Insights into the neural basis of response inhibition from cognitive and clinical neuroscience

Reduced recruitment of inhibitory control regions in very young children with ADHD during a modified Kiddie Continuous Performance Task: A fMRI study

Attention-Deficit/Hyperactivity Disorder (ADHD) symptom profiles are known to undergo changes throughout development, rendering the neurobiological assessment of ADHD challenging across different developmental stages. Particularly in young children (ages 4- to 7-years), measuring inhibitory control network activity in the brain has been a formidable task due to the lack of child-friendly functional Magnetic Resonance Imaging (fMRI) paradigms. This study aims to address these difficulties by focusing on measuring inhibitory control in very young children within the MRI environment. A total of 56 children diagnosed with ADHD and 78 typically developing (TD) 4-7-year-old children were successfully examined using a modified version of the Kiddie-Continuous Performance Test (K-CPT) during BOLD fMRI to assess inhibitory control. We also evaluated their performance on the standardized K-CPT outside the MRI scanner. Our findings suggest that the modified K-CPT effectively elicited robust and expected brain activity related to inhibitory control in both groups who were successfully scanned. Comparisons between the two groups revealed differences in brain activity, primarily observed in inferior frontal gyrus, anterior insula, dorsal striatum, medial pre-supplementary motor area (pre-SMA), and cingulate cortex (p < .005, corrected). Notably, for both groups increased activity in the right anterior insula was associated with improved response time (RT) and reduced RT variability on the K-CPT administered outside the MRI environment, although this did not survive statistical correction for multiple comparisons. The study also revealed continuing challenges for scanning this population-an additional 51 TD children and 78 children with ADHD were scanned, but failed to provide useable data due to movement. In summary, for a subsample of children, we successfully overcame some of the challenges of measuring inhibitory control in very young children within the MRI environment by using a modified K-CPT during BOLD fMRI, but further challenges remain for scanning in this population. The findings shed light on the neurobiological correlates of inhibitory control in ADHD and TD children, provide valuable insights for understanding ADHD across development, and potentially inform ADHD diagnosis and intervention strategies. The research also highlights remaining challenges with task fMRI in very young clinical samples.

A meta-analytic investigation of the effect of sleep deprivation on inhibitory control

Sleep deprivation may have a deleterious effect on inhibitory control; however, this effect is not consistent across studies. To arrive at an overall estimate of the relationship between sleep deprivation and inhibitory control, this report used meta-analysis to summarise the magnitude of the effects of sleep deprivation on inhibitory control as measured by the Go/No-Go and Stop Signal Tasks. These are two widely used tasks in the literature. A systematic search of four databases (APAPsycINFO, Medline, CINAHL and Embase) from their inception to November 2023 identified 24 studies involving 712 healthy individuals. Separate random-effects models were used to estimate the effect size of sleep deprivation on performance in these tasks. The meta-analysis revealed a moderate negative effect of sleep deprivation on inhibitory control in both the Go/No-Go and Stop Signal Tasks. Given the importance of inhibitory control in everyday behaviour, future research should investigate the neural and neurophysiological mechanisms underlying this relationship and explore its impact in clinical populations.

Frontal localisation of a theory-based anxiety disorder biomarker - Goal conflict specific rhythmicity

PURPOSE

Anxiety disorders are a major global issue. Diagnosis via symptoms, not biological causes, delivers poor treatment outcomes. Our frontal EEG biomarker, Goal Conflict Specific Rhythmicity (GCSR; 4-12 Hz), developed from our long-standing detailed neuropsychological theory of anxiety processes, is reduced by all chemical types of selective anxiolytic and is high in cases across a range of currently diagnosed anxiety disorders.

METHODS

We assessed frontal sources of GCSR, recording scalp EEG at either low resolution (Experiment 1, 32 channels, University of Otago, ♀:33, ♂:16) or high resolution (Experiment 2, 128 channels, University of Auckland, ♀:10, ♂:8) in healthy participants performing a Stop Signal Task to generate GCSR as previously.

PRINCIPAL RESULTS

sLORETA demonstrated GCSR sources consistently in the right inferior frontal gyrus and, more strongly but less consistently, medial frontal gyrus. Variation was consistent with that of stopping in the same Stop Signal Task, depending on task demands.

MAJOR CONCLUSIONS

The sources of GCSR are consistent with our theory that hippocampal output receives goal information, detects conflict, and returns a negative biasing signal to the areas encoding goals in the current task. They match the variation in the control of stopping when response urgency changes. GCSR appears to index a biological type of anxiety unlike any current diagnosis and should help improve accuracy of diagnosis - anchored to actions of selective anxiolytic drugs. This task-related frontal "theta" rhythmicity provides proof-of-concept for further development of our theory of the neuropsychology of anxiety in direct human tests.

Vagally-mediated heart rate variability longitudinally predicts test anxiety in university students

BACKGROUND AND OBJECTIVES

Self-regulatory processes, namely behavioral regulation (in terms of executive functions) and emotion regulation, are assumed to be central for test anxiety. Both self-regulation components, along with vagally-mediated heart rate variability (HRV) - a proposed concomitant of top-down self-regulation - are associated with anxiety.

DESIGN

A longitudinal design was adopted to test the hypotheses that (1) higher vagally-mediated HRV, (2) adaptive emotion regulation and (3) better executive functioning (i.e., higher inhibitory control) at the semester beginning (t1) predict lower levels of test anxiety at the end of the semester (t2).

METHODS

A sample of N = 70 (58 female) university students (M [SD] age = 25.04 [7.14] years) completed a measurement of resting HRV (RMSSD), performed an affective go/no-go task, and reported on emotion regulation and test anxiety at t1. Test anxiety and certain examination characteristics were assessed at t2. A hierarchical regression analysis was conducted to test the hypotheses.

RESULTS

Supporting hypothesis 1, HRV at t1 significantly predicted test anxiety at t2, whereas emotion regulation and inhibitory control were no significant predictors.

CONCLUSIONS

As vagally-mediated HRV seems meaningful for the prediction of test anxiety, interventions designed to reduce test anxiety could benefit from incorporating HRV biofeedback training.

Computational mechanism underlying switching of motor actions

Survival of species in an ever-changing environment requires a flexibility that extends beyond merely selecting the most appropriate actions. It also involves readiness to stop or switch actions in response to environmental changes. Although considerable research has been devoted to understanding how the brain switches actions, the computations underlying the switching process and how it relates to the selecting and stopping processes remain elusive. A normative theory suggests that switching is simply an extension of the stopping process, during which a current action is first inhibited by an independent pause mechanism before a new action is generated. This theory was challenged by the affordance competition hypothesis, according to which the switching process is implemented through a competition between the current and new actions, without engaging an independent pause mechanism. To delineate the computations underlying these action regulation functions, we utilized a neurocomputational theory that models the process of selecting, stopping and switching reaching movements. We tested the model predictions in healthy individuals who performed reaches in dynamic and uncertain environments that often required stopping and switching actions. Our findings suggest that unlike the stopping process, switching does not necessitate a proactive pause mechanism to delay movement initiation. Hence, the switching and stopping processes seem to be implemented by different mechanisms at the planning phase of the reaching movement. However, once the reaching movement has been initiated, the switching process seems to involve an independent pause mechanism if the new target location is unknown prior to movement initiation. These findings offer a new understanding of the computations underlying action switching, contribute valuable insights into the fundamental neuroscientific mechanisms of action regulation, and open new avenues for future neurophysiological investigations.

Cross-Modal Transfer Effects of the Go/No-Go Training With Visual Stimuli

INTRODUCTION

Motor task performance guided by one sensory modality (e.g., visual stimuli) can be improved by training; however, whether this training can also improve performance on the same task guided by another sensory modality remains uncertain (e.g., tactile stimuli). This study examined the effects of Go/No-go task training using visual stimulus cues on Go/No-go task performance using tactile cues and whether training also influences the dominance of the sensory modality.

METHODS

Go/No-go tasks and a temporal order judgment (TOJ) task were performed by 24 right-handed, healthy adults on days 1 and 5 of the 5-day experiment. Furthermore, a subpopulation (the training group) practiced the Go/No-go task with visual stimulus cues on days 2-4, whereas the remaining control group did not practice the task.

RESULTS

The training group demonstrated significantly reduced reaction times (RTs) on both the visual and tactile Go/No-go tasks by day 5, whereas the control group demonstrated significantly reduced RTs only on the tactile Go/No-go task. The RT change was also significantly greater in the training group than in the control group for both modalities. Conversely, no significant change in the TOJ for visual and tactile stimuli was observed between the groups.

