Stop-signal Task Research Articles

A unified account of simple and response-selective inhibition

Response inhibition is a key attribute of human executive control. Standard stop-signal tasks require countermanding a single response; the speed at which that response can be inhibited indexes the efficacy of the inhibitory control networks. However, more complex stopping tasks, where one or more components of a multi-component action are cancelled (i.e., response-selective stopping) cannot be explained by the independent-race model appropriate for the simple task (Logan and Cowan 1984). Healthy human participants (n=28; 10 male; 19–40 years) completed a response-selective stopping task where a ‘go’ stimulus required simultaneous (bimanual) button presses in response to left and right pointing green arrows. On a subset of trials (30%) one, or both, arrows turned red (constituting the stop signal) requiring that only the button-press(es) associated with red arrows be cancelled. Electromyographic recordings from both index fingers (first dorsal interosseous) permitted the assessment of both voluntary motor responses that resulted in overt button presses, and activity that was cancelled prior to an overt response (i.e., partial, or covert, responses). We propose a simultaneously inhibit and start (SIS) model that extends the independent race model and provides a highly accurate account of response-selective stopping data. Together with fine-grained EMG analysis, our model-based analysis offers converging evidence that the selective-stop signal simultaneously triggers a process that stops the bimanual response and triggers a new unimanual response corresponding to the green arrow. Our results require a reconceptualisation of response-selective stopping and offer a tractable framework for assessing such tasks in healthy and patient populations.Significance StatementResponse inhibition is a key attribute of human executive control, frequently investigated using the stop-signal task. After initiating a motor response to a go signal, a stop signal occasionally appears at a delay, requiring cancellation of the response. This has been conceptualised as a ‘race’ between the go and stop processes, with the successful (or failed) cancellation determined by which process wins the race. Here we provide a novel computational model for a complex variation of the stop-signal task, where only one component of a multicomponent action needs to be cancelled. We provide compelling muscle activation data that support our model, providing a robust and plausible framework for studying these complex inhibition tasks in both healthy and pathological cohorts.

Impulsivity across psychiatric disorders in young adults

PurposeImpulsivity is a common cognitive issue across several psychiatric illnesses but is most frequently associated with the DSM-5 Disruptive, Impulse Control and Conduct Disorders, ADHD, and addictive disorders. We hypothesized that a wide range of psychiatric disorders would be associated with elevated impulsivity, not just those commonly linked to impulsiveness. This study aimed to explore the relationship between impulsivity and various psychiatric disorders in young adults. Procedures700 non-treatment seeking participants (aged 18–29 years) were enrolled from the general community, provided demographic information, and underwent a psychiatric evaluation to screen for various psychiatric disorders. Each participant then completed the Barratt Impulsiveness Scale (BIS), a self-report measure of impulsivity, followed by the Stop Signal Task (SST), a computerized stop-attention task that measures impulse control. Impulsivity levels across psychiatric disorders were examined by analyzing z-scores relative to controls. Main findingsPatients with bulimia nervosa, comorbid panic disorder with agoraphobia, and borderline personality disorder showed the highest levels of attentional, motor, and non-planning impulsivity, respectively. The effect size of the difference in total BIS impulsivity was large (d > 0.8) for several conditions including eating, personality, addictive, and mood disorders. The effect size of the difference in impulsivity was not large for any of the measures of ADHD. As compared to other psychiatric disorders analyzed, trichotillomania showed the greatest levels of impulsivity as measured by SST. Principal conclusionsThis data indicates that a wide range of psychiatric disorders exhibit heightened impulsivity with findings differing across various cognitive domains. Comorbidity resulted in unique findings of elevated impulsivity. This may suggest utility in viewing impulsivity as a transdiagnostic factor for a broad range of psychiatric disorders. Future studies should analyze comorbidities and whether patient psychiatric medication impacts these findings.

