compared with controls (C). There were not significant group differences in the behavioral results in terms of accuracy and response time. A continuous covariate interaction analysis of functional connectivity and the Go/No-Go scores demonstrated significant differences between the FIDA and C groups. The FIDA participants demonstrated less strength in connectivity in brain regions related to control inhibition, including the medial temporal lobe, impairment in the integration of the default mode network (indicating decreased attention and alertness), and an increase in connectivity in posterior brain areas, all of which suggest slower circuitry maturation. The results support the hypothesis that FIDA young adults show differences in the connectivity of networks related to executive functions. These differences could increase their vulnerability to develop cognitive dysfunctions or mental disorders in adulthood.

Sense of control, selective attention and cognitive inhibition in pediatric functional seizures: A prospective case-control study

PURPOSE

To date, laboratory-based experimental behavioral methods have not been used to identify factors associated with pediatric functional seizures (FS), leaving a critical gap for effective treatment development.

METHODS

Children ages 13-18 with video-EEG-confirmed FS were matched to controls (MCs) based on income, sex, race, and age. A modified Stroop task which included a condition requiring participants to report the ink colors in which seizure symptom words were written (e.g., "shaking" in blue) measured selective attention and cognitive inhibition through response time. The magic and turbulence task assessed sense of control in three conditions (magic, lag, turbulence). Children with FS were asked to report premonitory symptoms predicting FS.

RESULTS

Participants included 26 children with FS and 26 MCs (Meanage=15.2, 74% female, 59% white). On Stroop, children with FS had a slower reaction time (Mean=1193.83) than MCs (Mean=949.26, p = 0.022) for seizure symptom words. Children with FS had significantly poorer sense of control in the turbulence condition of the magic and turbulence task (Mean=-3.99, SD=8.83) than MCs (Mean=-11.51, SD=7.87; t(20)=-2.61, p =0.017). Children with FS (Mean=-1.80, SD=6.54) also had significantly poorer sense of control in the magic condition than MCs (Mean=-5.57, SD=6.01; p =0.028). Ninety-eight percent of patients endorsed premonitory symptoms.

CONCLUSION

Compared with MCs, children with FS have (1) poorer selective attention and cognitive inhibition when presented with seizure-related information and (2) lower sense of control (i.e. poorer awareness that their control was manipulated). Premonitory symptoms were common. Sense of control, selective attention, and inhibition may be novel treatment targets for FS intervention.

Is Splitting Related to Resistance to Proactive Interference? A Process-Oriented Study of Kernberg's Conceptualization of Splitting

INTRODUCTION

Splitting, as a defense mechanism in Kernberg's theory, plays a significant role in the development and maintenance of polarized and oscillating representations of self/other characteristics of borderline personality disorder (BPD). Although the notion of splitting can be considered from a structural and a functional point of view, almost all empirical studies to date have focused on the former elements to the detriment of related cognitive processes.

METHODS

To further investigate the cognitive processes related to splitting, 60 participants were administered the Splitting Index and indexes of resistance to proactive interference (PI) using the interpersonal recent negative task with words that reflect negative or positive interactions compared to neutral words.

RESULTS

The use of splitting was uniquely and significantly predicted by a higher capacity to resist PI and a lower capacity to consistently maintain this resistance when presented with negative words, above and beyond BPD traits, primitive defenses, and the presentation of neutral words. Results showed no evidence of a relationship between splitting and resistance to PI with positive words.

CONCLUSION

Results appear compatible with Kernberg's conceptualization of splitting as an active defense process that relates to an unstable capacity to inhibit negative representations of the object from entering working memory.

The discrepant effect of acute stress on cognitive inhibition and response inhibition

This study aimed to investigate how acute stress impinges on individual's cognitive inhibition and response inhibition abilities. Electroencephalography was adopted when 35 healthy adult females performing the No Go Flanker task before and after the Trier Social Stress Test. Both inhibition processes evoked N2 and P3 components, but only the response inhibition evoked the late positive potential (LPP), indicating the response inhibition needed continuous cognitive effort to inhibit the prepotent response. The N2 and the P3 amplitudes were decreased, while the LPP amplitudes were increased under acute stress. These results suggested that acute stress caused the detrimental effect by occupying cognitive resources. Contrastingly, individuals actively regulated and made more efforts to counteract the detrimental effect of acute stress on response inhibition. Thus, acute stress impaired cognitive inhibition but did not affect response inhibition.