CONCLUSION

These results indicate that motor training with visual guidance can improve performance on the same task guided by tactile stimuli, possibly due to neuroplastic changes in the multimodal association cortices.

Efficacy and Safety of Transcranial Magnetic Stimulation for Attention-Deficit Hyperactivity Disorder: A Systematic Review and Meta-Analysis

BACKGROUND

Transcranial magnetic stimulation (TMS) is a promising neuromodulation technique that has been widely used in neuropsychiatric disorders, but there was no evidence on its effect on the improvement attention-deficit hyperactivity disorder (ADHD).

OBJECTIVE

This systematic review and meta-analysis aimed to investigate the efficacy and safety of TMS in reducing ADHD symptoms.

METHOD

We systematically searched four databases (PubMed, Embase, Web of Science, and Cochrane Library databases) for randomized controlled/crossover trials on the efficacy and safety of TMS on ADHD symptom improvement compared to sham rTMS or non-TMS interventions, published until September 18, 2024. Extracted data from the included studies involved patient characteristics, intervention protocols, and main outcomes. The effect size of the TMS treatment was evaluated using the standardized mean difference (SMD) with a 95% confidence interval (CI), calculated with either a random effects model or fixed effects model depending on the level of heterogeneity.

RESULT

Eight studies (325 ADHD patients in total) were included in this systematic review and meta-analysis. According to the core symptoms, TMS significantly improved inattention (SMD = -0.94, 95% CI = -1.33 to -0.56, p < 0.001) and hyperactivity/impulsivity (SMD = -0.98, 95% CI = -1.27 to -0.69, p < 0.001) compared to non-TMS interventions after 3-6 weeks of intervention. During the 1-month follow-up, the TMS group still demonstrated a significant improvement in inattention symptoms compared to the non-TMS group (SMD = -0.67, 95% CI = -1.06 to 0.28, p < 0.001). The total symptoms in the TMS group only showed improvement in the 1-month follow-up compared to the non-TMS group. (SMD = -0.48, 95% CI = -0.82 to -0.14, p = 0.005). Only minor adverse events were reported in the included studies, comprising headache and scalp discomfort.

CONCLUSION

TMS significantly improved the inattention, hyperactivity/impulsivity, and total symptom scores in ADHD patients with minor adverse events. Future research should focus on the association between different brain regions and symptoms in ADHD patients, which is crucial for stimulation navigation in TMS interventions. The trial is registered in PROSPERO (PROSPERO registry number: CRD42023473853).

Multiple insular-prefrontal pathways underlie perception to execution during response inhibition in humans

Inhibiting prepotent responses in the face of external stop signals requires complex information processing, from perceptual to control processing. However, the cerebral circuits underlying these processes remain elusive. In this study, we used neuroimaging and brain stimulation to investigate the interplay between human brain regions during response inhibition at the whole-brain level. Magnetic resonance imaging suggested a sequential four-step processing pathway: initiating from the primary visual cortex (V1), progressing to the dorsal anterior insula (daINS), then involving two essential regions in the inferior frontal cortex (IFC), namely the ventral posterior IFC (vpIFC) and anterior IFC (aIFC), and reaching the basal ganglia (BG)/primary motor cortex (M1). A combination of ultrasound stimulation and time-resolved magnetic stimulation elucidated the causal influence of daINS on vpIFC and the unidirectional dependence of aIFC on vpIFC. These results unveil asymmetric pathways in the insular-prefrontal cortex and outline the macroscopic cerebral circuits for response inhibition: V1→daINS→vpIFC/aIFC→BG/M1.

Disentangling inhibition toward food and non-food stimuli across two hunger levels: An fNIRS study

While individuals tend to display poorer inhibitory control toward food-related than neutral stimuli, it is unclear whether this challenge is specific to food or extends to other pleasant stimuli. Uncertainty also remains regarding the general impact of hunger on inhibition. To address these questions, we used a within-subjects design whereby 44 healthy adults completed two go/no-go tasks including no-go images of highly palatable foods and no-go images of animals matched for valence and physical properties. Both tasks were completed one week apart in either a fed or a fasted state. Prefrontal cortex activity was measured using functional near-infrared spectroscopy. Poorer behavioral inhibition was observed when participants needed to withhold their response to images of food compared to animals, regardless of hunger state. In addition, more commission errors were made in the fasted compared to the fed condition, regardless of the type of image to avoid responding to. Responses to go trials were slower when these trials were interspersed with food compared to animal no-go trials. However, hunger did not influence go response time. Greater activation was observed in the dorsolateral prefrontal cortex during blocks of trials with (vs. without) no-go images, but brain activity did not differ according to the type of no-go image. The effect of hunger on prefrontal brain activity was also not significant. Exploratory correlations showed that food-related inhibition deficits were positively related to self-reported impulsivity, but unrelated to body mass index. This study suggests that even among healthy adults, food-related inhibitory control may have a unique behavioral signature beyond general inhibition toward pleasant stimuli. Hunger also exerts an independent influence on general inhibitory capabilities, highlighting the importance of carefully controlling hunger levels in inhibition studies.

Concurrent oculomotor hyperactivity and deficient anti-saccade performance in obsessive-compulsive disorder

Existing studies mainly focused on the inhibition of the task-interfering response to understand the inhibitory deficits of obsessive-compulsive disorder (OCD). However, recent studies suggested that inhibitory function is broadly involved in response preparation and implementation. It is yet unknown if the inhibition dysfunction in OCD extends beyond the task-interfering response to the general inhibitory function. Here we address this issue based on the multidimensional eye-movement measurements, which can better capture the inhibitory deficits than manual responses. Thirty-one OCD patients and 32 healthy controls (HCs) completed the anti-saccade task where multidimensional eye-movement features were developed. Confirmatory factor analysis (CFA) suggested two components of inhibitory function that negatively correlated with each other: one component of oculomotor hyperactivity in generating oculomotor output which is characterized with early premature saccades, early cross rates and saccade number; the other component of task-specific oculomotor efficiency which is characterized with task accuracy, saccade latency, correction rate, and amplitude gain. Importantly, OCD showed both stronger oculomotor hyperactivity and deficient oculomotor efficiency than HCs, and the machine-learning-based classifications showed that the features of oculomotor hyperactivity had higher prediction accuracy than the features of oculomotor efficiency in distinguishing OCD from HCs. Our results suggested that OCD has concurrent deficits in oculomotor hyperactivity and oculomotor efficiency, which may originate from a common inhibitory dysfunction.

Effects of total sleep deprivation on functional connectivity of the anterior cingulate cortex: Insights from resting-state fMRI in healthy adult males

Inadequate sleep significantly impacts an individual's health by compromising inhibitory control and self-regulation abilities. This study employed resting-state functional magnetic resonance imaging (fMRI) to assess the functional connectivity between the anterior cingulate cortex (ACC) and the whole brain in 16 healthy adult males after 36 h of total sleep deprivation. Additionally, this study investigated alterations in individuals' inhibitory control functions and physiological mechanisms following sleep deprivation. The results showed a significant increase in functional connectivity between the ACC, the left angular gyrus, and the right hippocampus following 36 h of continuous sleep deprivation. Conversely, functional connectivity was notably decreased between the ACC and the right insular cortex, right paracingulate gyrus, and bilateral putamen. Furthermore, changes in ACC functional connectivity were significantly correlated with alterations in behavioral performance in the go/no-go task after sleep deprivation. This study contributes to understanding brain network mechanisms in the anterior cingulate gyrus after sleep deprivation. It clarifies the relationship between functional connectivity changes in the anterior cingulate gyrus and inhibitory control post-sleep deprivation.

Does Body Postural Configuration Affect Upper Limb Performance During Point-to-Point Hand Movements?

Adopting a postural configuration may be regarded as preparation for the performance of an upcoming movement. However, it is unclear how different postural configurations affect motor performance. The aim of the current study was to examine how body posture - sitting versus standing - influences fast and accurate planar point-to-point hand movements. Twenty-three healthy adults performed a "Go/No-go" paradigm while doing repetitive point-to-point movements. Arousal levels, which may change due to the change in posture, were independently manipulated by using a sham threat of electrical stimulation. Upper limb kinematics, center of pressure displacement, and galvanic skin responses were recorded in four test conditions: sitting and standing with and without arousal manipulation. Descriptive performance measures were computed and analyzed using multiple analyses of variance. A difference in arousal level was observed in the two conditions with the arousal manipulation, but no difference in arousal level was found between sitting and standing. Center of pressure displacement onset was found to be earlier in the two standing conditions compared to those in sitting. No difference was found in upper limb performance between the two postures, nor due to the arousal manipulation. We concluded that under the tested conditions, body posture does not appear to affect upper limb performance.