Pharmacological and Psychological Treatment Have Common and Specific Effects on Brain Activity in Obsessive-Compulsive Disorder

Initial treatment for obsessive-compulsive disorder (OCD) consists of pharmacological treatment with selective serotonin reuptake inhibitors (SSRIs) and/or psychological treatment with cognitive behavioral therapy (CBT). The assumption is that both treatments have different neural working mechanisms, but empirical evidence is lacking. We investigated whether these treatments induce similar or different functional neural changes in OCD. We conducted a longitudinal nonrandomized controlled trial in which thirty-four OCD patients were treated with sixteen weeks of CBT or SSRIs. Functional magnetic resonance imaging was performed before and after treatment during emotional processing (emotional face matching and symptom provocation tasks) and response inhibition (stop signal task). Twenty matched healthy controls were scanned twice with a similar time interval. Both CBT and SSRIs were successful in reducing OCD symptoms. Compared to healthy controls, treatment led to a reduction of insula activity in OCD patients during symptom provocation. The comparison between treatment groups revealed widespread divergent brain changes in the cerebellum, posterior insula, caudate nucleus, hippocampus, and occipital and prefrontal cortex during all tasks, explained by relative increases of activity following CBT compared to relative decreases of activity following SSRIs. Pharmacological and psychological treatment primarily lead to opposite changes in brain function, with a common reduction of insula activity during symptom provocation. These findings provide insight into common and specific neural mechanisms underlying treatment response, suggesting that CBT and SSRIs support recovery from OCD along partly distinct pathways. This trial is registered with NTR6575.

Effect of Preadolescents' Obesity on Inhibitory Control During Stop-Signal Task: A Functional EEG Network Study.

Objectives. Until now, limited knowledge remains regarding the association among childhood obesity, cognitive behavior, and brain networks. Utilizing a publicly available dataset, we aimed to investigate the relationships between childhood obesity and functional networks during the stop-signal task. Results. Given the huge conflict-monitoring and inhibitory control demands of the task, both enhanced network connectivity and properties were observed under the "No-go" compared to the "Go" condition for both obese and non-obese preadolescents. Obese preadolescents exhibited significantly increased frontal-parietal, frontal-occipital, and frontal-temporal linkages, as well as heightened network efficiency under both "Go" and "No-go" conditions compared to non-obese counterparts. Additionally, significant correlations were found between network connectivity and properties and preadolescents' body mass index (BMI), with their combination predicting BMI scores successfully. Conclusions. These findings support that childhood obesity is not simply a deviant habit with restricted physical health consequences, but rather associated with the atypical development of frontal-based networks involved in inhibitory control and cognitive performance.

Inhibitory deficits in Klinefelter syndrome are secondary to deficits in the auditory and motor domain

Deficits in several cognitive domains are prevalent in men with Klinefelter Syndrome (KS). Verbal deficits are among the most characteristic cognitive impairments of KS, yet other cognitive domains also exhibit deficits. Executive functions, especially working memory capacity and inhibitory control, are frequently affected as well. A common limitation of previous studies addressing potential deficits in inhibitory control is their potential conflation with language-related capabilities, as for example is the case with the Stroop task. Importantly, none of the prior studies utilized the best-accepted approach to study inhibition, namely the Stop Signal Task (SST). This study therefore tested for deficits in inhibitory control in individuals with KS and controls (HC) using a version of the SST with non-semantic auditory stimuli. In addition to the classic behavioral performance measures (e.g., the go reaction time, stopping accuracy, or stop signal reaction time), we also derived parameters of inhibition and attention from electromyography (EMG), electroencephalography (EEG), and Bayesian modeling. Men with KS exhibited prolonged stopping latencies (i.e., stop signal reaction times) and reduced stopping accuracies. Yet, whereas these model-based indices were indicative of attenuated inhibitory control, neither event-related brain potentials nor an EMG-measure of the stopping latency confirmed such deficits. Behavioral and EEG indices, however, provided evidence for deficits in motor response preparation and generation, as well as the early processing of auditory stimuli. In sum, the overall pattern of results does not support the existence of inhibitory deficits in KS per se, but rather suggests that behavioral indices of impaired inhibition may result from early low-level deficits in the auditory and motor domains, as well as a differential weighting in the processing of different aspects of the task.

Mindfulness and inhibitory control: Insights from the stop signal task with neutral and reward-associated stimuli.

