No-go Trials Research Articles

Inhibitory dysfunction may cause prospective memory impairment in temporal lobe epilepsy (TLE) patients: an event-related potential study.

Prospective memory (PM) is the ability to remember future intentions, and PM function is closely related to independence in daily life, particularly in patients with temporal lobe epilepsy (TLE). As PM involves various cognitive components of attention, working memory, inhibition and other executive functions, this study investigated how TLE may affect PM components and the underlying neural mechanisms. Sixty-four subjects were recruited, including 20 refractory TLE patients, 18 well-controlled TLE patients and 26 age-matched healthy controls. A set of neuropsychological tests was administered to assess specific brain functions. An event-related potential (ERP) task was used to further explore how PM and its components would be differentially affected in the two TLE types. Our findings revealed that: (1) refractory TLE patients scored lower than the healthy controls in the digit span, Verbal Fluency Test and Symbol Digit Modalities Test; (2) refractory TLE patients exhibited impaired PM performance and reduced prospective positivity amplitudes over the frontal, central and parietal regions in ERP experiments when compared to the healthy controls; and (3) decreased P3 amplitudes in the nogo trials were observed over the frontal-central sites in refractory but not in well-controlled TLE patients. To our knowledge, this is the first ERP study on PM that has specifically identified PM impairment in refractory but not in well-controlled TLE patients. Our finding of double dissociation in PM components suggests that inhibition dysfunction may be the main reason for PM deficit in refractory TLE patients. The present results have clinical implications for neuropsychological rehabilitation in TLE patients.

Neurophysiological mechanisms underlying the differential effect of reward prospect on response selection and inhibition

Reward and cognitive control play crucial roles in shaping goal-directed behavior. Yet, the behavioral and neural underpinnings of interactive effects of both processes in driving our actions towards a particular goal have remained rather unclear. Given the importance of inhibitory control, we investigated the effect of reward prospect on the modulatory influence of automatic versus controlled processes during response inhibition. For this, a performance-contingent monetary reward for both correct response selection and response inhibition was added to a Simon NoGo task, which manipulates the relationship of automatic and controlled processes in Go and NoGo trials. A neurophysiological approach was used by combining EEG temporal signal decomposition and source localization methods. Compared to a non-rewarded control group, rewarded participants showed faster response execution, as well as overall lower response selection and inhibition accuracy (shifted speed-accuracy tradeoff). Interestingly, the reward group displayed a larger interference of the interactive effects of automatic versus controlled processes during response inhibition (i.e., a larger Simon NoGo effect), but not during response selection. The reward-specific behavioral effect was mirrored by the P3 amplitude, underlining the importance of stimulus–response association processes in explaining variability in response inhibition performance. The selective reward-induced neurophysiological modulation was associated with lower activation differences in relevant structures spanning the inferior frontal and parietal cortex, as well as higher activation differences in the somatosensory cortex. Taken together, this study highlights relevant neuroanatomical structures underlying selective reward effects on response inhibition and extends previous reports on the possible detrimental effect of reward-triggered performance trade-offs on cognitive control processes.

Neurodevelopmental vulnerability to psychosis: developmentally-based methods enable detection of early life inhibitory control deficits that predict psychotic-like experiences at the transition to adolescence.