Response inhibition as a critical executive function in differentiating attention-deficit/hyperactivity disorder from autism spectrum disorder: a comprehensive attention test study

Background

Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) are both associated with impairment in executive function, particularly in complex attention. Although previous studies using clinical assessments have attempted to delineate differences between these disorders, the findings have been inconclusive. Our study aims to elucidate the differences of endophenotype between ASD, ADHD, and their co-occurring condition utilizing a uniform computerized test.

Methods

The study included children diagnosed with ASD, ASD co-occurring with ADHD (ASD+ADHD), or ADHD who completed the comprehensive attention test (CAT) at Severance Hospital between October 2013 to May 2023. We excluded children with intellectual disability and comorbid major psychiatric or neurologic disorders possibly affecting attention measurement. The participants were categorized into three groups for the comparative analysis of CAT measures: (a) ASD (n=112), (b) ASD+ADHD (n=155), and (c) ADHD (n=104). The study also conducted an exploratory analysis utilizing multivariate linear regression analysis to examine the association between the CAT measures and parent-reported scales.

Results

Notably, the ASD+ADHD and ADHD groups exhibited higher frequency of commission errors (CE) and perseveration errors (PE) compared to the ASD group. In the exploratory analysis, a significant negative association was observed between reaction time (RT) and both the social communication questionnaire (SCQ) and the child behavior checklist (CBCL) externalization scores in the ASD+ADHD and ADHD groups. The ASD+ADHD group tended to show higher standard deviation of reaction time (RTSD) compared to the ASD group.

Conclusions

Our findings suggest that impaired response inhibition is more pronounced in ADHD compared to ASD. We propose altered visual attention, reflecting response inhibition, may serve as potential endophenotypic markers differentiating ADHD from ASD in attentional assessment. Elevated RTSD in the ASD+ADHD group demonstrates additive pathology, suggesting that the neurological mechanisms underpinning impaired sustained attention may differ between the two conditions.

Inhibitory control of gait initiation in humans: An electroencephalography study

Response inhibition is a crucial component of executive control. Although mainly studied in upper limb tasks, it is fully implicated in gait initiation. Here, we assessed the influence of proactive and reactive inhibitory control during gait initiation in healthy adult participants. For this purpose, we measured kinematics and electroencephalography (EEG) activity (event-related potential [ERP] and time-frequency data) during a modified Go/NoGo gait initiation task in 23 healthy adults. The task comprised Go-certain, Go-uncertain, and NoGo conditions. Each trial included preparatory and imperative stimuli. Our results showed that go-uncertainty resulted in delayed reaction time, without any difference for the other parameters of gait initiation. Proactive inhibition, that is, Go uncertain versus Go certain conditions, influenced EEG activity as soon as the preparatory stimulus. Moreover, both proactive and reactive inhibition influenced the amplitude of the ERPs (central P1, occipito-parietal N1, and N2/P3) and theta and alpha/low beta band activities in response to the imperative-Go-uncertain versus Go-certain and NoGo versus Go-uncertain-stimuli. These findings demonstrate that the uncertainty context; induced proactive inhibition, as reflected in delayed gait initiation. Proactive and reactive inhibition elicited extended and overlapping modulations of ERP and time-frequency activities. This study shows the protracted influence of inhibitory control in gait initiation.

The relationship between structural properties of frontal cortical regions and response inhibition in 6-14-year-old children

Development of attentional skills and inhibitory control rely on maturational changes in the brain across childhood and youth. However, both brain anatomy and different components of attention and inhibition show notable individual variation. Research on ADHD and inhibitory training and control have shown that variations in the thickness and surface area of particularly inferior cortical structures are associated with attentional control. However, the intricacies of how the development of inhibitory control is associated with the anatomical variations beyond the general age- and gender-dependent differences have not been resolved. Here, we sought to address these questions by quantifying the cortical thickness and surface area in frontal cortical regions and inhibitory control using the stop signal task performance in 6-14-year-old children. Our results showed that the thickness of the left medial orbitofrontal cortex and the surface area of the left caudal anterior cingulate were associated with the inhibitory performance, beyond the variance that could be explained by the subjects' age and gender. The results highlight the importance of factoring in anatomical variations when following attentional development and the importance of evaluating multiple anatomical measures when aiming to link the properties of cortical structures with variations in cognitive performance.

The Role of Anatomic Connectivity in Inhibitory Control Revealed by Combining Connectome-based Lesion-symptom Mapping with Event-related Potentials

Inhibitory control refers to the ability to suppress cognitive or motor processes. Current neurocognitive models indicate that this function mainly involves the anterior cingulate cortex and the inferior frontal cortex. However, how the communication between these areas influence inhibitory control performance and their functional response remains unknown. We addressed this question by injecting behavioral and electrophysiological markers of inhibitory control recorded during a Go/NoGo task as the 'symptoms' in a connectome-based lesion-symptom mapping approach in a sample of 96 first unilateral stroke patients. This approach enables us to identify the white matter tracts whose disruption by the lesions causally influences brain functional activity during inhibitory control. We found a central role of left frontotemporal and frontobasal intrahemispheric connections, as well as of the connections between the left temporoparietal and right temporal areas in inhibitory control performance. We also found that connections between the left temporal and right superior parietal areas modulate the conflict-related N2 event-related potential component and between the left temporal parietal area and right temporal and occipital areas for the inhibition P3 component. Our study supports the role of a distributed bilateral network in inhibitory control and reveals that combining lesion-symptom mapping approaches with functional indices of cognitive processes could shed new light on post-stroke functional reorganization. It may further help to refine the interpretation of classical electrophysiological markers of executive control in stroke patients.

The dual nature of working memory deficits: methamphetamine abusers have more impaired social working memory capacity than canonical working memory capacity

Social working memory (WM) temporarily retains and manipulates various aspects of social information. Extensive research has highlighted impaired social cognitive functions in individuals with substance addiction. However, the specific deficit in social WM within this population remains notably understudied. Bridging this gap, we investigated social WM capacity using biological motion (BM) stimuli in methamphetamine (MA) abusers compared to an inmate control group, alongside contrasting these findings with their canonical WM deficits. Across two studies, we recruited female MA abusers (N = 80) undergoing post-isolation rehabilitation within a mandatory confinement circumstance. To ensure a pertinent comparison, we recruited female inmates (N = 80) subjected to comparable confinement. Results show substantial BM WM impairment in MA abusers, yet non-BM WM remains mostly intact. These findings highlight a pronounced social WM deficit in MA abusers, surpassing their canonical WM deficit relative to inmate controls. This suggests a distinct dissociation between social and canonical WM processing.

Inhibitory control and academic achievement - a study of the relationship between Stroop Effect and university students' academic performance

While previous research has identified executive functions as predictors of academic performance in school children, similar studies conducted among adults show mixed results. One of the reasons given for executive functions having a limited effect on academic achievements in adulthood is that they are usually fully developed by that time. Since these executive functions are at their peak at that age, the individual differences in these as well as their influence on academic performance in adults are harder to trace. The paper describes a study conducted among 107 university students the goal of which was to find out whether there is any relationship between the adult students' inhibitory control values measured with the Stroop Test and their academic achievements. Although the results indicate a weak correlation between the Stroop Effect and the students' academic performance of low statistical significance, which seems to confirm the outcomes of the previous studies focusing on adults, the study reveals an unexpected statistically significant correlation between the students' grade averages and the number of their incorrect color identifications. This phenomenon appears to be worth pursuing in future research since it suggests the existence of another, relatively quickly measurable, variable possibly reflecting other predictors of academic performance in adults such as a degree of their manifested conscientiousness, their ability to concentrate on an assigned, relatively short, one-off task and their attitude to fulfilling this task. The Stroop Test, despite not being originally designed for this purpose, might thus be used as a simple tool suitable for providing information about these variables via the subject's number of color identification errors. Such information can subsequently inform the activities that educators may include in their curricula to foster conscientiousness and concentration in the students lacking these.

The bidirectional influence between emotional language and inhibitory control in Chinese: An ERP study

The bidirectional influence between emotional language and inhibitory processes has been studied in alphabetic languages, highlighting the need for additional investigation in nonalphabetic languages to explore potential cross-linguistic differences. The present ERP study investigated the bidirectional influence in the context of Mandarin, a language with unique linguistic features and neural substrates. In Experiment 1, emotional adjectives preceded the Go/NoGo cue. The ERPs revealed that negative emotional language facilitated inhibitory control. In Experiment 2, with a Go/NoGo cue preceding the emotional language, the study confirmed that inhibitory control facilitated the semantic integration of negative language in Chinese, whereas the inhibited state may not affect deeper refinement of the emotional content. However, no interaction was observed in positive emotional language processing. These results suggest an interaction between inhibitory control and negative emotional language processing in Chinese, supporting the integrative emotion-cognition view.

