Event-related Potential Indices Research Articles

Alterations in working memory maintenance of fearful face distractors in depressed participants: An ERP study.

Task-irrelevant threatening faces (e.g., fearful) are difficult to filter from visual working memory (VWM), but the difficulty in filtering non-threatening negative faces (e.g., sad) is not known. Depressive symptoms could also potentially affect the ability to filter different emotional faces. We tested the filtering of task-irrelevant sad and fearful faces by depressed and control participants performing a color-change detection task. The VWM storage of distractors was indicated by contralateral delay activity, a specific event-related potential index for the number of objects stored in VWM during the maintenance phase. The control group did not store sad face distractors, but they automatically stored fearful face distractors, suggesting that threatening faces are specifically difficult to filter from VWM in non-depressed individuals. By contrast, depressed participants showed no additional consumption of VWM resources for either the distractor condition or the non-distractor condition, possibly suggesting that neither fearful nor sad face distractors were maintained in VWM. Our control group results confirm previous findings of a threat-related filtering difficulty in the normal population while also suggesting that task-irrelevant non-threatening negative faces do not automatically load into VWM. The novel finding of the lack of negative distractors within VWM storage in participants with depressive symptoms may reflect a decreased overall responsiveness to negative facial stimuli. Future studies should investigate the mechanisms underlying distractor filtering in depressed populations.

Examining the impact of schizotypal personality traits on event-related potential (ERP) indexes of sensory gating in a healthy population.

The aim of this study was to better understand the relation of schizotypy traits with sensory gating ability in a sample of community-dwelling individuals with high and low schizotypy traits. Sensory gating was assessed through the paired click paradigm and mid-latency evoked responses (i.e., P50, N100, P200), while schizotypy traits were assessed through the SPQ-BR which was used to classify participants into "high" and "low" schizotypy groups. Based on prior work, we hypothesized that those with the highest schizotypy scores would have reduced sensory gating ability. While this study does not show differences between relatively low and high schizotypy groups on sensory gating ability, it does suggest that our participants may have been experiencing deficits in attention allocation, a downstream cognitive processing measure. Scores on the SPQ-BR suggest that our sample was not close to the high end of the schizotypy traits which may help explain why no differences were found. This research shows the importance of including all levels of schizotypy ratings in clinical research as we can gain a clearer view of the impact of schizotypy on the brain and cognitive functioning in those with "high" levels of schizotypy. Additionally, this work highlights the importance of including measures of important factors such as impulsivity and sensation-seeking to better understand what aspects of schizotypy may be driving these sensory gating alterations reported in the literature.

Attentional enhancement predicts individual differences in visual working memory under go/no-go search conditions.

Attention-control processes transfer relevant information to visual working memory (WM) and prevent irrelevant information from consuming WM resources. Although event-related potentials (ERPs) have revealed attention-control processes associated with enhancement of relevant stimuli (targets) and suppression of irrelevant stimuli (distractors), only the suppressive processes have been found to predict WM capacity. We hypothesised a link between target-enhancement processes and WM capacity would be revealed in a task that requires more control than the conventional visual search paradigms used to study target selection. Here, participants searched for a pop-out target on Go trials and withheld responses on an equal number of randomly intermixed No-Go trials, depending on the colour of the stimulus array. Magnitudes of ERP indices associated with target enhancement (the singleton detection positivity, SDP, and N2pc) were positively correlated with individual differences in WM capacity. These relationships vanished when participants searched for the pop-out target on every trial, regardless of stimulus-array colour. Inhibitory processes associated with suppressing distractors (PD) and withholding responses (no-go P3) on No-Go trials did not predict WM capacity. These findings indicate that target-enhancement mechanisms control access to WM in search tasks that require dynamic control and disconfirm the view that the gateway to WM is entirely inhibitory by nature.

Impact of Impulsivity and Therapy Response in Eating Disorders from a Neurophysiological, Personality and Cognitive Perspective

Impulsivity, as a multidimensional construct, has been linked to eating disorders (EDs) and may negatively impact treatment response. The study aimed to identify the dimensions of impulsivity predicting poor remission of ED symptoms. A total of 37 ED patients underwent a baseline assessment of impulsive personality traits and inhibitory control, including the Stroop task and the emotional go/no-go task with event-related potentials (ERPs) analysis. The remission of EDs symptomatology was evaluated after 3 months of cognitive-behavioral therapy (CBT) and at a 2-year follow-up. Poor remission after CBT was predicted by poor inhibitory control, as measured by the Stroop task. At 2 years, the risk of poor remission was higher in patients with higher novelty seeking, lower inhibitory control in the Stroop and in ERPs indices (N2 amplitudes) during the emotional go/no-go task. The present results highlight inhibitory control negatively impacting both short- and long-term symptomatology remission in ED patients. On the other hand, high novelty seeking and ERPs indices of poor inhibition seem to be more specifically related to long-term remission. Therefore, a comprehensive assessment of the impulsivity dimension in patients with ED is recommended to tailor treatments and improve their efficacy.