Mindfulness has been linked to enhanced inhibitory control, yet the dynamics of this relationship, especially in reward situations, are not well understood. Our cross-sectional study aimed to explore the relationship between trait mindfulness and a performance measure of inhibitory control as a function of reward context operationalized by stimuli characteristics, and temporal inhibitory demands. Thirty-six individuals aged 19 to 41 filled out the Mindful Attention Awareness Scale (MAAS) and performed a stop signal task (SST), that included both neutral (stone images) and reward-related (money images) stimuli. The SST encompassed four conditions: neutral go/neutral stop, neutral go/reward stop, reward go/neutral stop, and reward go/reward stop, requiring participants to suppress reactions either during or after encountering reward-related stimuli. The relevant index of inhibitory control is the stop signal reaction time (SSRT), a performance measure of inhibitory control. Our findings showed no notable variation in the relationship between the MAAS score and SSRT across the different conditions. However, there was an overall significant effect of MAAS score on SSRT, irrespective of condition. Results may reflect the benefit of mindfulness on inhibitory control after generalized reward exposure.

Association between impulsivity and depressive symptoms in recently detoxified patients with alcohol dependence

Background: Depression and impulsivity are etiologically linked to alcohol dependence (AD) and are known to affect course and outcomes. The relationship between impulsivity and depressive symptoms has been investigated only in a few studies of individuals with AD. Aim: This study aimed to explore the association between impulsivity and depressive symptoms in patients with AD. Materials and Methods: Our study was conducted in the inpatient setup of a tertiary care psychiatry institute. The study design is cross-sectional. The Barratt Impulsiveness Scale (BIS-11) and stop signal task (SST) were used to assess levels of global impulsivity and behavioral impulsivity, respectively, among 60 recently detoxified inpatients with AD. The Hamilton Depression Rating Scale (HAM-D) was used to measure depressive symptoms. The results were analyzed to examine the association of depressive symptoms with impulsivity. Pearson’s coefficient of correlation or Spearman’s rank correlation and linear regression analysis were performed to explore the association between quantitative variables. Results: Patients with higher HAM-D scores were found to have significantly higher score on all three subscales of the BIS-11. The attention impulsivity subscale had the strongest correlations (r = 0.53, P < 0.001). Depressive symptoms were more strongly correlated with cognitive impulsivity (r = 0.54, P< 0.0001) compared with motor impulsivity and were not significantly associated with behavioral impulsivity. Adjusting for other variables, cognitive impulsivity was found to be the strongest predictor of the severity of depressive symptoms. Conclusions: The study showed a strong association between impulsivity and depressive symptoms in individuals with AD. This relationship may apply more to cognitive impulsivity, reflecting the role of impulsive decisions compared with impulsive actions.

Midfrontal conflict theta and parietal P300 are linked to a latent factor of DSM externalising disorders.

Psychiatric illnesses form spectra rather than categories, with symptoms varying continuously across individuals, i.e., there is no clear break between health and disorder. Dimensional measures of behaviour and brain activity are promising targets for studying biological mechanisms that are common across disorders. Here, we assessed the extent to which neural measures of the sensitivity of the three biological systems in the reinforcement sensitivity theory (RST) could account for individual differences in a latent general factor estimated from symptom counts across externalising disorders (EXTs). RST explanatory power was pitted against reduced P300, a reliable indicator of externalising per previous research. We assessed 206 participants for DSM-5 EXTs (antisocial personality disorder, conduct disorder, attention-deficit/hyperactivity disorder, intermittent explosive disorder symptoms, alcohol use disorder, and cannabis use disorder). Of the final sample, 49% met diagnostic criteria for at least one of the EXTs. Electroencephalographic measures of the sensitivities of the behavioural activation system (BAS), the fight/flight/freeze system, and the behavioural inhibition system (BIS), as well as P300 were extracted from the gold bar-lemon and stop-signal tasks. As predicted, we found that low neural BIS sensitivity and low P300 were uniquely and negatively associated with our latent factor of externalising. Contrary to prediction, neural BAS/"dopamine" sensitivity was not associated with externalising. Our results provide empirical support for low BIS sensitivity and P300 as neural mechanisms common to disorders within the externalising spectrum; but, given the low N involved, future studies should seek to assess the replicability of our findings and, in particular, the differential involvement of the three RST systems.

Comparative Effects of Cognitive Rehabilitation and Photobiomodulation on Drug Craving in Treatment-Seeking Opioid Addicts.