Neural indices of heritable impulsivity: Impact of the COMT Val158Met polymorphism on frontal beta power during early motor preparation

Studies of COMT Val158Met suggest that the neural circuitry subserving inhibitory control may be modulated by this functional polymorphism altering cortical dopamine availability, thus giving rise to heritable differences in behaviors. Using an anatomically-constrained magnetoencephalography method and stratifying the sample by COMT genotype, from a larger sample of 153 subjects, we examined the spatial and temporal dynamics of beta oscillations during motor execution and inhibition in 21 healthy Met158/Met158 (high dopamine) or 21 Val158/Val158 (low dopamine) genotype individuals during a Go/NoGo paradigm. While task performance was unaffected, Met158 homozygotes demonstrated an overall increase in beta power across regions essential for inhibitory control during early motor preparation (∼100 ms latency), suggestive of a global motor "pause" on behavior. This increase was especially evident on Go trials with slow response speed and was absent during inhibition failures. Such a pause could underlie the tendency of Met158 allele carriers to be more cautious and inhibited. In contrast, Val158 homozygotes exhibited a beta drop during early motor preparation, indicative of high response readiness. This decrease was associated with measures of behavioral disinhibition and consistent with greater extraversion and impulsivity observed in Val homozygotes. These results provide mechanistic insight into genetically-determined interindividual differences of inhibitory control with higher cortical dopamine associated with momentary response hesitation, and lower dopamine leading to motor impulsivity.

Neural correlates of impulsivity in amphetamine use disorder

Impulsivity is a trait associated with several psychiatric conditions, not least addictive disorders. While the neural mechanisms behind certain aspects of impulsivity have been studied extensively, there are few imaging studies examining this neurocircuitry in populations with substance use disorders. Therefore, we aimed to examine the functional connectivity of relevant neural networks, and their possible association with trait impulsivity, in a sample with severe amphetamine use disorder and a control group of healthy subjects. We used data collected in a randomized clinical trial studying the acute effects of oral naltrexone in amphetamine use disorder. Our final sample included 32 amphetamine users and 27 healthy controls. Trait impulsivity was rated with the Barratt Impulsiveness Scale-11, and functional connectivity was measured during resting-state fMRI, looking specifically at networks involving prefrontal regions previously implicated in studies of impulsivity. Amphetamine users had higher subjective ratings of impulsivity as compared to healthy controls, and these scores correlated positively with a wide-spread prefrontal hyperconnectivity that was found among the amphetamine users. These findings highlight the importance of aberrant prefrontal function in severe addiction.

Executive functions and addictions: a Structural Equation Modeling Approach and the Italian validation of the Adult Executive Functioning Inventory (ADEXI)

INTRODUCTION

the work aims to observe the associations between psychoactive substance use and gambling and executive functioning as well as to validate the Italian version of the "Adult Executive Functioning Inventory" (ADEXI) scale.

METHODS

data were collected through a representative cross-sectional study among 5,160 people (18-84 years old) called IPSAD® (Italian Population Survey on Alcohol and Other Drugs). Structural Equation Modeling (SEM) was performed to explore the associations between ADEXI and other behaviors measured with standardized questionnaires. Cronbach α has been performed to investigate the psychometric properties of the Italian version of the ADEXI scale.

RESULTS

SEM showed that both WM and INH were correlated with problematic cannabis use (WM r = 0.112; INH r = 0.251) and gambling (WM r = 0.101; INH r = 0.168), while problematic alcohol use was correlated only with INH (r = 0.233). Cronbach α for the WM subscale was 0.833 (CI 0.826-0.840), while for INH was 0.694 (CI 0.680-0.708).

CONCLUSION

results pointed out a strong correlation between addictions (substance-related and non-substance-related) and WM and INH impairments among the adult general population. Moreover, the ADEXI scale could be considered a valuable tool for general population surveys to detect working memory and inhibition characteristics.

Circadian rhythm sleep loss impairs motor inhibition more than motor execution in continuous action

Under total sleep deprivation, both inhibitory and motor control are impaired. However, how circadian rhythm sleep loss caused by irregular sleep pattern affects motor inhibition and execution in continuous actions remains unknown. This study utilized a pointing task to investigate the question over 30 days. During regular trials, participants were instructed to tap on a specified location, while in countermanding trials, they were required to countermand their current action. Additionally, there was a control group performed the same task following a normal 24-h rhythm. The results indicated that the decrease in accuracy and the increase in movement time in countermanding trials were more prominent in the shift work group. In contrast, there was no significant difference in reaction time between the two groups. Notably, the shift work group outperformed the control group in terms of movement time in regular trials and radial displacement in countermanding trials. Overall, these results show that circadian rhythm sleep loss predominantly affects inhibitory control, rather than motor control, underscoring the nuanced impacts of sleep disruption on differential aspects of cognitive and motor functions.

Towards optimized methodological parameters for maximizing the behavioral effects of transcranial direct current stimulation

Introduction

Transcranial direct current stimulation (tDCS) administers low-intensity direct current electrical stimulation to brain regions via electrodes arranged on the surface of the scalp. The core promise of tDCS is its ability to modulate brain activity and affect performance on diverse cognitive functions (affording causal inferences regarding regional brain activity and behavior), but the optimal methodological parameters for maximizing behavioral effects remain to be elucidated. Here we sought to examine the effects of 10 stimulation and experimental design factors across a series of five cognitive domains: motor performance, visual search, working memory, vigilance, and response inhibition. The objective was to identify a set of optimal parameter settings that consistently and reliably maximized the behavioral effects of tDCS within each cognitive domain.

Methods

We surveyed tDCS effects on these various cognitive functions in healthy young adults, ultimately resulting in 721 effects across 106 published reports. Hierarchical Bayesian meta-regression models were fit to characterize how (and to what extent) these design parameters differentially predict the likelihood of positive/negative behavioral outcomes.

Results

Consistent with many previous meta-analyses of tDCS effects, extensive variability was observed across tasks and measured outcomes. Consequently, most design parameters did not confer consistent advantages or disadvantages to behavioral effects-a domain-general model suggested an advantage to using within-subjects designs (versus between-subjects) and the tendency for cathodal stimulation (relative to anodal stimulation) to produce reduced behavioral effects, but these associations were scarcely-evident in domain-specific models.

Discussion

These findings highlight the urgent need for tDCS studies to more systematically probe the effects of these parameters on behavior to fulfill the promise of identifying causal links between brain function and cognition.

The homogenous hippocampus: How hippocampal cells process available and potential goals

We present here a view of the firing patterns of hippocampal cells that is contrary, both functionally and anatomically, to conventional wisdom. We argue that the hippocampus responds to efference copies of goals encoded elsewhere; and that it uses these to detect and resolve conflict or interference between goals in general. While goals can involve space, hippocampal cells do not encode spatial (or other special types of) memory, as such. We also argue that the transverse circuits of the hippocampus operate in an essentially homogeneous way along its length. The apparently different functions of different parts (e.g. memory retrieval versus anxiety) result from the different (situational/motivational) inputs on which those parts perform the same fundamental computational operations. On this view, the key role of the hippocampus is the iterative adjustment, via Papez-like circuits, of synaptic weights in cell assemblies elsewhere.

A differential impact of action-effect temporal contiguity on different measures of response inhibition in the Go\No-Go and Stop-signal paradigms

Response inhibition refers to suppressing a prepotent motor response and is often studied and discussed as an act of cognitive control. Much less attention was given to the potential contribution of motor control processes to response inhibition. Accumulated empirical findings show that a perceptual effect temporally contiguous with a response improves motor control performance. In the current study, we followed this work by manipulating action-effect temporal contiguity to enhance motor performance and investigated its impact on response selection and inhibition. In two experiments, we integrated a Go/No-Go (GNGT; Experiment 1) and a Stop-signal (SST; Experiment 2) task with the Effect-Motivation task, previously used to capture the facilitating impact of action-effect temporal contiguity on response times (RTs). Replicating previous findings, RTs were shorter following temporally contiguous compared to Lagged action-effect in Go trials in both the GNGT (Experiment 1) and SST (Experiment 2). Notably, an Immediate action-effect improved response inhibition in the GNGT (Experiment 1) but did not modulate Stop-signal reaction time (SSRT) in the SST (Experiment 2). Unexpectedly, the error rate on Go trials was higher in the Immediate effect condition in Experiment 2. We interpret the findings to suggest that an action's (Immediate) perceptual effect may promote response inhibition performance by enhancing selective association between the Go stimuli and the Go response and not by improving cognitive control ability. The findings also imply that an Immediate action-effect may hamper action control (e.g., by increasing general readiness to respond), at least when action control does not benefit from automatic stimulus-response association.