Cumulative Cardiovascular Disease Risk and Triglycerides Differentially Relate to Subdomains of Executive Function in Bipolar Disorder; preliminary findings

OBJECTIVES

Cardiovascular disease is disproportionally prevalent in bipolar disorder (BD) and has been linked to cognition in preliminary studies. Herein we evaluate the association between known risk factors for cardiovascular disease and executive function in BD patients compared to healthy controls.

METHODS

In a sample of n=57 individuals (n=23 BD, n=34 controls) we assessed two subdomains of executive function; cognitive flexibility (using the Trail Making Test - Part B) and cognitive inhibition (using the Stroop Colour Word Interference Task). Cardiovascular risk was assessed by means of serum triglyceride levels, body mass index (BMI) and waist circumference, as well as dietary saturated fat intake and a sex-specific cumulative cardiovascular risk score calculated using the Framingham Heart Study method.

RESULTS

Patients with BD had higher BMI and waist circumference, with more BD patients categorized as having central obesity than controls. In the BD group only, higher triglyceride levels were associated with worse cognitive flexibility, and elevated cumulative cardiovascular disease risk was associated with worse cognitive inhibition. No correlations between cardiovascular risk factors and executive function were evident in the control group.

LIMITATIONS

The study was limited by the small sample size and should be considered hypothesis-generating CONCLUSIONS: The associations between triglyceride levels, cumulative cardiovascular disease risk and executive functioning evident in BD in this study preliminarily indicate the potential for mechanistic overlap of physical health and cognitive function in the disorder.

Poor inhibition of personally-relevant facial expressions of sadness and anger predicts an elevated cortisol response following awakening six months later

Failure to inhibit interference from distracting emotional stimuli may obstruct an individual's ability to regulate their behavioural and emotional responses to environmental stressors. Few studies have examined the longitudinal association between cognitive inhibition and regulation of the hypothalamic-pituitary-adrenal axis (HPA) in the natural environment. Seventy-nine healthy adults underwent two assessments 6 months apart. Participants' ability to suppress interference from distracting emotional stimuli was assessed using a negative affective priming task that included both generic and personally-relevant (i.e., participants' intimate partners) facial expressions of emotion. Poorer inhibition of personally-relevant sad and angry faces, but not generic stimuli, significantly predicted an increased cortisol awakening response (CAR) six months later. Moreover, poor inhibition of personally-relevant sad faces mediated the relation between chronic stress and an elevated CAR. Difficulties inhibiting personally-relevant emotional information may represent a key mechanism in understanding how environmental stress influences HPA functioning.

Cognitive inhibition and attentional biases in the affective go/no-go performance of depressed, suicidal populations

BACKGROUND

Although cognitive inhibition deficits and attentional biases have been associated with suicidality, these findings have not been consistently reported across samples. The aim of the current study was to further investigate these variables among participants with differing suicidal risk.

METHODS

We compared affective go/no-go performance in 100 depressed individuals with both current suicidal ideation and a prior history of attempted suicide, 100 depressed individuals with current suicidal ideation, but no history of attempted suicide, 100 suicide attempters without current depression or suicidal ideation, and 100 healthy controls.

RESULTS

Suicide ideators with a history of attempted suicide committed more commission errors during negative word trials than any other group. Additionally, suicide ideators with no attempt history made more commission errors than did controls and previous attempters. An interaction for group status and emotional word valence revealed that suicide ideators with a history of attempted suicide responded fastest to negative words and slowest to positive words. Suicide ideators without an attempt history displayed a similar, but less pronounced pattern. Whereas, controls and previous attempters responded more quickly to positively valenced words.

LIMITATIONS

The use of cross-sectional self-report data and inclusion of only female participants limits generalizability.