Menstrual cycle and exogenous attention toward emotional expressions

Several studies suggest that the menstrual cycle affects emotional processing. However, these results may be biased by including women with premenstrual syndrome (PMS) in the samples. PMS is characterized by negative emotional symptomatology, such as depression and/or anxiety, during the luteal phase. This study aimed to explore the modulation of exogenous attention to emotional facial expressions as a function of the menstrual cycle in women without PMS. For this purpose, 55 women were selected (from an original volunteer sample of 790) according to rigorous exclusion criteria. Happy, angry, and neutral faces were presented as distractors, while both behavioral performance in a perceptual task and event-related potentials (ERPs) were recorded. This task was applied during both phases of the menstrual cycle (luteal and follicular, counterbalanced), and premenstrual symptomatology was monitored daily. Traditional and Bayesian ANOVAs on behavioral data (reaction times and errors in the task) and ERP indices (P1, N170, N2, and LPP amplitudes) confirmed the expected lack of an interaction of phase and emotion. Taken together, these results indicate that women free of PMS present steady exogenous attention levels to emotionally positive and negative stimuli regardless of the menstrual phase.

Familiarity is familiarity is familiarity: Event-related brain potentials reveal qualitatively similar representations of personally familiar and famous faces.

Humans excel in familiar face recognition, but often find it hard to make identity judgements of unfamiliar faces. Understanding of the factors underlying the substantial benefits of familiarity is at present limited, but the effect is sometimes qualified by the way in which a face is known-for example, personal acquaintance sometimes gives rise to stronger familiarity effects than exposure through the media. Given the different quality of personal versus media knowledge, for example in one's emotional response or level of interaction, some have suggested qualitative differences between representations of people known personally or from media exposure. Alternatively, observed differences could reflect quantitative differences in the level of familiarity. We present 4 experiments investigating potential contributory influences to face familiarity effects in which observers view pictures showing their friends, favorite celebrities, celebrities they dislike, celebrities about whom they have expressed no opinion, and their own face. Using event-related potential indices with high temporal resolution and multiple highly varied everyday ambient images as a strong test of face recognition, we focus on the N250 and the later Sustained Familiarity Effect (SFE). All known faces show qualitatively similar responses relative to unfamiliar faces. Regardless of personal- or media-based familiarity, N250 reflects robust visual representations, successively refined over increasing exposure, while SFE appears to reflect the amount of identity-specific semantic information known about a person. These modulations of visual and semantic representations are consistent with face recognition models which emphasize the degree of familiarity but do not distinguish between different types of familiarity. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Influence of reputational concern and social distance on moral decision-making under the harmful dilemma: Evidence from behavioral and ERPs study