Inhibitory control develops in early childhood, and atypical development may be a measurable marker of risk for the later development of psychosis. Additionally, inhibitory control may be a target for intervention. Behavioral performance on a developmentally appropriate Go/No-Go task including a frustration manipulation completed by children ages 3-5 years (early childhood; n = 107) was examined in relation to psychotic-like experiences (PLEs; 'tween'; ages 9-12), internalizing symptoms, and externalizing symptoms self-reported at long-term follow-up (pre-adolescence; ages 8-11). ERP N200 amplitude for a subset of these children (n = 34) with electrophysiological data during the task was examined as an index of inhibitory control. Children with lower accuracy on No-Go trials compared to Go trials in early childhood (F(1,101) = 3.976, p = 0.049), evidenced higher PLEs at the transition to adolescence 4-9 years later, reflecting a specific deficit in inhibitory control. No association was observed with internalizing or externalizing symptoms. Decreased accuracy during the frustration manipulation predicted higher internalizing, F(2,202) = 5.618, p = 0.004, and externalizing symptoms, F(2,202) = 4.663, p = 0.010. Smaller N200 amplitudes were observed on No-Go trials for those with higher PLEs, F(1,101) = 6.075, p = 0.020; no relationship was observed for internalizing or externalizing symptoms. Long-term follow-up demonstrates for the first time a specific deficit in inhibitory control behaviorally and electrophysiology, for individuals who later report more PLEs. Decreases in task performance under frustration induction indicated risk for internalizing and externalizing symptoms. These findings suggest that pathophysiological mechanisms for psychosis are relevant and discriminable in early childhood, and further, suggest an identifiable and potentially modifiable target for early intervention.

Personal relative deprivation impairs the ability to inhibit impulsive responses: an exploratory ERP study.

Evidence indicates that personal relative deprivation (PRD) can lead to various impulsive behaviors. Given that impulsive behaviors are usually caused by a failure to exert cognitive control, the purpose of this study was to explore whether PRD affects the ability to exert cognitive control on behavior. Forty-six healthy participants were randomly assigned to PRD or non-PRD group. Participants of the PRD group were told their income would lie below the Chinese average. While their electrophysiological responses were recorded, they underwent a Go/No-Go task simultaneously assessing the ability to detect response conflict and inhibit the predominant response. We found that the individuals with induced PRD show diminished ability to inhibit predominant response. We suggest this is because PRD-related concerns consume cognitive resources, leaving less for other tasks. However, we also found that individuals with induced PRD show enhanced ability to detect conflict. This might be because that individuals with induced PRD were sensitive to potentially threatening information (high-conflict No-Go trials) and they can detect conflict with less cognitive resources. These findings may facilitate future attempts to design interventions for relatively deprived individuals to manage their impulsive behavior.

Mind-wandering does not always rhyme with proactive functioning! Changes in the temporal dynamics of the mPFC-mediated theta oscillations during moments of mind-wandering

The reduced engagement of the cognitive control network has been documented widely during mind-wandering (MW). However, it remains unknown how MW affects the neural dynamics of cognitive control processes. From this perspective, we explored neural dynamics mediated by the medial prefrontal cortex (mPFC). Their engagement can be both transient (or reactive) and anticipated (or proactive). A total of fortyseven healthy subjects (37 females) were engaged in a long-lasting sustained-attention Go/NoGo task. Subjective probes were used to detect MW episodes. Channel-based EEG time-frequency analysis was performed to measure the theta oscillations, an index of the mPFC activity. The theta oscillations were computed immediately after conflictual NoGo trials to explore the reactive engagement of the mPFC. Proactive control was measured on the Go trials preceded the NoGo. Behaviorally, periods of MW were associated with an increase in errors and in RT variability in comparison to on-task periods. The analysis of the frontal midline theta power (MFθ) revealed that MW periods were associated with lower anticipated/proactive engagement and similar transient/reactive engagement of mPFC-mediated processes. Moreover, the communication between the mPFC and the DLPFC, as revealed by the poorer theta synchronization between these two regions, was also impaired during MW periods. Our results provide new insights about performance impairment during MW. They could be an important step in improving the existing understanding of the altered performances that are reported for some disorders that are known to be associated with excessive MW.

Deep learning on independent spatial EEG activity patterns delineates time windows relevant for response inhibition.