CONCLUSIONS

Cognitive dysfunctions were apparent in all suicide vulnerable subjects, but significantly greater in suicide ideators with a history of attempted suicide. Suicidal ideation may be associated with a processing bias and inhibitory deficit for negative, mood-congruent information. These findings increase our knowledge of cognitive impairment in suicidality and may potentially help improve intervention strategies.

Impulsivity in the self-harm and suicidal behavior of young people: A systematic review and meta-analysis

BACKGROUND

Impulsivity is considered a possible phenotype underlying the expression of self-harm and suicidal behaviors. Yet impulsivity is a not a unitary construct and there is evidence that different facets of impulsivity follow different neurodevelopmental trajectories and that some facets may be more strongly associated with such behaviors than others. Moreover, it is unclear whether impulsivity is a useful predictor of self-harm or suicidal behavior in young people, a population already considered to display heightened impulsive behavior.

METHODS

A systematic review and meta-analysis of studies published in Medline, PubMed, PsychInfo or Embase between 1970 and 2017 that used a neurocognitive measure to assess the independent variable of impulsivity and the dependent variable of self-harm and/or suicidal behavior among young people (mean age < 30 years old).

RESULTS

6183 titles were identified, 141 full texts were reviewed, and 18 studies were included, with 902 young people with a self-harm or suicidal behavior and 1591 controls without a history of these behaviors. Deficits in inhibitory control (13 studies, SMD 0.21, p-value = 0.002, 95% confidence interval (CI) (0.08-0.34), prediction interval (PI) = 0.06-0.35) and impulsive decision-making (14 studies, SMD 0.17, p-value = 0.008, 95% CI (0.045-0.3), PI = 0.03-0.31) were associated with self-harm or suicidal behavior. There were no significant differences between measures of different facets of impulsivity (ie. delay discounting, risky decision-making, cognitive or response inhibition) and self-harm or suicidal behavior.

CONCLUSION

Multiple facets of impulsivity are associated with suicidal behavior in young people. Future suicide research should be designed to capture impulsive states and investigate the impact on different subtypes of impulsivity.

Testing the role of cognitive inhibition in physical endurance using high-definition transcranial direct current stimulation over the prefrontal cortex

The aim of this study was to clarify the role of the prefrontal cortex (PFC) in physical effort regulation. We hypothesized that the PFC would be progressively involved in physical endurance through the engagement of cognitive inhibition, which would be necessary to maintain effort by inhibiting fatigue-related cues. This hypothesis was examined using a double-blind, sham-controlled, within-subjects study (N = 20) using high-definition (HD) transcranial direct current stimulation (tDCS) over the right dorsolateral prefrontal cortex (dlPFC). Participants had to maintain a knee extensor contraction at 30% of their maximal force while simultaneously performing an Eriksen flanker task to evaluate their inhibition performance during the task. Anodal stimulation of the dlPFC influenced response to the cognitive task during exercise, as seen by slower response times and better accuracy. However, it did not lead to any measureable improvement in cognitive inhibition and did not influence endurance time. There was no correlation between cognitive inhibition and the maintenance of physical effort. This result does not indicate a relationship between cognitive inhibition and endurance performance. The contribution of the PFC in physical endurance could be explained through its involvement on decisional processes.

Consciousness as an Inhibited Manifestation and Quantum Physics

The term soul is used in the traditional literature as a synonym for one's true Self and is associated with the subjective essence of one's living. Since, we don't have any means to quantify it, the science has ruled out this idea from its investigations. But, in a recent study, Ceylan et al. (2017) has reintroduced the word soul to scientific literature and examined the possibility of the study of the soul through scientific modalities. The primary focus of their study is to find and understand the scientific analog of the soul as quoted and discussed in the traditional literature. In the present paper, we examine the idea of a soul that uses a novel approach; integrating neuroscience and quantum physics, as proposed in Ceylan et al. (2017). For this purpose, we make use of findings from neuroscientific studies on meditation to understand the concepts of soul and consciousness in terms of inhibition mechanisms. In this context, this paper serves as an attempt to call for more studies to discuss and expand the hypothesis about the soul as uninhibited mental activity.