The behavioral component of sexual inhibition and its relation with testosterone levels: An fMRI study in transgender and cisgender individuals

Many transgender individuals report having difficulties with initiating and seeking sexual contacts. Relatively to cisgender individuals, transgender individuals are more likely to avoid sexual activity, indicating that the groups might differ in the neural underpinnings of the behavioral component of sexual inhibition. In this fMRI study, transgender (n = 33) and cisgender (n = 34) participants performed an Approach Avoidance Task (AAT) assessing sexual inhibition. We found that over the entire sample, the task elicited brain activation commonly associated with general and sexual inhibition, for instance in the bilateral insula, right inferior parietal lobule, and right inferior and middle frontal gyri. Upon investigating group differences between transgender and cisgender participants, we mainly found similarities in neural activation during the task. However, there were group differences in regions involved in decision making processes (left middle temporal gyrus) and sexual response inhibition (right anterior cingulate cortex and left inferior parietal lobule). In order to investigate whether these group differences were modulated by testosterone levels, we performed ROI-analyses assessing the relationship between testosterone and neural activation during the AAT (controlling for sex assigned at birth), but no correlations were found. On the whole brain level, however, we found that testosterone correlated positively with cerebral activation in the right claustrum (a region associated with sexual arousal) during the approach of sexual stimuli in the transgender group. Overall, these findings indicate that transgender and cisgender individuals mostly show similarities in their neural response to a sexual Approach-Avoidance task, and that testosterone levels are unlikely to play an important role.

On the interplay between state-dependent reconfigurations of global signal correlation and BOLD fluctuations: An fMRI study

BACKGROUND

The dynamics of global, state-dependent reconfigurations in brain connectivity are yet unclear. We aimed at assessing reconfigurations of the global signal correlation coefficient (GSCORR), a measure of the connectivity between each voxel timeseries and the global signal, from resting-state to a stop-signal task. The secondary aim was to assess the relationship between GSCORR and blood-oxygen-level-dependent (BOLD) activations or deactivation across three different trial-conditions (GO, STOP-correct, and STOP-incorrect).

METHODS

As primary analysis we computed whole-brain, voxel-wise GSCORR during resting-state (GSCORR-rest) and stop-signal task (GSCORR-task) in 107 healthy subjects aged 21-50, deriving GSCORR-shift as GSCORR-task minus GSCORR-rest. GSCORR-tr and trGSCORR-shift were also computed on the task residual time series to quantify the impact of the task-related activity during the trials. To test the secondary aim, brain regions were firstly divided in one cluster showing significant task-related activation and one showing significant deactivation across the three trial conditions. Then, correlations between GSCORR-rest/task/shift and activation/deactivation in the two clusters were computed. As sensitivity analysis, GSCORR-shift was computed on the same sample after performing a global signal regression and GSCORR-rest/task/shift were correlated with the task performance.

RESULTS

Sensory and temporo-parietal regions exhibited a negative GSCORR-shift. Conversely, associative regions (ie. left lingual gyrus, bilateral dorsal posterior cingulate gyrus, cerebellum areas, thalamus, posterolateral parietal cortex) displayed a positive GSCORR-shift (FDR-corrected p < 0.05). GSCORR-shift showed similar patterns to trGSCORR-shift (magnitude increased) and after global signal regression (magnitude decreased). Concerning BOLD changes, Brodmann area 6 and inferior parietal lobule showed activation, while posterior parietal lobule, cuneus, precuneus, middle frontal gyrus showed deactivation (FDR-corrected p < 0.05). No correlations were found between GSCORR-rest/task/shift and beta-coefficients in the activation cluster, although negative correlations were observed between GSCORR-task and GO/STOP-correct deactivation (Pearson rho=-0.299/-0.273; Bonferroni-p < 0.05). Weak associations between GSCORR and task performance were observed (uncorrected p < 0.05).

CONCLUSION

GSCORR state-dependent reconfiguration indicates a reallocation of functional resources to associative areas during stop-signal task. GSCORR, activation and deactivation may represent distinct proxies of brain states with specific neurofunctional relevance.

Proactive and Reactive Inhibitory Control Strategies: Exploring the Impact of Interindividual Variables on an ERP Continuous Performance Task (AX-CPT)

According to the Dual Mechanisms of Control (DMC) framework, cognitive control can be divided into two strategies: proactive cognitive control, which relies mainly on the active maintenance of contextual information relevant to the ongoing task; and reactive cognitive control, which is a form of transient control triggered by an external cue. Although cognitive control has been studied extensively, little is known about the specificities of inhibition within the framework of the DMC model and the influence of interindividual variables on inhibitory control.Thanks to an inhibitory version of the continuous performance task (CPT), we studied behavioral performances and Event-Related Potentials (ERPs) related to proactive and reactive inhibition, and their links to psychological profile and cognitive performances. One hundred and five young adults underwent the task, along with a short clinical and cognitive evaluation.We were able to observe ERPs related to proactive (cue-N1, cue-N2, cue-P3, and the contingent negative variation) and reactive inhibitory control (target-N2 and target-P3). Our results showed that proactive strategies appeared to be linked with impulsivity, working memory abilities, dominant response inhibition, gender, and the consumption pattern of nicotine. Reactive strategies appeared to be linked with attentional and working memories abilities.Overall, the inhibitory AX-CPT allowed a specific investigation of cognitive control within the framework of the DMC based on behavioral and ERP variables. This provided us an opportunity to investigate the principal ERP components related to proactive and reactive inhibitory control strategies as well as to link them with specific clinical and cognitive variables.

Age differences in inhibitory and working memory functioning: limited evidence of system interactions

Debate persists regarding the nature of age-related deficits in inhibition, and whether inhibitory functioning depends on working memory systems. The current research aimed to measure age-related differences in inhibition and working memory, characterize the relationship between inhibitory functions and working memory performance, and determine how these relationships are affected by age. Toward these ends, we measured performance on a range of established paradigms in 60 young adults (18-30 years) and 60 older adults (60-88 years). Our findings support age-related increases in reflexive inhibition (based on the fixation offset effect and inhibition of return) and age-related decrements in volitional inhibition (based on several paradigms: antisaccade, Stroop, flanker, and Simon). This evidence of stronger reflexive inhibition combined with weaker volitional inhibition suggests that age-related deterioration of cortical structures may allow subcortical structures to operate less controlled. Regarding working memory, older adults had lower backward digit scores and lower forward and backward spatial scores. However, of the 32 analyses (16 in each age group) that tested for dependence of inhibitory functioning on working memory functioning, only one (in young adults) indicated that inhibition performance significantly depended on working memory performance. These results indicate that inhibition and working memory function largely independently in both age groups, and age-related working memory difficulties cannot account for age-related declines in inhibitory control.

The effect of tDCS on inhibitory control and its transfer effect on sustained attention in children with autism spectrum disorder: An fNIRS study

BACKGROUND

Individuals with autism spectrum disorder (ASD) have inhibitory control deficits. The combination of transcranial direct current stimulation (tDCS) and inhibitory control training produces good transfer effects and improves neuroplasticity. However, no studies have explored whether applying tDCS over the dlPFC improves inhibitory control and produces transfer effects in children with ASD.

OBJECTIVE

To explore whether multisession tDCS could enhance inhibitory control training (response inhibition), near-transfer (interference control) and far-transfer effects (sustained attention; stability of attention) in children with ASD and the generalizability of training effects in daily life and the class, as reflected by behavioral performance and neural activity measured by functional near-infrared spectroscopy (fNIRS).

METHODS

Twenty-eight autistic children were randomly assigned to either the true or sham tDCS group. The experimental group received bifrontal tDCS stimulation at 1.5 mA, administered for 15 min daily across eight consecutive days. tDCS was delivered during a computerized Go/No-go training task. Behavioral performance in terms of inhibitory control (Dog/Monkey and Day/Night Stroop tasks), sustained attention (Continuous Performance and Cancellation tests), prefrontal cortex (PFC) neural activity and inhibitory control and sustained attention in the class and at home were evaluated.

RESULTS

Training (response inhibition) and transfer effects (interference control; sustained attention) were significantly greater after receiving tDCS during the Go/No-go training task than after receiving sham tDCS. Changes in oxyhemoglobin (HbO) concentrations in the dlPFC and FPA associated with consistent conditions in the Day/Night Stroop and Continuous Performance test were observed after applying tDCS during the inhibitory control training task. Notably, transfer effects can be generalized to classroom environments.