Background: Drug addiction refers to a maladaptive pattern of drug use that frequently leads to substance abuse problems and accompanying cognitive and behavioral symptoms. Among the crucial criteria of drug addiction, craving stands out as a potent factor contributing to ongoing drug abuse and relapse following period of abstinence. To date, there is no definitive method for eradicating opioid cravings. The introduction of novel neurocognitive interventions, such as cognitive rehabilitation and photobiomodulation (PBM), into the realm of psychiatric treatments holds promise due to the parallels between drug addiction and other psychiatric disorders. These innovative techniques offer potential value in addressing drug addiction. Objective: This study aimed to assess and compare the efficacy of cognitive rehabilitation and PBM in alleviating drug cravings among individuals undergoing addiction treatment in clinical settings. Methods: The research used randomized clinical trial as the chosen research method. The statistical population encompassed all clients receiving treatment for addiction at clinics, selected through the convenience sampling method, with α = 0.05 significance level and an effect size of 85%. Gpower software was utilized to determine three equal groups. Sixty-three participants, each having a mean total score higher than 3 out of 5 on the Desire for Drug Questionnaire (DDQ), were randomly assigned to two experimental groups (n = 21 each) and a control group (n = 21). For the assessment of immediate and periodic opioid craving, the DDQ and the Obsessive Compulsive Drug Use Scale were used. In the low-level laser group, an 810 nm wavelength with continuous irradiation was applied twice a week at a distance of 1 cm by 1 cm to the prefrontal part of the brain for duration of 6 weeks (12 sessions). In the brain rehabilitation group, the stop signal and n-back tasks software were used twice a week for period of 6 weeks (comprising 12 sessions, each lasting 30 min). Results: The results demonstrated that each intervention significantly reduced drug craving in both the post-test and follow-up phases compared to the control group. The Bonferroni post hoc test indicated that PBM was more effective than cognitive rehabilitation in terms of working memory (WM) and inhibitory control for reducing drug craving (p < 0.05). Conclusions: While both PBM and cognitive rehabilitation targeting WM and inhibitory control effectively reduced opioid drug craving, low-level laser therapy proved to be more effective than cognitive rehabilitation in this regard.

Midfrontal theta reactivity to conflict and error are linked to externalizing and internalizing respectively.

Dimensional psychopathology scores measure symptom severity; cutting across disorder categories. Their clinical utility is high given comorbidity, but their neural basis is unclear. We used scalp electroencephalography (EEG) to concurrently assess neural activity across internalizing and externalizing traits. "Theta rhythm" (4-7Hz) spectral power at the frontal midline site Fz in specific goal conflict and action error phases within a trial of a Stop-Signal Task was extracted using process-specific contrasts. A final sample of 146 community participants (63 males, 83 females; mean age = 36; SD = 9; range = 18 - 56), oversampled for externalizing disorder (49% diagnosed with a DSM-5 externalizing disorder), also supplied psychopathology and personality data. We used the Minnesota Multiphasic Personality Inventory-3 (MMPI-3) to measure symptoms and traits of psychopathology. An MMPI-3 measure of the higher-order internalizing psychopathology spectrum was positively correlated with action error theta. An MMPI-3 measure of the higher-order spectrum of externalizing psychopathology was negatively correlated with goal-conflict theta. We showed that goal-conflict and error theta activity are higher-order processes that index psychopathology severity. The associations extend into the nominally healthy range, and so reflect theta-related factors that apply to the general population as well as patients with sub-threshold diagnoses.

Effects of dopaminergic treatment on inhibitory control differ across Hoehn and Yahr stages of Parkinson's disease.