Self-changing behaviour in smoking cessation linked to trait and cognitive impulsivity

BACKGROUND AND AIMS

To compare impulsivity, measured using self-report and cognitive tasks in people who ceased smoking without treatment (self-changers) with each of the following groups: (i) smoking non-treatment-seekers, (ii) people in smoking cessation treatment and currently abstinent and (iii) people in smoking cessation treatment but non-abstinent.

DESIGN

Cross-sectional, observational study.

SETTING

The smoking cessation unit of a public general hospital, Hospital de Santa Maria, in Lleida, Spain. All participants were from the hospital's catchment area.

PARTICIPANTS

One hundred and twenty participants, classified in four groups: (1) self-changers (n = 30, 21 females, mean age = 41.50 years), (2) non-treatment-seekers (n = 30, 17 females, mean age = 35.27 years), (3) people in smoking cessation treatment and currently abstinent (n = 30, 17 females, mean age = 48.93 years) and (4) people in smoking cessation treatment but non-abstinent (n = 30, 21 females, mean age = 33.70 years).

MEASUREMENTS

The Barratt Impulsiveness Scale, including measures of non-planning, attentional and motor impulsivity, and two behavioural tasks measuring cognitive inhibition (Stroop test) and choice impulsivity (delay-discounting task). Confounders included sex, age, education, employment, smoking severity, depression and trait and state anxiety.

FINDINGS

Although not on the other three measures, we found significant group differences on trait non-planning impulsivity and Stroop performance. Self-changers, compared with non-treatment-seekers, had lower non-planning impulsivity (P = 0.018, Cohen's d = 0.62) and better Stroop performance (P = 0.001, Cohen's d = 0.66). Self-changers also had better Stroop performance than participants in treatment and currently abstinent (P = 0.002, Cohen's d = 0.85).

CONCLUSIONS

People who have stopped smoking without treatment appear to have lower non-planning impulsivity and more effective cognitive inhibition compared with smoking non-treatment-seekers, and better cognitive inhibition than people who cease smoking with treatment aid.

Association between hypovitaminosis D and cognitive inhibition impairment during major depression episode

BACKGROUND

Major depressive episode (MDE) has been associated with cognitive functioning alteration and hypovitaminosis D (hypoVD), but the relationship between hypoVD, depression, and cognition is not well understood. We aimed to compare patient with MDE with or without hypoVD in regard of cognitive functioning.

METHODS

91 patients (38.5 years old, 65.9% female) with MDE were included in a cross-sectional study and were evaluated with a complete cognitive battery. None of the participants were medicated at the time of the inclusion. Serum 25-hydroxyvitamin D was measured using LC-MS/MS method, and hypovitaminosis was defined as 25OHD < 50nmol/L. Covariates were gender, season of dosage, first MDE onset, age, body mass index and depression severity RESULTS: Patients with hypoVD demonstrated a higher stroop intereference index time underscoring that means low cognitive inhibition ability. Mutiple logistic regression confirmed that hypoVD was significantly associated with high stroop interference time index after controlling by gender, season of dosage, first MDE onset, age, body mass index and depression severity.

CONCLUSION

Our results suggest that patient with MDE having hypoVD may be more prone to cognitive impairment.

Cognitive inhibition in depression and suicidal behavior: a neuroimaging study

BACKGROUND

Cognitive inhibition deficits have previously been found in suicide attempters. This study examined the neural basis for these deficits in depressed patients with and without a history of suicidal behavior.

METHOD

Functional magnetic resonance imaging was used to measure brain activation during the Go/No-Go response inhibition task in 25 unmedicated and depressed middle-aged suicide attempters, 22 unmedicated depressed patient controls with no personal or family history of suicidal behavior, and 27 healthy controls. Whole-brain analyses were conducted with SPM12.