CONCLUSION

Inhibitory control training combined with tDCS may be a promising, safe, and effective method for improving inhibitory control and sustained attention in children with ASD.

Objective Parameters in Attention Deficit Hyperactivity Disorder: Eye and Head Movements

OBJECTIVE

We aimed to evaluate eye and head movements, which are objective parameters in ADHD. Method: While the children were watching the course video task, which included the relevant (teacher and smart board) and irrelevant (any regions outside the relevant area) areas of interest, their eye movements were evaluated through eye tracking, and video recordings were made simultaneous. Head position estimation was made using through video recordings. The proportion of total fixation duration on areas of interest (PFDAOI) and saccade count, amplitude, velocity for eye movements, number of total head movements and angular change of head movement in x-y-z axes for head movements were compared.

RESULTS

Children with ADHD had lower PFDAOI on the relevant area, and had more saccade and head movements The angular change of head movement in the x-axis was higher in the ADHD group.

CONCLUSION

In the assessment of ADHD, the eye and head movements may be particulary useful.

Progressive increase of brain gray matter volume in individuals with regular soccer training

The study aimed to investigate alterations in gray matter volume in individuals undergoing regular soccer training, using high-resolution structural data, while also examining the temporal precedence of such structural alterations. Both voxel-based morphometry and source-based morphometry (SBM) methods were employed to analyze volumetric changes in gray matter between the soccer and control groups. Additionally, a causal network of structural covariance (CaSCN) was built using granger causality analysis on brain structural data ordering by training duration. Significant increases in gray matter volume were observed in the cerebellum in the soccer group. Additionally, the results of the SBM analysis revealed significant increases in gray matter volume in the calcarine and thalamus of the soccer group. The analysis of CaSCN demonstrated that the thalamus had a prominent influence on other brain regions in the soccer group, while the calcarine served as a transitional node, and the cerebellum acted as a prominent node that could be easily influenced by other brain regions. In conclusion, our study identified widely affected regions with increased gray matter volume in individuals with regular soccer training. Furthermore, a temporal precedence relationship among these regions was observed.

The neurocognitive correlates of non-substance addictive behaviors

Neurocognitive deficits have been implicated as transdiagnostic risk markers of substance use disorders. However, these have yet to be comprehensively evaluated in other, non-substance addictions. In a large, general community sample (N = 475) the present study evaluated the neurocognitive correlates of problem alcohol use and three non-substance-related addictive behaviors: addictive eating (AE), problematic pornography use (PPU), and problematic use of the internet (PUI), to identify potential shared and distinct neurocognitive correlates. A sample of Australian residents (54.4 % female M[SD] age = 32.4[11.9] years) completed a comprehensive online assessment of neurocognitive tasks tapping into eight distinct expert-endorsed domains purportedly associated with addiction. Multiple linear regressions with bootstrapping were used to examine associations among each addictive behavior of interest and neurocognition, trait impulsivity, and compulsivity, as well as key covariates. Neurocognition was differentially associated with each addictive behavior. None of the neurocognitive domains were significantly associated with problematic alcohol use or AE (p >.05), poorer performance monitoring was significantly associated with higher levels of PPU and PUI (β = -0.10, p =.049; β = -0.09, p =.028), and a preference for delayed gratification was associated with more severe PUI (β = -0.10, p =.025). Our findings have theoretical implications for how we understand non-substance addiction and suggest the need for a more nuanced approach to studying addictive behaviors that take into account the underlying neurocognitive mechanisms associated with each type of addiction.

Cortical paired associative stimulation shows impaired plasticity of inhibition networks as a function of chronic alcohol use

BACKGROUND

Response inhibition - or the ability to withhold a suboptimal response - relies on the efficacy of fronto-striatal networks, and is impaired in neuropsychiatric disorders including addiction. Cortical paired associative stimulation (cPAS) is a form of transcranial magnetic stimulation (TMS) which can strengthen neuronal connections via spike-timing-dependent plasticity mechanisms. Here, we used cPAS targeting the fronto-striatal inhibitory network to modulate performance on a response inhibition measure in chronic alcohol use.

METHODS

Fifty-five participants (20 patients with a formal alcohol use disorder (AUD) diagnosis (26-74 years, 6[30%] females) and 20 matched healthy controls (HCs) (27-73 years, 6[30%] females) within a larger sample of 35 HCs (23-84 years, 11[31.4%] females) underwent two randomized sessions of cPAS 1-week apart: right inferior frontal cortex stimulation preceding right presupplementary motor area stimulation by either 4 ms (excitation condition) or 100 ms (control condition), and were subsequently administered the Stop Signal Task (SST) in both sessions.

RESULTS

HCs showed decreased stop signal reaction time in the excitation condition (t(19) = -3.01, p = 0.007, [CIs]:-35.6 to -6.42); this facilitatory effect was not observed for AUD (F(1,31) = 9.57, p = 0.004, CIs: -68.64 to -14.11). Individually, rates of SST improvement were substantially higher for healthy (72%) relative to AUD (13.6%) groups (OR: 2.33, p = 0.006, CIs:-3.34 to -0.55).

CONCLUSION

In line with previous findings, cPAS improved response inhibition in healthy adults by strengthening the fronto-striatal network through putative long-term potentiation-like plasticity mechanisms. Furthermore, we identified a possible marker of impaired cortical excitability, and, thus, diminished capacity for cPAS-induced neuroplasticity in AUD with direct implications to a disorder-relevant cognitive process.

Theta oscillations within right dorsolateral prefrontal cortex contribute differently to speech versus limb inhibition

Evidence suggests that speech and limb movement inhibition are subserved by common neural mechanisms, particularly within the right prefrontal cortex. In a recent study, we found that cathodal stimulation of right dorsolateral prefrontal cortex (rDLPFC) differentially modulated P3 event-related potentials for speech versus limb inhibition. In the present study, we further analyzed these data to examine the effects of cathodal high-definition transcranial direct current stimulation (HD-tDCS) over rDLPFC on frontal theta - an oscillatory marker of cognitive control - in response to speech and limb inhibition, during a Go/No-Go task in 21 neurotypical adults. Electroencephalography data demonstrated that both speech and limb No-Go elicited prominent theta activity over right prefrontal electrodes, with stronger activity for speech compared to limb. Moreover, we found that cathodal stimulation significantly increased theta power over right prefrontal electrodes for speech versus limb No-Go. Source analysis revealed that cathodal, but not sham, stimulation increased theta activity within rDLPFC and bilateral premotor cortex for speech No-Go compared to limb movement inhibition. These findings complement our previous report and suggest (1) right prefrontal theta activity is an amodal oscillatory mechanism supporting speech and limb inhibition, (2) larger theta activity in prefrontal electrodes for speech versus limb following cathodal stimulation may reflect allocation of additional neural resources for a more complex motor task, such as speech compared to limb movement. These findings have translational implications for conditions such as Parkinson's disease, wherein both speech and limb movement are impaired.

Cognitive and motor impulsivity in the healthy brain, and implications for eating disorders and obesity: A coordinate-based meta-analysis and systematic review

Alterations in the impulse-control balance, and in its neural bases, have been reported in obesity and eating disorders (EDs). Neuroimaging studies suggest a role of fronto-parietal networks in impulsive behaviour, with evaluation and anticipatory processes additionally recruiting meso-limbic regions. However, whether distinct facets of cognitive and motor impulsivity involve common vs. specific neural correlates remains unclear. We addressed this issue through Activation Likelihood Estimation (ALE) meta-analyses of fMRI studies on delay discounting (DD) and go/no-go (GNG) tasks, alongside conjunction and subtraction analyses. We also performed systematic reviews of neuroimaging studies using the same tasks in individuals with obesity or EDs. ALE results showed consistent activations in the striatum, anterior/posterior cingulate cortex, medial/left superior frontal gyrus and left supramarginal gyrus for impulsive choices in DD, while GNG tasks elicited mainly right-lateralized fronto-parietal activations. Conjunction and subtraction analyses showed: i) common bilateral responses in the caudate nucleus; ii) DD-specific responses in the ventral striatum, anterior/posterior cingulate cortex, left supramarginal and medial frontal gyri; iii) GNG-specific activations in the right inferior parietal cortex. Altered fronto-lateral responses to both tasks are suggestive of dysfunctional cortico-striatal balance in obesity and EDs, but these findings are controversial due to the limited number of studies directly comparing patients and controls. Overall, we found evidence for distinctive neural correlates of the motor and cognitive facets of impulsivity: the right inferior parietal lobe underpins action inhibition, whereas fronto-striatal regions and the left supramarginal gyrus are related to impulsive decision-making. While showing that further research on clinical samples is required to better characterize the neural bases of their behavioural changes, these findings help refining neurocognitive model of impulsivity and highlight potential translational implications for EDs and obesity treatment.