<p id="p00005">Reputational concern has been suggested as an important determinant of human cooperative behavior and moral judgment in social interactions. Previous studies have demonstrated that reputational concern influences behavioral and neural responses during prosocial behaviors and decision-making, such as moral decision-making. Moral decision- making is a typical social decision-making process involving trade-offs between the self and others. It refers to the process in which individuals make optimal choices under the guidance of social systems and norms according to their own value orientations when faced with a variety of possible dilemmas and conflicts in behavioral choices. Emerging studies have shown that social distance modulates behavioral and neural responses during moral decision-making. However, little is known about how reputational concern and social distance interact to affect moral decision-making, particularly regarding the underlying cognitive neural mechanism of moral decision-making associated with proscriptive morality (i.e., harmful behavior). <break/>In the present study, we adopted the “shock-benefit dilemma” task and event-related potential (ERP) technology to examine temporal processing of the interactive influence of reputational concern and social distance on moral decision-making when faced with harmful dilemmas. Participants were instructed to complete a series of alternative dilemmas in an anonymous or public context. After being instructed whether their decisions were going to be made public to the target person, participants decided whether to deliver a certain intensity of painful electric shocks toward the targets (i.e., friends, acquaintances, or strangers) to receive money. A choice not to shock the targets meant that they would forego the benefit. Behavioral and neural responses were recorded while the participants made their decisions. The experiment consisted of 360 trials, including two blocks of anonymous and public situations and 120 trials with friends, acquaintances, and strangers. <break/>The results showed that participants administered fewer electric shocks to friends than to acquaintances and strangers, which suggested an obvious “egoistic altruism” decision tendency in anonymous situations. Participants spent more time and experienced greater disgust in dilemmas involving acquaintances relative to those involving friends and strangers, which showed an obvious “acquaintance effect”. However, these differences were weakened in public situations. As for the ERP results, the dilemmas involving acquaintances elicited a larger P260 component, which is associated with emotional responses, and late positive potential (LPP, 300~450 ms), which is associated with cognitive reasoning. However, these differences in ERP indices disappeared in public situations. <break/>The aim of this study was to explore the interaction between reputational concern and social distance in behavioral and neural responses during moral decision-making involving harmful dilemmas. The results supported the hypothesis that individuals follow the egoistic altruism moral principle to conduct moral decision-making involving reputational concern and social distance. These findings suggest that the uncertainty of acquaintance relations induces stronger negative emotions and cognitive load during moral decision-making, and reputational concern effectively weakens the aversion and dilemma conflict brought about by self-interest tendencies and interpersonal uncertainties.

Altered performance monitoring in Tourette Syndrome: an MEG investigation

The error-related negativity (ERN) is an event-related potential component indexing processes of performance monitoring during simple stimulus-response tasks: the ERN is typically enhanced for error processing and conflicting response representations. Investigations in healthy participants and different patient groups have linked the ERN to the dopamine system and to prefrontal information processing. As in patients with Tourette Syndrome (TS) both dopamine release and prefrontal information processing are impaired, we hypothesized that performance monitoring would be altered, which was investigated with magnetencephalography (MEG). We examined performance monitoring in TS patients by assessing the magnetic equivalent of the ERN (mERN). The mERN was investigated in tic-free trials of eight adult, unmedicated TS patients without clinically significant comorbidity and ten matched healthy controls while performing a Go/NoGo task in selected frontocentral channels. The analysis of the response-related amplitudes of the event-related magnetic field showed that TS patients, in contrast to controls, did not show earlier amplitude modulation (between 70 and 105 ms after response onset) depending on response type (errors or correct responses). In both groups significant mERN amplitudes in the time-window between 105 and 160 ms after response onset were detected thus pointing at only later error processing in TS patients. In TS patients, early error-related processing might be affected by an enhanced motor control triggered by a conflict between the targeted high task performance and tic suppression. TS patients seem to tend to initially process all responses as erroneous responses.

Emotional Prosodies Processing and Its Relationship With Neurodevelopment Outcome at 24 Months in Infants of Diabetic Mothers.

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy. Hyperglycemia of pregnancy is a risk not only for later obesity of the offspring but also do harm to their neurodevelopment from fetus. An ERP research has shown that children with autism spectrum disorder (ASD) was characterized by impaired semantic processing. In this study, we used event-related potential (ERP) to assess the procession of different emotional prosodies (happy, fearful, and angry) in neonates of diabetic mothers, compared to the healthy term infants. And to explore whether the ERP measure has potential value for the evaluation of neurodevelopmental outcome in later childhood. A total of 43 full-term neonates were recruited from the neonatology department of Peking University First Hospital from December 1, 2017 to April 30, 2019. They were assigned to infants of diabetic mothers (IDM) group (n = 23) or control group (n = 20) according to their mother's oral glucose tolerance test's (OGTT) result during pregnancy. Using an oddball paradigm, ERP data were recorded while subjects listened to deviation stimulus (20%, happy/fearful/angry prosodies) and standard stimulus (80%, neutral prosody) to evaluate the potential prognostic value of ERP indexes for neurodevelopment at 24 months of age. Results showed that 1) mismatch response (MMR) amplitudes in IDM group were lower than the control; 2) lower MMR amplitude to fearful prosody at frontal lobe was a high risk for increased Modified Checklist for Autism in Toddlers (M-CHAT) scores at 24 months. These findings suggests that hyperglycemia of pregnancy may influence the ability to process emotional prosodies in neonatal brain; it could be reflected by decreased MMR amplitude in response to fearful prosody. Moreover, the decreased MMR amplitude at the frontal lobe may indicated an increased risk of ASD.