RESULTS

Suicide attempters exhibited an elevated number of commission errors relative to both control groups. However, suicide attempters did not differ from patient controls in terms of brain activation for any contrast. Analyses showed a significant association between depression and brain activation in the left inferior frontal gyrus and medial thalamus during Go v. No-Go, and in the bilateral parietal cortex and left orbitofrontal cortex during No-Go v. baseline. These regions were correlated with psychological pain, suicidal ideation and global functioning. There was no association between brain activation and personal histories of suicidal act.

CONCLUSIONS

Our study suggests that deficits in cognitive inhibition, in relation to the inferior frontal gyrus, thalamus, orbitofrontal cortex and parietal cortex, are related to the depressive state and not specifically to suicide vulnerability. We hypothesize that state-related deficits may add to trait-like cognitive impairments to facilitate suicidal acts. These different types of cognitive impairments may necessitate different therapeutic strategies for the prevention of suicide.

Executive Function Deficits in Patients after Cerebellar Neurosurgery

The cerebellum has long been perceived as a structure responsible for the human motor function. According to the contemporary approach, however, it plays a significant role in complex behavior regulatory processes. The aim of this study was to describe executive functions in patients after cerebellar surgery. The study involved 30 patients with cerebellar pathology. The control group comprised 30 neurologically and mentally healthy individuals, matched for sex, age, and number of years of education. Executive functions were measured by the Wisconsin Card Sorting Test (WCST), Stroop Color Word Test (SCWT), Trail Making Test (TMT), and working memory by the Digit Span. Compared to healthy controls, patients made more Errors and Perseverative errors in the WCST, gave more Perseverative responses, and had a lower Number of categories completed. The patients exhibited higher response times in all three parts of the SCWT and TMT A and B. No significant differences between the two groups were reported in their performance of the SCWT and TMT with regard to the measures of absolute or relative interference. The patients had lower score on the backward Digit Span. Patients with cerebellar pathology may exhibit some impairment within problem solving and working memory. Their worse performance on the SCWT and TMT could, in turn, stem from their poor motor-somatosensory control, and not necessarily executive deficits. Our results thus support the hypothesis of the cerebellum's mediating role in the regulation of the activity of the superordinate cognitive control network in the brain. (JINS, 2016, 22, 47-57).

Unraveling the sub-processes of selective attention: insights from dynamic modeling and continuous behavior

Selective attention biases information processing toward stimuli that are relevant for achieving our goals. However, the nature of this bias is under debate: Does it solely rely on the amplification of goal-relevant information or is there a need for additional inhibitory processes that selectively suppress currently distracting information? Here, we explored the processes underlying selective attention with a dynamic, modeling-based approach that focuses on the continuous evolution of behavior over time. We present two dynamic neural field models incorporating the diverging theoretical assumptions. Simulations with both models showed that they make similar predictions with regard to response times but differ markedly with regard to their continuous behavior. Human data observed via mouse tracking as a continuous measure of performance revealed evidence for the model solely based on amplification but no indication of persisting selective distracter inhibition.

Does cortisol influence core executive functions? A meta-analysis of acute cortisol administration effects on working memory, inhibition, and set-shifting

The hormone cortisol is often believed to play a pivotal role in the effects of stress on human cognition. This meta-analysis is an attempt to determine the effects of acute cortisol administration on core executive functions. Drawing on both rodent and stress literatures, we hypothesized that acute cortisol administration would impair working memory and set-shifting but enhance inhibition. Additionally, because cortisol is thought to exert different nongenomic (rapid) and genomic (slow) effects, we further hypothesized that the effects of cortisol would differ as a function of the delay between cortisol administration and cognitive testing. Although the overall analyses were nonsignificant, after separating the rapid, nongenomic effects of cortisol from the slower, genomic effects of cortisol, the rapid effects of cortisol enhanced response inhibition, g+ = 0.113, p=.016, but impaired working memory, g+ = -0.315, p=.008, although these effects reversed over time. Contrary to our hypotheses, there was no effect of cortisol administration on set-shifting. Thus, although we did not find support for the idea that increases in cortisol influence set-shifting, we found that acute increases in cortisol exert differential effects on working memory and inhibition over time.