Motor inhibitory control, a core component of cognitive control, is impaired in Parkinson's disease, dramatically impacting patients' abilities to implement goal-oriented adaptive strategies. A progressive loss of the midbrain's dopamine neurons characterizes Parkinson's disease and causes motor features responsive to dopaminergic treatments. Although such treatments restore motor symptoms, their impact on response inhibition is controversial. Most studies failed to show any effect of dopaminergic medicaments, although three studies found that these drugs selectively improved inhibitory control in early-stage patients. Importantly, all previous studies assessed only one domain of motor inhibition, i.e. reactive inhibition (the ability to react to a stop signal). The other domain, i.e. proactive inhibition (the ability to modulate reactive inhibition pre-emptively according to the current context), was utterly neglected. To re-examine this issue, we recruited cognitively unimpaired Parkinson's patients under dopaminergic treatment in the early (Hoehn and Yahr, 1-1.5, n = 20), intermediate (Hoehn and Yahr 2, n = 20), and moderate/advanced (Hoehn and Yahr, 2.5-3, n = 20) stages of the disease. Using a cross-sectional study design, we compared their performance on a simple reaction-time task and a stop-signal task randomly performed twice on dopaminergic medication (ON) and after medication withdrawal (OFF). Normative data were collected on 30 healthy controls. Results suggest that medication effects are stage-dependent. In Hoehn and Yahr 1-1.5 patients, drugs selectively impair reactive inhibition, leaving proactive inhibition unaffected. In the ON state, Hoehn and Yahr two patients experienced impaired proactive inhibition, whereas reactive inhibition is no longer affected, as it deteriorates even during the OFF state. By contrast, Hoehn and Yahr 2.5-3 patients exhibited less efficient reactive and proactive inhibition in the OFF state, and medication slightly improved proactive inhibition. This evidence aligns with the dopamine overdose hypothesis, indicating that drug administration may overdose intact dopamine circuitry in the earliest stages, impairing associated cognitive functions. In later stages, the progressive degeneration of dopaminergic neurons prevents the overdose and can exert some beneficial effects. Thus, our findings suggest that inhibitory control assessment might help tailor pharmacological therapy across the disease stage to enhance Parkinson's disease patients' quality of life by minimizing the hampering of inhibitory control and maximizing the reduction of motor symptoms.

Transcranial focused ultrasound to human rIFG improves response inhibition through modulation of the P300 onset latency.

Response inhibition in humans is important to avoid undesirable behavioral action consequences. Neuroimaging and lesion studies point to a locus of inhibitory control in the right inferior frontal gyrus (rIFG). Electrophysiology studies have implicated a downstream event-related potential from rIFG, the fronto-central P300, as a putative neural marker of the success and timing of inhibition over behavioral responses. However, it remains to be established whether rIFG effectively drives inhibition and which aspect of P300 activity uniquely indexes inhibitory control-ERP timing or amplitude. Here, we dissect the connection between rIFG and P300 for inhibition by using transcranial-focused ultrasound (tFUS) to target rIFG of human subjects while they performed a Stop-Signal task. By applying tFUS simultaneously with different task events, we found behavioral inhibition was improved, but only when applied to rIFG simultaneously with a 'stop' signal. Improved inhibition through tFUS to rIFG was indexed by faster stopping times that aligned with significantly shorter N200/P300 onset latencies. In contrast, P300 amplitude was modulated during tFUS across all groups without a paired change in behavior. Using tFUS, we provide evidence for a causal connection between anatomy, behavior, and electrophysiology underlying response inhibition.

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

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

Assessing the Longitudinal Associations Between Decision-Making Processes and Attention Problems in Early Adolescence.

Cognitive functions and psychopathology develop in parallel in childhood and adolescence, but the temporal dynamics of their associations are poorly understood. The present study sought to elucidate the intertwined development of decision-making processes and attention problems using longitudinal data from late childhood (9-10 years) to mid-adolescence (11-13 years) from the Adolescent Brain Cognitive Development (ABCD) Study (n = 8918). We utilised hierarchical drift-diffusion modelling of behavioural data from the stop-signal task, parent-reported attention problems from the Child Behavior Checklist (CBCL), and multigroup univariate and bivariate latent change score models. The results showed faster drift rate was associated with lower levels of inattention at baseline, as well as a greater reduction of inattention over time. Moreover, baseline drift rate negatively predicted change in attention problems in females, and baseline attention problems negatively predicted change in drift rate. Neither response caution (decision threshold) nor encoding- and responding processes (non-decision time) were significantly associated with attention problems. There were no significant sex differences in the associations between decision-making processes and attention problems. The study supports previous findings of reduced evidence accumulation in attention problems and additionally shows that development of this aspect of decision-making plays a role in developmental changes in attention problems in youth.