Neural Bases of Age-Related Sensorimotor Slowing in the Upper and Lower Limbs.

With advanced age, there is a loss of reaction speed that may contribute to an increased risk of tripping and falling. Avoiding falls and injuries requires awareness of the threat, followed by selection and execution of the appropriate motor response. Using event-related potentials (ERPs) and a simple visual reaction task (RT), the goal of our study was to distinguish sensory and motor processing in the upper- and lower-limbs while attempting to uncover the main cause of age-related behavioral slowing. Strength (amplitudes) as well as timing and speed (latencies) of various stages of stimulus- and motor-related processing were analyzed in 48 healthy individuals (young adults, n = 24, mean age = 34 years; older adults, n = 24, mean age = 67 years). The behavioral results showed a significant age-related slowing, where the younger compared to older adults exhibited shorter RTs for the upper- (222 vs. 255 ms; p = 0.006, respectively) and the lower limb (257 vs. 274 ms; p = 0.048, respectively) as well as lower variability in both modalities (p = 0.001). Using ERP indices, age-related slowing of visual stimulus processing was characterized by overall larger amplitudes with delayed latencies of endogenous potentials in older compared with younger adults. While no differences were found in the P1 component, the later components of recorded potentials for visual stimuli processing were most affected by age. This was characterized by increased N1 and P2 amplitudes and delayed P2 latencies in both upper and lower extremities. The analysis of motor-related cortical potentials (MRCPs) revealed stronger MRCP amplitude for upper- and a non-significant trend for lower limbs in older adults. The MRCP amplitude was smaller and peaked closer to the actual motor response for the upper- than for the lower limb in both age groups. There were longer MRCP onset latencies for lower- compared to upper-limb in younger adults, and a non-significant trend was seen in older adults. Multiple regression analyses showed that the onset of the MRCP peak consistently predicted reaction time across both age groups and limbs tested. However, MRCP rise time and P2 latency were also significant predictors of simple reaction time, but only in older adults and only for the upper limbs. Our study suggests that motor cortical processes contribute most strongly to the slowing of simple reaction time in advanced age. However, late-stage cortical processing related to sensory stimuli also appears to play a role in upper limb responses in the elderly. This process most likely reflects less efficient recruitment of neuronal resources required for the upper and lower extremity response task in older adults.

Neural mechanisms of motor dysfunction in individuals at clinical high-risk for psychosis: Evidence for impairments in motor activation.

Motor abnormalities are a core feature of psychotic disorders observed from the premorbid period through chronic illness, suggesting motor dysfunction may reflect the pathophysiology of psychosis. Electrophysiology research in schizophrenia suggests impaired motor activation and preparation may underlie these motor abnormalities. Despite behavioral studies suggesting similar motor dysfunction in those at clinical high-risk (CHR) for psychosis, there have been no studies examining neural mechanisms of motor dysfunction in the CHR period, where research can inform pathophysiological and risk models. The present study used the lateralized readiness potential (LRP), an event-related potential index of motor activation and preparation, to examine mechanisms of motor dysfunction in 42 CHR and 41 control participants (N = 83, 56% female). Response competition was manipulated to determine whether deficits are secondary to cognitive control impairments or reflect primary motor deficits. Behaviorally, CHR participants exhibited overall slower responses than controls. Further, relative to controls, CHR participants showed reduced activation of correct but not incorrect responses, reflected in blunted LRP amplitude under weak response competition and no difference in amplitude associated with the incorrect response under strong response competition. This pattern of results suggests individuals at CHR for psychosis exhibit primary motor deficits in activating and preparing behavioral responses and are contrary to a deficit in cognitive control. Further, blunted LRP amplitude was associated with worsening of negative symptoms at 12-month follow-up. Together, these findings are consistent with LRP studies in psychosis and implicate motor activation deficits as potential mechanisms of motor dysfunction in the high-risk period. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Using event-related potentials to characterize inhibitory control and self-monitoring across impulsive and compulsive phenotypes: a dimensional approach to OCD.