Cognitive control and schizophrenia: The greatest reliability of the Stroop task

Three components of cognitive inhibition were compared in patients with schizophrenia and healthy controls. Nineteen patients with schizophrenia were compared to 30 healthy controls, matched for age, sex, and educational level. Cognitive inhibition was examined by (i) access to relevant information (Reading with distraction task), (ii) suppression of no longer relevant information (Trail Making Test B), and (iii) restraint of cognitive resources to relevant information (Stroop Test, Hayling Sentence Completion Test, Go/No-Go Test). Beck Depression Inventory, and Positive and Negative Syndrome Scale were also used. Compared to healthy controls, patients with schizophrenia and stabilized for at least 6 months were slower in the inhibition condition at the Stroop task, read more distractors at the RWD, and made more perseverative errors at the TMT, even after controlling for age, Mini-Mental State Examination score, information speed processing, and accuracy. This difference remained significant after taking into account the level of depressive symptoms and the severity of psychotic symptoms. In multivariate analyses, only the Stroop interference index explained cognitive inhibition deficit in patients with schizophrenia. The abnormal cognitive inhibition process observed in patients with schizophrenia could therefore concerns the ability to restraint, rather than the access or the suppression processes.

Cognitive control: componential and yet emergent

In this commentary, I will argue that the componential and emergent views of cognitive control as defined by Cooper (2010) do not necessarily oppose each other, and I will try to make a case for their interdependence. First, I will use the construct of cognitive inhibition-one of the main componential control functions mentioned in the target articles-to illustrate my line of reasoning. Then, I will comment on how some of the target articles, each from a different perspective, bring arguments in favor of this integrative view.

Blunted brain activation in patients with schizophrenia in response to emotional cognitive inhibition: a functional near-infrared spectroscopy study

INTRODUCTION

Patients with schizophrenia (SZ) have deficits of facial emotion processing and cognitive inhibition, but the brain pathophysiology underlying these deficits and their interaction are not clearly understood. We tested brain activity during an emotional face go/no-go task that requires rapid executive control affected by emotional stimuli in patients with SZ using functional near-infrared spectroscopy (fNIRS).

METHODS

Twenty-five patients with SZ and 28 healthy control subjects were studied. We evaluated behavioral performance and used fNIRS to measure oxygenated hemoglobin concentration changes in fronto-temporal areas during the emotional go/no-go task with emotional and non-emotional blocks.

RESULTS

Patients with SZ made more errors and had longer reaction times in both test blocks compared with healthy subjects. Significantly greater activation in the inferior, superior, middle, and orbital frontal regions were observed in healthy subjects during the emotional go/no-go block compared to the non-emotional go/no-go block, but this difference was not observed in patients with SZ. Relative to healthy subjects, patients with SZ showed less activation in the superior and orbital frontal and middle temporal regions during the emotional go/no-go block.

DISCUSSION

Our results suggest that fronto-temporal dysfunction in patients with SZ is due to an interaction between abnormal processing of emotional facial expressions with negative valence and cognitive inhibition, especially during the rapid selection of rule-based associations that override automatic emotional response tendencies. They indicate that fronto-temporal dysfunction is involved in the pathophysiology of emotional-cognitive deficits in patients with SZ.

Updating emotional content in working memory: a depression-specific deficit?

BACKGROUND AND OBJECTIVES

Interference from irrelevant negative material might be a key mechanism underlying intrusive ruminative thoughts in depression. Considering commonalities between depression and social anxiety and the presence of similar intrusive thoughts in social anxiety, the current study was designed to assess whether interference from irrelevant material in working memory is specific to depression or is also present in social anxiety disorder.

METHODS

To examine the effects of irrelevant emotional material on working memory performance, participants memorized two lists of words on each trial and were subsequently instructed to ignore one of the lists. Participants were then asked to indicate whether a probe word belonged to the relevant list or not.

RESULTS

Compared to control and social anxiety groups, the depression groups (both pure and comorbid with social anxiety disorder) exhibited greater difficulties removing irrelevant emotional material from working memory (i.e., greater intrusion effects). Greater intrusion effects were also associated with increased rumination.