Response inhibition impairment related to altered frontal-striatal functional connectivity in insomnia disorder: A pilot and non-clinical study

BACKGROUND

It is not clear whether and how insomnia disorder (ID) impairs response inhibition ability. Fronto-striatal functional connectivity (FC) plays a critical role in response inhibition and is found be abnormal in patients with ID. In this study, we examined whether insomnia symptoms impair response inhibition in a large non-clinical sample and whether impaired response inhibition is related to abnormal fronto-striatal FC.

METHODS

One hundred and fifteen young ID patients and 160 age and sex-matched healthy controls (HC) underwent resting-state functional magnetic response imaging scans and performed the stop-signal task (SST). Performance of SST, Gray Matter Volumes (GMVs), and connections of brain regions related to fronto-striatal circuits was compared between groups. Further examined the association between response inhibition impairment and fronto-striatal FC.

RESULTS

The behavioral results showed that patients with ID had significantly longer stop-signal reaction time (SSRT) compared with the HC, reflecting the impaired response inhibition among IDs. Brain imaging results showed IDs had decreased GMVs of the Right Superior Frontal (SFG) and left Supplementary Motor area (SMA). Seed-based FC results showed that compared to HC, the ID showed decreased FC between left SMA and left Paracentral lobule, left SMA and right SMA, and right SFG and right Orbital Middle Frontal gyrus, and increased FC between right SFG and right putamen. Meanwhile, the FC between right SFG and putamen was positively correlated with SSRT in IDs.

CONCLUSIONS

The current study found significantly impaired response inhibition among ID and this impairment may be related to abnormal fronto-striatal FC in ID.

White matter tracts and executive functions: a review of causal and correlation evidence

Executive functions are high-level cognitive processes involving abilities such as working memory/updating, set-shifting and inhibition. These complex cognitive functions are enabled by interactions among widely distributed cognitive networks, supported by white matter tracts. Executive impairment is frequent in neurological conditions affecting white matter; however, whether specific tracts are crucial for normal executive functions is unclear. We review causal and correlation evidence from studies that used direct electrical stimulation during awake surgery for gliomas, voxel-based and tract-based lesion-symptom mapping, and diffusion tensor imaging to explore associations between the integrity of white matter tracts and executive functions in healthy and impaired adults. The corpus callosum was consistently associated with all executive processes, notably its anterior segments. Both causal and correlation evidence showed prominent support of the superior longitudinal fasciculus to executive functions, notably to working memory. More specifically, strong evidence suggested that the second branch of the superior longitudinal fasciculus is crucial for all executive functions, especially for flexibility. Global results showed left lateralization for verbal tasks and right lateralization for executive tasks with visual demands. The frontal aslant tract potentially supports executive functions, however, additional evidence is needed to clarify whether its involvement in executive tasks goes beyond the control of language. Converging evidence indicates that a right-lateralized network of tracts connecting cortical and subcortical grey matter regions supports the performance of tasks assessing response inhibition, some suggesting a role for the right anterior thalamic radiation. Finally, correlation evidence suggests a role for the cingulum bundle in executive functions, especially in tasks assessing inhibition. We discuss these findings in light of current knowledge about the functional role of these tracts, descriptions of the brain networks supporting executive functions and clinical implications for individuals with brain tumours.

Reduced recruitment of inhibitory control regions in very young children with ADHD during a modified Kiddie Continuous Performance Task: a fMRI study

Attention-Deficit/Hyperactivity Disorder (ADHD) symptom profiles are known to undergo changes throughout development, rendering the neurobiological assessment of ADHD challenging across different developmental stages. Particularly in young children (ages 4 to 7 years), measuring inhibitory control network activity in the brain has been a formidable task due to the lack of child-friendly functional Magnetic Resonance Imaging (fMRI) paradigms. This study aims to address these difficulties by focusing on measuring inhibitory control in very young children within the MRI environment. A total of 56 children diagnosed with ADHD and 78 typically developing (TD) 4-7-year-old children were examined using a modified version of the Kiddie-Continuous Performance Test (K-CPT) during BOLD fMRI to assess inhibitory control. We concurrently evaluated their performance on the established and standardized K-CPT outside the MRI scanner. Our findings suggest that the modified K-CPT effectively elicited robust and expected brain activity related to inhibitory control in both groups. Comparisons between the two groups revealed subtle differences in brain activity, primarily observed in regions associated with inhibitory control, such as the inferior frontal gyrus, anterior insula, dorsal striatum, medial pre-supplementary motor area (pre-SMA), and cingulate cortex. Notably, increased activity in the right anterior insula was associated with improved response time (RT) and reduced RT variability on the K-CPT administered outside the MRI environment, although this did not survive statistical correction for multiple comparisons. In conclusion, our study successfully overcame the challenges of measuring inhibitory control in very young children within the MRI environment by utilizing a modified K-CPT during BOLD fMRI. These findings shed light on the neurobiological correlates of inhibitory control in ADHD and TD children, provide valuable insights for understanding ADHD across development, and potentially inform ADHD diagnosis and intervention strategies. The research also highlights remaining challenges with task fMRI in very young clinical samples.

The severity of addiction mediates loneliness and cortical volume in internet gaming disorder

Internet gaming disorder (IGD) subjects reported higher loneliness scores than healthy controls. However, the neural correlates underlying the association between loneliness and IGD remain unclear. Thus, the aim of this study was to explore the relationship between loneliness, online gaming addiction and brain structure. In the current study, structural MRI data were acquired from 84 IGD subjects and 103 matched recreational game users (RGUs). We assessed and compared their addiction severity, loneliness scores, and cortical volumes and analyzed the correlations among these values. Significant correlations were found between loneliness scores and brain volumes in the postcentral cortex, the medial orbitofrontal cortex, the rostral anterior cingulate cortex, and the temporal cortex. In addition, the addiction severity scores partly mediated the relationship between loneliness score and cortical volume in IGD. The results showed that participants with extreme loneliness had significant correlations with brain regions responsible for executive control, social threat surveillance and avoidance. More importantly, the severity of addiction mediates loneliness and cortical volume. The findings shed new insight into the neural mechanisms of loneliness and IGD and have implications for potential treatment.

The Ability to Voluntarily Regulate Theta Band Activity Affects How Pharmacological Manipulation of the Catecholaminergic System Impacts Cognitive Control

BACKGROUND

The catecholaminergic system influences response inhibition, but the magnitude of the impact of catecholaminergic manipulation is heterogeneous. Theoretical considerations suggest that the voluntary modulability of theta band activity can explain this variance. The study aimed to investigate to what extent interindividual differences in catecholaminergic effects on response inhibition depend on voluntary theta band activity modulation.

METHODS

A total of 67 healthy adults were tested in a randomized, double-blind, cross-over study design. At each appointment, they received a single dose of methylphenidate or placebo and performed a Go/Nogo task with stimuli of varying complexity. Before the first appointment, the individual's ability to modulate theta band activity was measured. Recorded EEG data were analyzed using temporal decomposition and multivariate pattern analysis.

RESULTS

Methylphenidate effects and voluntary modulability of theta band activity showed an interactive effect on the false alarm rates of the different Nogo conditions. The multivariate pattern analysis revealed that methylphenidate effects interacted with voluntary modulability of theta band activity at a stimulus processing level, whereas during response selection methylphenidate effects interacted with the complexity of the Nogo condition.

CONCLUSIONS

The findings reveal that the individual's theta band modulability affects the responsiveness of an individual's catecholaminergic system to pharmacological modulation. Thus, the impact of pharmacological manipulation of the catecholaminergic system on cognitive control most likely depends on the existing ability to self-modulate relevant brain oscillatory patterns underlying the cognitive processes being targeted by pharmacological modulations.

Neural underpinnings of response inhibition in substance use disorders: weak meta-analytic evidence for a widely used construct

RATIONALE

Substance use disorders (SUDs) rank among the most severely debilitating psychiatric conditions. Among others, decreased response inhibition capacities could make it more difficult for patients to abstain from drug use and maintain abstinence. However, meta-analyses on the neural basis of response inhibition in SUDs yielded conflicting results.

OBJECTIVE

In this study, we revisited the neuroimaging research field and summarized the existing fMRI literature on overt response inhibition (Go/NoGo and stop-signal paradigms) across different SUDs.

METHODS

We performed a systematic literature review and an activation likelihood estimation (ALE) meta-analysis to investigate the actual convergence of functional deviations observed in SUD samples. Results were further supplied by consecutive robustness measures and a post-hoc random-effects meta-analysis of behavioural data.