Poorer inhibitory control was related to greater food intake across meals varying in portion size: A randomized crossover trial

Individuals eat more food when larger portions are served, and this portion size effect could be influenced by inhibitory control (the ability to suppress an automatic response). Inhibitory control may also relate to obesogenic meal behaviors such as eating faster, taking larger bites, and frequent switching between meal components (such as bites of food and sips of water). In a randomized crossover design, 44 adults ate lunch four times in the laboratory. Lunch consisted of a pasta dish that was varied in portion size (400, 500, 600, or 700 g) along with 700 g of water. Meals were video-recorded to assess meal duration and bite and sip counts, which were used to determine mean eating rate (g/min), mean bite size (g/bite), and number of switches between bites and sips. Participants completed a food-specific stop-signal task, which was used to calculate Stop-Signal Reaction Time (SSRT). Across participants, SSRT values ranged from 143 to 306 msec, where greater SSRT indicates poorer inhibitory control. As expected, serving larger portions increased meal intake (p < 0.0001); compared to the smallest portion, intake of the largest increased by 121 ± 17 g (mean ± SEM). SSRT did not moderate the portion size effect (p = 0.34), but individuals with poorer inhibitory control ate more across all meals: 24 ± 11 g for each one SD unit increase in SSRT (p = 0.035). SSRT was not related to eating rate or bite size (both p > 0.13), but poorer inhibitory control predicted greater switching between bites and sips, such that 1.5 ± 0.7 more switches were made during meals for each one SD unit increase in SSRT (p = 0.03). These findings indicate that inhibitory control can contribute to overconsumption across meals varying in portion size, potentially in part by promoting switching behavior.

A novel approach to modulating response inhibition: Multi-channel beta transcranial alternating current stimulation

BackgroundDeficits in response inhibition are associated with numerous psychiatric disorders. Previous studies have revealed the crucial role of the right inferior frontal gyrus (rIFG), pre-supplementary motor area (preSMA), and beta activity in these brain regions in response inhibition. Multi-channel transcranial alternating current stimulation (tACS) has garnered significant attention for its ability to modulate neural oscillations in brain networks. In this study, we employed multi-channel tACS targeting rIFG-preSMA network to investigate its impact on response inhibition in healthy adults. MethodsIn Experiment 1, 70 healthy participants were randomly assigned to receive 20 Hz in-phase, anti-phase, or sham stimulation over rIFG-preSMA network. Response inhibition was assessed using the stop-signal task during and after stimulation, and impulsiveness was measured via the Barratt Impulsiveness Scale. Additionally, 25 participants received stimulation at the left supraorbital area to account for potential effects of the "return" electrode. Experiment 2, consisting of 25 participants, was conducted to validate the primary findings of Experiment 1, including both in-phase and sham stimulation conditions, based on prior estimations derived from the results of Experiment 1. ResultsIn Experiment 1, we found that in-phase stimulation significantly improved response inhibition compared with sham stimulation, whereas anti-phase stimulation did not. These findings were consistently replicated in Experiment 2. We also conducted an exploratory analysis of the multi-channel tACS impact, revealing that its effects primarily emerged during the post-stimulation phase. Furthermore, individuals with higher baseline attentional impulsiveness showed greater improvements in the in-phase stimulation group. ConclusionsThese results demonstrate that in-phase beta-tACS over rIFG-preSMA network can effectively improve response inhibition in healthy adults and provides a new potential treatment for patients with deficits in response inhibition.

Stop affordance task: a measure of the motor interference effect.

The term affordance refers to the property or quality of an object that indicates the ways in which it could potentially be used. Affordances elicit automatic motor representations that sometimes differ from the current action representation, resulting in behavioural interference effects. This affordance-induces interference could result in automatic and involuntary behavioural inhibition, probably according to the same mechanism that controls the voluntary motor inhibition. Nevertheless, few studies have considered how voluntary response inhibition is modulated by affordance. In this study, we assess the effect of affordance on voluntary action inhibition using a stop-signal task with an affordance object as a Stop Signal. An image of a mug, with the handle orientated in the same or in the opposite direction of the hand recruited to respond at the target, was used as Stop Signal. Our results showed a reduction of the time necessary to withhold the response when the handle of the mug was pointed toward the hand pre-activated to respond. This effect indicates an increased inhibition due to the mismatch between the motor representation elicited by the affordance and the motor representation pre-activated by the target. This suggests a specific interference effect, reflected in an enhanced ability to inhibit an ongoing action.