Inhibitory control processes are an important aspect of executive functions and goal-directed behavior. However, the mostly correlative nature of neurophysiological studies was not able to provide insights which aspects of neural dynamics can best predict whether an individual is confronted with a situation requiring the inhibition of a response. This is particularly the case when considering the complex spatio-temporal nature of neural processes captured by EEG data. In the current study, we ask whether independent spatial activity profiles in the EEG data are useful to predict whether an individual is confronted with a situation requiring response inhibition. We combine independent component analysis (ICA) with explainable artificial intelligence approaches (EEG-based deep learning) using data from a Go/Nogo task (N = 255 participants). We show that there are four dissociable spatial activity profiles important to classify Go and Nogo trials as revealed by deep learning. Of note, for all of these four independent activity profiles, neural activity in the time period between 300 and 550 ms after stimulus presentation was most informative. Source localization analyses further revealed regions in the pre-central gyrus (BA6), the middle frontal gyrus (BA10), the inferior frontal gyrus (BA46), and the insular cortex (BA13) were associated with the isolated spatial activity profiles. The data suggest concomitant processes being reflected in the identified time window. This has implications for the ongoing debate on the functional significance of event-related potential correlates of inhibitory control.

Electrophysiological Correlates of the Interaction of Physical and Numerical Size in Symbolic Number Processing: Insights from a Novel Go/Nogo Numerical Stroop Task.

The interaction of physical and numerical size has been investigated and repeatedly demonstrated in the numerical Stroop task, in which participants compare digits of different physical sizes. It is, however, not entirely clear yet what psychological processes contribute to this interaction. The aim of the present study is to investigate the role of inhibition in the interaction of physical and numerical size, by introducing a novel paradigm that is suitable to elicit inhibition-related event-related potential components. To this end, we combined the go/nogo paradigm with the numerical Stroop task while measuring EEG and reaction times. Participants were presented with Arabic number pairs and had to press a button if the number on one side was numerically larger and they had to refrain from responding if the number on the other side was numerically larger. The physical size of the number pairs was also manipulated, in order to create congruent, neutral, and incongruent trials. Behavioural results confirmed the well-established numerical distance and numerical Stroop effects. Analysis of electrophysiological data revealed the classical go/nogo electrophysiological effects with numerical stimuli, and showed that peak amplitudes were larger for nogo than for go trials on the N2, as well as on the P3 component, on frontal and midline electrodes. When analysing the congruency effects, the peak amplitude of N2 was larger in incongruent trials than in neutral and congruent trials, while there was no evidence of a congruency effect on the P3 component peaks. Further analysis of the electrophysiological data revealed an additional facilitatory effect in the go trials, as well as an additional interference effect in the nogo trials. Taken together, it seems that interference effects are probably resolved by inhibitory processes and that facilitatory effects are affected by different cognitive control processes required by go versus nogo trials.

Task difficulty modulates age-related differences in functional connectivity during word production

Older adults typically report increased difficulty with language production, while its neural bases are less clear. The current study investigated the neural bases of age-related differences in language production at the word level and the modulating effect of task difficulty, focusing on task-based functional connectivity. Using an English phonological Go/No-Go picture naming task, task difficulty was manipulated by varying the proportion of naming trials (Go trials) and inhibition trials (No-Go trials) across runs. Behaviorally, compared to younger adults, older adults performed worse, and showed larger effects of task difficulty. Neurally, older adults had lower within language network connectivity compared to younger adults. Moreover, older adults’ language network became less segregated as task difficulty increased. These results are consistent with the Compensation-Related Utilization of Neural Circuits Hypothesis, suggesting that the brain becomes less specified and efficient with increased task difficulty, and that these effects are stronger among older adults (i.e., more dedifferentiated).