"Subsyndromal" obsessive-compulsive disorder symptoms (OCDSs) are common and cause impaired psychosocial functioning. OCDSs are better captured by dimensional models of psychopathology, as opposed to categorical diagnoses. However, such dimensional approaches require a deep understanding of the underlying neurocognitive drivers and impulsive and compulsive traits (ie, neurocognitive phenotypes) across symptoms. This study investigated inhibitory control and self-monitoring across impulsivity, compulsivity, and their interaction in individuals (n = 40) experiencing mild-moderate OCDSs. EEG recording concurrent with the stop-signal task was used to elicit event-related potentials (ERPs) indexing inhibitory control (ie, N2 and P3) and self-monitoring (ie, error-related negativity and correct-related negativity (CRN): negativity following erroneous or correct responses, respectively). During unsuccessful stopping, individuals high in both impulsivity and compulsivity displayed enhanced N2 amplitude, indicative of conflict between the urge to respond and need to stop (F(3, 33) = 1.48, P < .05, 95% Cl [-0.01, 0.001]). Individuals high in compulsivity and low in impulsivity showed reduced P3 amplitude, consistent with impairments in monitoring failed inhibitory control (F(3, 24) = 2.033, P < .05, 95% CI [-0.002, 0.045]). Following successful stopping, high compulsivity (independent of impulsivity) was associated with lower CRN amplitude, reflecting hypo-monitoring of correct responses (F(4, 32) = 4.76, P < .05, 95% CI [0.01, 0.02]), and with greater OCDS severity (F(3, 36) = 3.32, P < .05, 95% CI [0.03, 0.19]). The current findings provide evidence for differential, ERP-indexed inhibitory control and self-monitoring profiles across impulsive and compulsive phenotypes in OCDSs.

Effects of modafinil on electroencephalographic microstates in healthy adults.

Modafinil has been proposed as a potentially effective clinical treatment for neuropsychiatric disorders characterized by cognitive control deficits. However, the precise effects of modafinil, particularly on brain network functions, are not completely understood. To address this gap, we examined the effects of modafinil on resting-state brain activity in 30 healthy adults using microstate analysis. Electroencephalographic (EEG) microstates are discrete voltage topographies generated from resting-state network activity. Using a placebo-controlled, within-subjects design, we examined changes to microstate parameters following placebo (0mg), low (100mg), and high (200mg) modafinil doses. We also examined the functional significance of these microstates via associations between microstate parameters and event-related potential indexes of conflict monitoring and automatic error processing (N2 and error-related negativity) and behavioral responses (accuracy and RT) from a subsequent flanker interference task. Five microstates emerged following each treatment condition, including four canonical microstates (A-D). Modafinil increased microstate C proportion and occurrence regardless of dose, relative to placebo. Modafinil also decreased microstate A proportion and microstate B proportion and occurrence relative to placebo. These modafinil-related changes in microstate parameters were not associated with similar changes in flanker ERPs or behavior. Finally, modafinil made transitions between microstates A and B less likely and transitions from A and B to C more likely. Previous fMRI work has correlated microstates A and B with auditory and visual networks and microstate C with a salience network. Thus, our results suggest modafinil may deactivate large-scale sensory networks in favor of a higher order functional network during resting-state in healthy adults.

The acute dose and baseline amplitude-dependent effects of CDP-choline on deviance detection (MMN) in chronic schizophrenia: A pilot study.

The detection of deviant auditory features is empirically supported as impaired in schizophrenia and has been shown to associate with functional outcome. Modulated by glutamate neurotransmission, this sensory process has also been shown to relate to the α7 nicotinic acetylcholine receptor (nAChR) system, a prioritized molecular target for the development of novel cognition targeted pharmacological treatments. This pilot study assessed the acute effects of CDP-Choline, a choline supplement with α7 nAChR agonist properties, on the mismatch negativity (MMN), an event-related potential index of the detection of an acoustic change, in a sample of individuals diagnosed with chronic schizophrenia. Utilizing a randomized, placebo-controlled, double-blind design, the dose-dependent (500 mg, 1,000 mg, 2,000 mg), baseline amplitude-dependent (low vs. high), and deviant feature-dependent effects of CDP-Choline on the MMN were examined. CDP-choline's effects interacted with dosage, deviance feature, and baseline amplitude with low baseline amplitude patients demonstrating enhanced MMNs, and high baseline amplitude patients demonstrating suppressed MMNs in response to CDP-Choline. These findings offer tentative support for the involvement of the α7 nAChR system in auditory MMN abnormalities in schizophrenia and supports further research assessing the effects of long-term treatment with CDP-Choline in the personalized treatment of auditory deviance processing impairments. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Temporal and Spectral Properties of the Auditory Mismatch Negativity and P3a Responses in Schizophrenia.