RESULTS

We identified k = 21 eligible studies for our analysis. The ALE analysis indicated a significant cluster of convergence with its statistical peak in the right anterior insula. Consecutive analyses, however, indicated this result was not robust and susceptible towards publication bias. Additionally, a post-hoc random effects meta-analysis of the behavioural parameters of Go/NoGo and stop-signal paradigms reported by the included studies revealed no significant differences in task performance comparing SUD samples and controls.

CONCLUSION

We discuss that the role of task-based response inhibition may require some refinement as an overarching marker for SUD pathology. Finally, we give a few prospects for future research that should be further explored in this context.

Biomarkers for Cognitive Control, Response Inhibition, Aggressivity, Impulsivity, and Violence

Deficits in cognitive control contribute to behavioral impairments across neuropsychiatric disorders. Cognitive control is captured as a construct in the Research Domain Construct (RDoC) matrix and incorporate subdomains of goal selection, response selection, and performance monitoring. Relevant tasks for these subdomains include the "AX" version of the continuous performance task (goal selection) and the Go/NoGo and Stop-Signal reaction time tasks (response selection). Underlying mechanisms for these domains have been investigated intensively using fMRI and event-related potential (ERP) approaches, which provide candidate biomarkers for translational research. In RDoC, impulsive behaviors are provisionally assigned to the cognitive control/response selection construct, but other factors may also contribute. Impulsivity has gained increased importance over recent years due to its link to aggression and suicidality, which is mediated especially through the constructs of urgency and frustrative nonreward. These constructs, in turn, may be captured through scales such as the Urgency, (Lack of) Premeditation, (Lack of) Perseverance, and Sensation Seeking (UPPS-P) impulsivity scale and the Point Subtraction Aggression Paradigm (PSAP), respectively. At present, no validated biomarkers exist for either urgency or aggressivity. Potential directions for the development of predictive biomarkers for both targets are discussed.

Inhibitory control in children with agenesis of the corpus callosum compared with typically developing children

OBJECTIVES

The developmental absence (agenesis) of the corpus callosum (AgCC) is a congenital brain malformation associated with risk for a range of neuropsychological difficulties. Inhibitory control outcomes, including interference control and response inhibition, in children with AgCC are unclear. This study examined interference control and response inhibition: 1) in children with AgCC compared with typically developing (TD) children, 2) in children with different anatomical features of AgCC (complete vs. partial, isolated vs. complex), and 3) associations with white matter volume and microstructure of the anterior (AC) and posterior commissures (PC) and any remnant corpus callosum (CC).

METHODS

Participants were 27 children with AgCC and 32 TD children 8-16 years who completed inhibitory control assessments and brain MRI to define AgCC anatomical features and measure white matter volume and microstructure.

RESULTS

The AgCC cohort had poorer performance and higher rates of below average performance on inhibitory control measures than TD children. Children with complex AgCC had poorer response inhibition performance than children with isolated AgCC. While not statistically significant, there were select medium to large effect sizes for better inhibitory control associated with greater volume and microstructure of the AC and PC, and with reduced volume and microstructure of the remnant CC in partial AgCC.

CONCLUSIONS

This study provides evidence of inhibitory control difficulties in children with AgCC. While the sample was small, the study found preliminary evidence that the AC (f2=.18) and PC (f2=.30) may play a compensatory role for inhibitory control outcomes in the absence of the CC.

Failing to attend versus failing to stop: Single-trial decomposition of action-stopping in the stop signal task

The capacity to stop impending or ongoing actions contributes to executive control over behavior. Action-stopping, however, is difficult to directly quantify. It is therefore assayed via computational modeling of behavior in the stop signal task to estimate the latency of stopping (stop signal reaction time, SSRT) and, more recently, the reliability of stopping in terms of the distribution of SSRTs (standard deviation, SD-SSRT) and the frequency with which one outright fails to react to a stop signal (trigger failures, TF). Critically, the validity of computational estimates remains unknown because we currently have no direct readouts of behavior against which to compare them. Here, we developed a method for providing single-trial behavioral readouts of SSRT and trigger failures. The method relies on an adaptation of the stop signal task in which participants respond by moving a computer mouse. In two online experiments, we used movement kinematics to quantify stopping performance (SSRT, SD-SSRT, and TF), and then applied the standard Race Model and recent BEESTS model in order to examine the convergent validity of the methods. Overall, we demonstrate good correspondence between kinematics- and model-based estimates of stopping performance at the group and individual level. We conclude that the new method provides valid estimates of stopping performance that, unlike model-based estimates, can be read out at the level of single trials. Our approach might therefore be useful for interrogating single-trial neurophysiological correlates of stopping and for large-scale, online studies of behavioral stopping.

Effect of Cognitive Rehabilitation by Auditory Stroop Training on Quality of Life of Individuals with Tinnitus

Background: Studies have shown that tinnitus patients have difficulties in cognitive function such as memory and attention. The Stroop task engages the attention network where one aspect of the stimulus is noticed while the other one is ignored. Thus, Stroop training can improve the patient's cognitive control and ability to ignore the tinnitus signal. Method: Thirty chronic tinnitus (> 6 months) patients were included in this study. They were distributed into two 15-member groups: intervention and control. Common audiometric, psychometric, and psychoacoustic evaluations of tinnitus were performed for two groups before intervention and after auditory Stroop training of group 1. Results: There was significant difference in the quality of life and THI scores, VAS of annoyance, and reaction time of Stroop task before and after intervention in group1. The decreased reaction time was positively correlated with improved quality of life, THI score, and VAS of annoyance. Conclusion: Cognitive rehabilitation using tasks such as auditory Stroop can be effective in controlling tinnitus by improving cognitive control.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12070-023-04011-w.

Effects of transcranial direct current stimulation over human motor cortex on cognitive-motor and sensory-motor functions

The primary motor cortex (M1) is broadly acknowledged for its crucial role in executing voluntary movements. Yet, its contributions to cognitive and sensory functions remain largely unexplored. Transcranial direct current stimulation (tDCS) is a noninvasive neurostimulation method that can modify brain activity, thereby enabling the establishment of a causal link between M1 activity and behavior. This study aimed to investigate the online effects of tDCS over M1 on cognitive-motor and sensory-motor functions. Sixty-four healthy participants underwent either anodal or sham tDCS while concurrently performing a set of standardized robotic tasks. These tasks provided sensitive and objective assessments of brain functions, including action selection, inhibitory control, cognitive control of visuomotor skills, proprioceptive sense, and bimanual coordination. Our results revealed that anodal tDCS applied to M1 enhances decision-making capacity in selecting appropriate motor actions and avoiding distractors compared to sham stimulation, suggesting improved action selection and inhibitory control capabilities. Furthermore, anodal tDCS reduces the movement time required to accomplish bimanual movements, suggesting enhanced bimanual performance. However, we found no impact of anodal tDCS on cognitive control of visuomotor skills and proprioceptive sense. This study suggests that augmenting M1 activity via anodal tDCS influences cognitive-motor and sensory-motor functions in a task-dependent manner.

Long-term exposure to high altitude reduces alpha and beta bands event-related desynchronization in a Go/NoGo task

More than 80 million people worldwide permanently live at high altitudes, and living in such a hypoxic environment can impair cognitive functions. However, it is largely unknown how long-term exposure to high altitude affects neural oscillations underlying these cognitive functions. The present study employed a Go/NoGo task to investigate the effects of long-term exposure to high altitude on neural oscillations during cognitive control. We compared event-related spectral perturbations between the low-altitude and high-altitude groups, and the results revealed increased theta event-related synchronization (ERS) and decreased alpha and beta event-related desynchronizations (ERDs) during the NoGo condition compared to the Go condition. Importantly, the high-altitude group showed reduced alpha and beta ERDs compared to the low-altitude group, while the theta ERS was not affected by altitude. We suggest that long-term exposure to high altitude has an impact on top-down inhibitory control and movement preparation and execution in the Go/NoGo task.

Computational mechanism underlying switching of motor actions

Surviving in a constantly changing environment requires not only the ability to select actions, but also the flexibility to stop and switch actions when necessary. Extensive research has been devoted to understanding how the brain switches actions, yet the computations underlying switching and how it relates to selecting and stopping processes remain elusive. A central question is whether switching is an extension of the stopping process or involves different mechanisms. To address this question, we modeled action regulation tasks with a neurocomputational theory and evaluated its predictions on individuals performing reaches in a dynamic environment. Our findings suggest that, unlike stopping, switching does not necessitate a proactive pause mechanism to delay movement onset. However, switching engages a pause mechanism after movement onset, if the new target location is unknown prior to switch signal. These findings offer a new understanding of the action-switching computations, opening new avenues for future neurophysiological investigations.