Neural Correlates of the p Factor in Adolescence: Cognitive Control With and Without Enhanced Positive Affective Demands

BackgroundRecent research has aimed to characterize processes underlying general liability toward psychopathology, termed the p factor. Given previous research linking the p factor with difficulties in both executive functioning and affective regulation, the present study investigated nonaffective and positive affective inhibition in the context of a sustained attention/inhibition paradigm in adolescents exhibiting mild to severe psychopathology. MethodsFunctional magnetic resonance imaging data were collected during an integrated reward conditioning and go/no-go task in 138 adolescents assigned female at birth. We modeled the p factor using hierarchical confirmatory factor analysis. Positive affective inhibition was measured by examining responses to no-go stimuli with a history of reward conditioning. We examined associations between p factor scores and neural function and behavioral performance. ResultsConsistent with nonaffective executive function as a primary risk factor, p factor scores were associated with worse behavioral performance and hypoactivation in the left superior frontal gyrus and middle frontal gyrus during response initiation (go trials). The p factor scores were additionally associated with increased error-related signaling in the temporal cortex during incorrect no-go trials. ConclusionsDuring adolescence, a period characterized by heightened risk for emergent psychopathology, we observed unique associations between p factor scores and neural and behavioral indices of response initiation, which relies primarily on sustained attention. These findings suggest that shared variation in mental disorder categories is characterized in part by sustained attention deficits. While we did not find evidence that the p factor was associated with inhibition in this study, this observation is consistent with our hypothesis that the p factor would be related to nonaffective control processes.

Attention, response inhibition, impulsivity, and decision-making within luteal phase in women with premenstrual dysphoric disorder.

Cognitive impairment is a key feature of depressive disorder. Various forms of cognitive function have yet to be investigated in women with premenstrual dysphoric disorder (PMDD) during early luteal (EL) and late luteal (LL) phases. Therefore, we evaluated response inhibition and attention in PMDD in these two phases. We also examined the associations between cognitive functions, impulsivity, decision-making style, and irritability. There is a total of 63 female participants with PMDD and 53 controls, as determined through psychiatric diagnostic interviewing and a weekly symptoms checklist. The participants completed a Go/No-go task, Dickman's impulsivity inventory, Preference for Intuition and Deliberation scale, and the Buss-Durkee Hostility Inventory: Chinese Version-Short Form at the EL and LL phases. The women with PMDD had poorer attention in the Go trials at the LL phase and poorer response inhibition in the No-go trials at the EL and LL phases. Repeated measures analysis of variance revealed an LL exacerbation of deficit in attention among PMDD group. In addition, impulsivity negatively correlated with response inhibition at the LL phase. Preference for deliberation correlated with attention at the LL phase. Women with PMDD experienced LL declined attention and impaired response inhibition across the luteal phase. Response inhibition is linked to impulsivity. The deficit in attention links preference for deliberation among women with PMDD. These results reveal the different courses in different domains of cognitive impairment in PMDD. Further studies are required to elucidate the mechanism underlying cognitive dysfunction in PMDD.

Aperiodic neural activity reflects metacontrol.

Higher-level cognitive functions are mediated via complex oscillatory activity patterns and its analysis is dominating cognitive neuroscience research. However, besides oscillatory (period) activity, also aperiodic activity constitutes neural dynamics, but its relevance for higher-level cognitive functions is only beginning to be understood. The present study examined whether the broadband EEG aperiodic activity reflects principles of metacontrol. Metacontrol conceptualizes whether it is more useful to engage in more flexible processing of incoming information or to shield cognitive processes from incoming information (persistence-heavy processing). We examined EEG and behavioral data from a sample of n = 191 healthy participants performing a Simon Go/NoGo task that can be assumed to induce different metacontrol states (persistence-biased vs. flexibility-biased). Aperiodic activity was estimated using the FOOOF toolbox in the EEG power spectrum. There was a higher aperiodic exponent and offset in NoGo trials compared with Go trials, in incongruent (Go) trials compared with congruent (Go) trials. Thus, aperiodic activity increases during persistence-heavy processing, but decreases during flexibility-heavy processing. These findings link aperiodic features of the EEG signal and concepts describing the dynamics of how cognitive control modes are applied. Therefore, the study substantially extends the importance of aperiodic activity in understanding cognitive functions.

Error-related brain activity associated with obsessive-compulsive symptoms in youth.