LIMITATIONS

Although we included three clinical groups (depression, social anxiety, and the comorbid groups), the results are based on a relatively small number of participants.

CONCLUSIONS

The results indicate that difficulties removing irrelevant material from working memory might be unique to depression, and the ability to inhibit irrelevant information is relatively preserved in social anxiety disorder.

Distinct alterations in value-based decision-making and cognitive control in suicide attempters: toward a dual neurocognitive model

OBJECTIVE

The literature suggests that many suicide attempters show impairment in both decision-making and cognitive control. However, it is not clear if these deficits are linked to each other, and if they may be related to more basic alterations in attention. This is a relevant question in the perspective of future interventions targeting cognitive deficits to prevent suicidal acts.

METHOD

Two different populations of patients with histories of suicide attempts were assessed (N=142 and 119). The Iowa Gambling Task (IGT) was used to measure decision-making in both populations. We used a D2 cancellation task and a verbal working memory task in population 1; the Stroop test, the N-Back task, the Trail Making Test, and the Hayling Sentence Completion test in population 2.

RESULTS

Regarding decision-making, we only found a small negative correlation between the Hayling test error score (r=-0.24; p=0.01), and the net score from the second half of the IGT. In contrast, working memory, cognitive flexibility and cognitive inhibition measures were largely inter-correlated.

LIMITATION

Most patients were medicated. Only patients with mood disorders.

CONCLUSION

These results add to previous findings suggesting that the neurocognitive vulnerability to suicidal behavior may rely on impairments in two distinct anatomical systems, one processing value-based decision-making (associated with ventral prefrontal cortex, among others) and one underlying cognitive control (associated with more dorsal prefrontal regions). This distinction may result in tailored-made cognitive interventions.

Negative priming in amphetamine psychosis

Amphetamine abuse may lead to a psychotic state, its symptomatology being very similar to what is seen in paranoid schizophrenia. Failure of attentional inhibition of irrelevant information is thought to be associated with the psychotic symptoms in schizophrenia. Negative priming (NP) paradigm is believed to measure this impairment. Several studies have shown impaired NP in schizophrenia. In the present study a spatial NP task was used to assess attentional inhibition in a group of amphetamine-induced psychosis patients. Nineteen patients with amphetamine-induced psychotic disorder and 20 healthy subjects participated in this study. Severity of psychotic symptoms was measured prior to testing using the Brief Psychiatric Rating Scale (BPRS). Patients showed no deficit in NP, and the amount of their NP effect was not significantly different from healthy subjects. Besides, we did not find any correlation between the amount of NP effect and severity of symptoms. Our results may indicate that cognitive mechanisms underlying NP might not be affected in amphetamine psychosis.

Subjective sleep quality in relation to inhibition and heart rate variability in patients with panic disorder

BACKGROUND

Patients with panic disorder (PD) are known to report impaired sleep quality and symptoms of insomnia. PD is an anxiety disorder characterised by deficient physiological regulation as measured by heart rate variability (HRV), and reduced HRV, PD and insomnia have all been related to impaired inhibitory ability. The present study aimed to investigate the interrelationships between subjectively reported sleep impairment, cognitive inhibition and vagally mediated HRV in a sample characterised by variability on measures of all these constructs.

METHODS

Thirty-six patients with PD with or without agoraphobia were included. Cognitive inhibition was assessed with the Color-Word Interference Test from the Delis-Kaplan Executive Function System (D-KEFS), HRV was measured using high frequency (HF) power (ms(2)), and subjectively reported sleep quality was measured with the Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Cognitive inhibition was related to both Sleep latency and Sleep disturbances, whereas HRV was only related to Sleep disturbances. These relationships were significant also after controlling for depression.

LIMITATIONS

Correlational design.

CONCLUSION

Cognitive inhibition is related to key insomnia symptoms: sleep initiation and sleep maintenance. The data supports the psychobiological inhibition model of insomnia, and extends previous findings. Possible clinical implications of these findings are discussed.