The mismatch negativity (MMN) event-related potential (ERP) indexes relatively automatic detection of changes in sensory stimuli and is typically attenuated in individuals with schizophrenia. However, contributions of different frequencies of electroencephalographic (EEG) activity to the MMN and the later P3a attentional orienting response in schizophrenia are poorly understood and were the focus of the present study. Participants with a schizophrenia-spectrum disorder (n = 85) and non-psychiatric control participants (n = 74) completed a passive auditory oddball task containing 10% 50 ms "deviant" tones and 90% 100 ms "standard" tones. EEG data were analyzed using spatial principal component analysis (PCA) applied to wavelet-based time-frequency analysis and MMN and P3a ERPs. The schizophrenia group compared to the control group had smaller MMN amplitudes and lower deviant-minus-standard theta but not alpha event-related spectral perturbation (ERSP) after accounting for participant age and sex. Larger MMN and P3a amplitudes but not latencies were correlated with greater theta and alpha time-frequency activity. Multiple linear regression analyses revealed that control participants showed robust relationships between larger MMN amplitudes and greater deviant-minus-standard theta inter-trial coherence (ITC) and between larger P3a amplitudes and greater deviant-minus-standard theta ERSP, whereas these dynamic neural processes were less tightly coupled in participants with a schizophrenia-spectrum disorder. Study results help clarify frequency-based contributions of time-domain (ie, ERP) responses and indicate a potential disturbance in the neural dynamics of detecting change in sensory stimuli in schizophrenia. Overall, findings add to the growing body of evidence that psychotic illness is associated with widespread neural dysfunction in the theta frequency band.

The Effects of Circadian Rhythm in Adolescents on Optimal Performance in Cognitive Tasks

Introduction: The circadian rhythm is a sleep-wake cycle determined by differences in serum melatonin and cortisol levels, and affects cognition and behaviour. Past research suggests that young adults tend to perform better on cognitive tasks during the afternoon and evening, which may be the optimal time of day in this population. This research protocol seeks to determine whether cognitive performance is affected at times assumed to be optimal for both populations (evening) compared with suboptimal times (morning). Methods: Individuals would be recruited and divided into two groups: adolescents 13–17 and younger adults aged ages 18–25, with all participants of the afternoon/evening chronotype. Saliva is collected directly preceding test-taking. Each group completes a standard computerized test of simple math, logical reasoning, and executive function at both their optimal time of day (TOD) (3:00 to 6:00 PM) and at their non-optimal time of day (8:00 to 11:00 AM). Neuroelectric activity is recorded using electroencephalography (EEG). Results: We hypothesize that adolescents and younger adults will be at their optimal performance level (measured by EEG and behavioural measures) between 3 to 6 P.M. rather than from 8 to 11 AM, due to their circadian rhythm. We expect TOD to influence reaction times and accuracy during task completion. A difference will be seen across many neural indices such as event-related potentials (ERPs) and alpha and theta power demonstrating optimal performance in the evening. Discussion: Higher cortisol levels and changes in amplitude and latency of P3, N2Pc, N450, and PD ERP indices and differences in alpha and theta frequencies may be associated with optimal cognitive performance. This is related to faster response time, focus, and overall higher accuracy. Based on the anticipated results, one could alter the timing of task completion to fit different age groups’ peak mental ability. Conclusion: Continuously working at non-optimal times could lead to chronic circadian rhythm disruption, which could result in the deterioration of physical and mental health. Aspects of everyday life, such as student test-taking times, can be improved to benefit both individuals and institutions by catering to an individual’s optimal TOD.

Cognitive effort exertion enhances electrophysiological responses to rewarding outcomes.

Recent work has highlighted neural mechanisms underlying cognitive effort-related discounting of anticipated rewards. However, findings on whether effort exertion alters the subjective value of obtained rewards are inconsistent. Here, we provide a more nuanced account of how cognitive effort affects subsequent reward processing in a novel task designed to assess effort-induced modulations of the Reward Positivity, an event-related potential indexing reward-related neural activity. We found that neural responses to both gains and losses were significantly elevated in trials requiring more versus less cognitive effort. Moreover, time-frequency analysis revealed that these effects were mirrored in gain-related delta, but not in loss-related theta band activity, suggesting that people ascribed more value to high-effort outcomes. In addition, we also explored whether individual differences in behavioral effort discounting rates and reward sensitivity in the absence of effort may affect the relationship between effort exertion and subsequent reward processing. Together, our findings provide evidence that cognitive effort exertion can increase the subjective value of subsequent outcomes and that this effect may primarily rely on modulations of delta band activity.