Subclinical obsessive-compulsive symptoms (OCS) are common in children, and increase risk for later onset of obsessive-compulsive disorder (OCD). In pediatric patients with OCD, neuroimaging research implicates altered neural mechanisms for error-processing, but whether abnormal brain response occurs with subclinical OCS remains poorly understood. Using functional magnetic resonance imaging (fMRI), 113 youth (8-18 years; 45 female) from a community sample were scanned during an error-eliciting Go/No-Go task. OCS were assessed dimensionally using the obsessive-compulsive subscale of the Child Behavior Checklist. The association between OCS scores and error-related brain activity was examined at the whole-brain level. Lower OCS scores associated with stronger response to errors in dorsal anterior cingulate cortex (dACC), caudate, putamen, thalamus, and occipital cortex. Additionally, lower OCS related to higher capacity for inhibitory control, as indexed by greater accuracy on No-Go trials during fMRI scanning. The relationship between lower OCS and better accuracy on No-Go trials was mediated by greater error-related dACC activity. The inverse relationship between OCS and error-related activity in the dACC and extended cortical-striatal-thalamic circuitry may index an adaptive process by which subclinical OCS are minimized in youth. Further, these results identify an observable pattern of brain activity that tracks with subclinical OCS severity. Understanding the link between neural networks for error processing and the normal to abnormal range of OCS may pave the way for brain-based strategies to identify children who are more likely to develop OCD and enable the targeting of preventive strategies to reduce risk.

Measuring food-related inhibition with go/no-go tasks: Critical considerations for experimental design

The use of go/no-go tasks to assess inhibitory control over food stimuli is becoming increasingly popular. However, the wide variability in the design of these tasks makes it difficult to fully leverage their results. The goal of this commentary was to provide researchers with crucial aspects to consider when designing food-related go/no-go experiments. We examined 76 studies that used food-themed go/no-go tasks and extracted characteristics related to participant population, methodology, and analysis. Based on our observations of common issues that can influence study conclusions, we stress the importance for researchers to design an appropriate control condition and match stimuli between experimental conditions in terms of emotional and physical properties. We also emphasize that stimuli should be tailored to the participants under study, whether at the individual or group level. To ensure that the task truly measures inhibitory abilities, researchers should promote the establishment of a prepotent response pattern by presenting more go than no-go trials and by using short trials. Researchers should also pre-specify the criteria used to identify potentially invalid data. While go/no-go tasks represent valuable tools for studying food cognition, researchers should choose task parameters carefully and justify their methodological and analytical decisions in order to ensure the validity of results and promote best practices in food-related inhibition research.

Challenging inhibitory control with high- and low-calorie food: A behavioural and TMS study.

Most people are often tempted by their impulses to "indulge" in high-calorie food, even if this behaviour is not consistent with their goal to control weight in the long term and might not be healthy. The outcome of this conflict is strongly dependent on inhibitory control. It has already been reported that individuals with weaker inhibitory control consume more high-calorie food, are more often unsuccessful dieters, overweight or obese compared to people with more effective inhibitory control. In the present study, we aimed at investigating inhibitory control in the context of human eating behaviour. A sample of 20 healthy normal-weight adults performed a 50% probability visual affective Go/NoGo task involving food (high- and low-calorie) and non-food images as stimuli. Single-pulse transcranial magnetic stimulation (TMS) was administered over the right primary motor cortex (M1) either 300 ms after image presentation to measure corticospinal excitability during the different stimulus categories or 300 ms after the appearance of a fixation point, as a control stimulation condition. The experimental session consisted of a food target and a non-food target block. Behavioural outcomes showed a natural implicit inclination towards high-calorie food in that participants were faster and more accurate compared to the other categories. This advantage was selectively deleted by TMS, which slowed down reaction times. MEPs did not differ according to the stimulus category, but, as expected, were bigger for Go compared to NoGo trials. Participants judged high-calorie food also as more appetising than low-calorie food images. Overall, our results point to a differential modulation when targeting inhibitory control, in favour of the more palatable food category (high-calorie). Present data suggest that the activity of the motor system is modulated by food nutritional value, being more engaged by appetising food. Future work should explore to what extent these processes are affected in patients with eating disorders and should aim to better characterise the related dynamics of cortical connectivity within the motor network.