You Got It in Your Hands: Stop-Signal Modality Influences on Reactive Response Inhibition with Gaming Controls

Mastering the art of stopping initiated actions is vital when playing video games. However, what characteristics make up the perfect warning or stop-signal remains unclear. In the present study we compared performance in a basic and a gamified stop-signal task depending on different stop-signal modalities: auditory, haptic and audio-haptic. Data from a complete within-subjects design (N = 24), revealed an advantage of haptic or audio-haptic stop-signals as compared to purely auditory ones. Further, results show an overall slower performance in the game-version compared to the basic version. With regards to the subjective experience, the results revealed higher motivation to perform in the gamified task, but a somewhat deeper flow experience in the basic task. In sum, these results confirm that stop-signal modality influences reactive response inhibition in both basic and gamified tasks. Future research may extend and generalize these findings to other cross-modal and more complicated gaming setups. Game developers may draw on these findings to optimize the communication of stop signals via vibrations in a handheld controller.

Investigating the relationship between inhibitory control and dietary adherence among patients with type 2 diabetes mellitus based on subjective and objective measures

BackgroundDietary management has been recommended as the cornerstone of type 2 diabetes mellitus (T2DM) management. However, low adherence to dietary recommendations has been identified in both developed and developing countries. Previous research suggests that inhibitory control influences eating behavior, but few studies have been conducted in patients with T2DM. Thus, we aimed to explore the relationship between inhibitory control and dietary adherence among patients with T2DM.MethodsA total of 393 patients with T2DM from the endocrinology departments of three tertiary hospitals in China were enrolled by the convenience sampling method. Dietary adherence was measured by the Dietary Behavior Adherence Scale for Patients with Type 2 Diabetes Mellitus. Additionally, inhibitory control was subjectively measured by the Behavior Rating Inventory of Executive Function-Adult version (BRIEF-A) and objectively assessed by the stop signal task (SST) and the Stroop task. The relationship between inhibitory control and dietary adherence was analyzed using Pearson correlation analysis and hierarchical regression analysis.ResultsSubjectively measured inhibitory control had a significant predictive effect for dietary adherence after controlling for demographic and clinical variables. Adding the inhibitory control variable to the regression equation resulted in the following values: overall model F (19, 373) = 7.096, p < 0.001, increase in R2 value by 0.069, change in F (1, 373) = 35.219, p < 0.001. Similarly, the performance of the Stroop task had a significant predictive effect for dietary adherence to some foods, i.e., carbohydrate and fat. Adding the Stroop effect variable to the regression equation resulted in the following values: overall model F (19, 81) = 2.848, p = 0.005, increase in R2 value by 0.060, change in F (1, 81) = 8.137, p = 0.006.ConclusionsInhibitory control was a predictor of dietary adherence in patients with T2DM. Future interventions should investigate whether inhibitory control training results in the improvement of dietary adherence in patients with T2DM.

Comparison of online and offline applications of dual-site transcranial alternating current stimulation (tACS) over the pre-supplementary motor area (preSMA) and right inferior frontal gyrus (rIFG) for improving response inhibition

The efficacy of transcranial alternating current stimulation (tACS) is thought to be brain state-dependent, such that tACS during task performance would be hypothesised to offer greater potential for improving performance compared to tACS at rest. However, to date, no empirical study has tested this postulation. The current study compared the effects of dual-site beta tACS applied during a stop signal task (online) to the effects of the same tACS protocol applied prior to the task (offline) and a sham control stimulation in 53 young, healthy adults (32 female; 18–35 yrs). The right inferior frontal gyrus (rIFG) and centre (midline) of the pre-supplementary motor area (preSMA), which are thought to play critical roles in action cancellation, were simultaneously stimulated, sending phase-synchronised stimulation for 15 min with the aim of increasing functional connectivity. The offline group showed significant within-group improvement in response inhibition without showing overt task-related changes in functional connectivity measured with EEG connectivity analysis, suggesting offline tACS is efficacious in inducing behavioural changes potentially via a post-stimulation early plasticity mechanism. In contrast, neither the online nor sham group showed significant improvements in response inhibition. However, EEG connectivity analysis revealed significantly increased task-related functional connectivity following online stimulation and a medium effect size observed in correlation analyses suggested that an increase in functional connectivity in the beta band at rest was potentially associated with an improvement in response inhibition. Overall, the results indicate that both online and offline dual-site beta tACS can be beneficial in improving inhibitory control via distinct underlying mechanisms.