Cross-modal contextual memory guides selective attention in visual-search tasks.

Visual search is speeded when a target item is positioned consistently within an invariant (repeatedly encountered) configuration of distractor items ("contextual cueing"). Contextual cueing is also observed in cross-modal search, when the location of the-visual-target is predicted by distractors from another-tactile-sensory modality. Previous studies examining lateralized waveforms of the event-related potential (ERP) with millisecond precision have shown that learned visual contexts improve a whole cascade of search-processing stages. Drawing on ERPs, the present study tested alternative accounts of contextual cueing in tasks in which distractor-target contextual associations are established across, as compared to, within sensory modalities. To this end, we devised a novel, cross-modal search task: search for a visual feature singleton, with repeated (and nonrepeated) distractor configurations presented either within the same (visual) or a different (tactile) modality. We found reaction times (RTs) to be faster for repeated versus nonrepeated configurations, with comparable facilitation effects between visual (unimodal) and tactile (crossmodal) context cues. Further, for repeated configurations, there were enhanced amplitudes (and reduced latencies) of ERPs indexing attentional allocation (PCN) and postselective analysis of the target (CDA), respectively; both components correlated positively with the RT facilitation. These effects were again comparable between uni- and crossmodal cueing conditions. In contrast, motor-related processes indexed by the response-locked LRP contributed little to the RT effects. These results indicate that both uni- and crossmodal context cues benefit the same, visual processing stages related to the selection and subsequent analysis of the search target.

Event-related potentials to acoustic startle probes during unpredictable threat are associated with individual differences in intolerance of uncertainty

Individual differences in sensitivity to unpredictable threat may be a critical mechanism for internalizing psychopathology phenotypes. The present study examined whether the startle probe-elicited N100 and P300 during unpredictable threat – two event-related potentials indexing early and elaborative attentional processing of unpredictable threat – may be endophenotypes for internalizing psychopathology, including fear and distress/misery disorders and intolerance of uncertainty (IU), a clinical trait that is transdiagnostically associated with internalizing disorders. A large sample of adult siblings (N = 375) completed the no, predictable, and unpredictable threat task, during which the N100 and P300 were recorded. Relative to the no threat condition, N100 was more strongly enhanced in anticipation of unpredictable than predictable threat while P300 was suppressed to both predictable and unpredictable threat. While neither N100 enhancement nor P300 suppression to unpredictable threat was associated with fear or distress/misery disorders, they were negatively linked to inhibitory IU (a facet of IU). Thus, individuals high in inhibitory IU showed reduced attentional engagement with the threatening context when it was unpredictable. Further, N100 enhancement and, to a lesser degree, P300 suppression to unpredictable threat showed familial aggregation – a key criterion for determining whether a biomarker is an endophenotype. In sum, N100 enhancement and P300 suppression to unpredictable threat may be endophenotypes for dimensional measures of internalizing psychopathology.

Relationship between Resting-State Alpha Coherence and Cognitive Control in Individuals with Internet Gaming Disorder: A Multimodal Approach Based on Resting-State Electroencephalography and Event-Related Potentials.

The human brain is constantly active, even at rest. Alpha coherence is an electroencephalography (EEG) rhythm that regulates functional connectivity between different brain regions. However, the relationships between resting-state alpha coherence and N2/P3 components associated with response inhibition and cognitive processes have not been investigated in addictive disorders. The present study investigated the relationships between alpha coherence during the resting state and N2/P3 components of event-related potentials during the Go/Nogo task in healthy controls (HCs) and patients with Internet gaming disorder (IGD). A total of 64 young adults (HC: n = 31; IGD: n = 33) participated in this study. Alpha coherence values at left fronto-central and bilateral centro-temporal electrode sites were significantly correlated with P3 latency in HCs, whereas inverse correlations were observed in patients with IGD. Furthermore, significant differences were observed in the correlation values between the groups. Our results suggest that patients with IGD lack dynamic interactions of functional connectivity between the fronto-centro-temporal regions during the resting state and the event-related potential (ERP) index during cognitive tasks. The findings of this study may have important implications for understanding the neurophysiological mechanisms linking resting-state EEG and task-related ERPs underlying IGD.