Factors related to the development of executive functions: A cumulative dopamine genetic score and environmental factors predict performance of kindergarten children in a go/nogo task

BackgroundThis study aimed at investigating the interaction between genetic and environmental factors in predicting executive function in children aged four to six years. MethodsResponse inhibition as index of EF was assessed in 197 children using a go/nogo task. A cumulative dopamine (DA) genetic score was calculated, indexing predisposition of low DA activity. Dimensions of parenting behavior and parental education were assessed. ResultsParental education was positively related to accuracy in nogo trials. An interaction between the cumulative genetic score and the parenting dimension Responsiveness predicted go RT indicating that children with a high cumulative genetic score and high parental responsiveness exhibited a careful response mode. ConclusionThe development of EF in kindergarten children is related to parental education as well as to an interaction between the molecular-genetics of the DA system and parenting behavior.

Automatic emotion regulation prompts response inhibition to angry faces in sub-clinical depression: An ERP study

The neurocognitive mechanism by which automatic emotion regulation (AER) affects emotion processing remains understudied in the context of psychopathology, such as depression. Participants with sub-clinical depression and healthy controls were randomly assigned to an emotion regulation priming group or a neutral priming group. All participants completed an emotional Go/No-go task by judging the gender of angry or happy faces. During the Go/No-go task, each trial was preceded by subliminal presentation of words describing emotion regulation goals or neutral goals as a manipulation of priming. The behavioral results showed that compared with neutral priming, subliminal priming of regulation goals increased the accuracy in No-go trials with angry faces only for sub-clinically depressed participants. In the ERP results, the main effect of regulation priming was significant in sub-clinically depressed participants, such that showing subliminal priming of regulation goals decreased the amplitude of N2 compared to the neutral priming. Similarly, for the sub-clinically depressed participants, regulation goal priming evoked smaller P3 in response to angry faces than to happy faces. No such pattern was found in neutral goal priming condition or for healthy controls. According to the automotive model of emotion regulation, once goals or norms related to emotion regulations are formed in the mind, a related regulation response could be activated without awareness. Our results suggest that subliminal priming of regulation goals could change the response inhibition to angry faces in sub-clinically depressed participants.

Cortical Patterns Shift from Sequence Feature Separation during Planning to Integration during Motor Execution.

Performing sequences of movements from memory and adapting them to changing task demands is a hallmark of skilled human behavior, from handwriting to playing a musical instrument. Prior studies showed a fine-grained tuning of cortical primary motor, premotor, and parietal regions to motor sequences: from the low-level specification of individual movements to high-level sequence features, such as sequence order and timing. However, it is not known how tuning in these regions unfolds dynamically across planning and execution. To address this, we trained 24 healthy right-handed human participants (14 females, 10 males) to produce four five-element finger press sequences with a particular finger order and timing structure in a delayed sequence production paradigm entirely from memory. Local cortical fMRI patterns during preparation and production phases were extracted from separate No-Go and Go trials, respectively, to tease out activity related to these perimovement phases. During sequence planning, premotor and parietal areas increased tuning to movement order or timing, regardless of their combinations. In contrast, patterns reflecting the unique integration of sequence features emerged in these regions during execution only, alongside timing-specific tuning in the ventral premotor, supplementary motor, and superior parietal areas. This was in line with the participants' behavioral transfer of trained timing, but not of order to new sequence feature combinations. Our findings suggest a general informational state shift from high-level feature separation to low-level feature integration within cortical regions for movement execution. Recompiling sequence features trial-by-trial during planning may enable flexible last-minute adjustment before movement initiation.SIGNIFICANCE STATEMENT Musicians and athletes can modify the timing and order of movements in a sequence trial-by-trial, allowing for a vast repertoire of flexible behaviors. How does the brain put together these high-level sequence features into an integrated whole? We found that, trial-by-trial, the control of sequence features undergoes a state shift from separation during planning to integration during execution across a network of motor-related cortical areas. These findings have implications for understanding the hierarchical control of skilled movement sequences, as well as how information in brain areas unfolds across planning and execution.

Cardiac timing and threatening stimuli influence response inhibition and ex-Gaussian parameters of reaction time in a Go/No-go task.

Sensorimotor responses vary as a function of the cardiac cycle phase. These effects, known as cardiac cycle time effects, have been explained by the inhibition of cardiac afferent signals on information processing. However, the validity of cardiac cycle time effects is challenged by mixed findings. Factors such as current information processing and affective context may modulate cardiac cycle time effects and account for inconsistencies in the literature. The current study examines the influence of cardiac cycle time and threatening stimuli on two aspects of sensorimotor processing, response speed and inhibition. Thirty-four participants (Mage =19.35 years; 29 female) completed an auditory Go/No-go task in no face, neutral face, and fearful face conditions. Faces were presented at either cardiac diastole or systole. Participants' reaction times (RTs) during Go trials and failures in response inhibition during No-go trials were recorded. The ex-Gaussian model was fit to RT data in each condition deriving the parameters, mu (μ) and tau (τ), that indicate response speed and attentional lapses, respectively. Repeated measures ANOVA were used to analyze behavioral data. Results showed that cardiac systole prolonged μ but decreased τ, and that cardiac diastole reduced inhibition errors in the fearful face condition but not in other conditions. These findings indicate that cardiac timing differentially modulates sensory-perceptual and top-down attentional processes and cardiac timing interacts with threatening contexts to influence response inhibition. These results highlight the specificity of cardiac cycle time effects on sensorimotor processing.

Children's screentime is associated with reduced brain activation during an inhibitory control task: A pilot EEG study

Children's screentime has been linked with a variety of behavioral consequences, including decreased inhibitory control. While children's screentime is associated with distinct functional brain differences, the links between screentime and neural markers of inhibitory control are unknown. Therefore, we examined these relationships in a pilot study using a Go/No-Go task (N = 20). After controlling for age, increased child screentime was significantly correlated with reduced P2 and P3 amplitudes elicited by No-Go trials. No significant relationships were observed with behavioral accuracy or response time. These findings indicate that children with greater screentime exhibit less robust neural processes for inhibitory control. Limitations and future directions are discussed within these preliminary findings.

Investigating task preparation and task performance as triggers of the backward inhibition effect

Backward inhibition is posited to aid task switching by counteracting the tendency to repeat a recent task. Evidence that factors such as cue transparency affect backward inhibition seems to imply that it is generated during task preparation, making its absence following trials on which a prepared task was not performed (nogo trials) surprising. However, the nogo method used in previous studies might have prevented detection of preparation-driven effects. We used a truncated-trial method instead, omitting stages of a trial with no need for a nogo signal. In Experiment 1, an n − 2 repetition cost (suggested to indicate backward inhibition) followed trials truncated after response selection, indicating that response execution is not necessary to trigger backward inhibition. In Experiments 2 and 3, no n − 2 repetition cost was obtained following trials truncated after cue presentation. To ensure some task preparation on cue-only trials, Experiment 4 used a double-registration procedure where participants responded to the task cue and the target on each trial. In contrast to Experiments 2 and 3, a small n − 2 repetition cost followed trials truncated after cue responses, affecting cue responses on the current trial. In addition, the n − 2 repetition cost was increased at cue responses and became evident at target responses when the preceding trial also involved a target response. These results imply that backward inhibition might be generated by processes occurring up to and including a cue response, affecting subsequent cue responses, as well as during task performance itself, affecting subsequent cue and target responses.