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Objective Neural hypo-sensitivity to cues predicting positive reinforcement has been observed in ADHD using the Monetary Incentive Delay (MID) task. Here we report the first study using an electrophysiological analogue of this task to distinguish between (i) cue related anticipation of reinforcement and downstream effects on (ii) target engagement and (iii) performance in a clinical sample of adolescents with ADHD and controls. Methods Thirty-one controls and 32 adolescents with ADHD aged 10–16 years performed the electrophysiological (e)-MID task − in which preparatory cues signal whether a response to an upcoming target will be reinforced or not − under three conditions; positive reinforcement, negative reinforcement (response cost) and no consequence (neutral). We extracted values for both cue-related potentials known to be, both, associated with response preparation and modulated by reinforcement (Cue P3 and Cue CNV) and target-related potentials (target P3) and compared these between ADHD and controls. Results ADHD and controls did not differ on cue-related components on neutral trials. Against expectation, adolescents with ADHD displayed Cue P3 and Cue CNV reinforcement-related enhancement (versus neutral trials) compared to controls. ADHD individuals displayed smaller target P3 amplitudes and slower and more variable performance − but effects were not modulated by reinforcement contingencies. When age, IQ and conduct problems were controlled effects were marginally significant but the pattern of results did not change. Discussion ADHD was associated with hypersensitivity to positive (and marginally negative) reinforcement reflected on components often thought to be associated with response preparation − however these did not translate into improved attention to targets. In the case of ADHD, upregulated CNV may be a specific marker of hyper-arousal rather than an enhancement of anticipatory attention to upcoming targets. Future studies should examine the effects of age, IQ and conduct problems on reinforcement sensitivity in ADHD. [ABSTRACT FROM AUTHOR]

Abstract: Children with autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) demonstrate face processing abnormalities that may underlie social impairment. Despite substantial overlap between ASD and ADHD, ERP markers of face and gaze processing have not been directly compared across pure and comorbid cases. Children with ASD (n =19), ADHD (n =18), comorbid ASD+ADHD (n =29) and typically developing (TD) controls (n =26) were presented with upright/inverted faces with direct/averted gaze, with concurrent recording of the P1 and N170 components. While the N170 was predominant in the right hemisphere in TD and ADHD, children with ASD (ASD/ASD+ADHD) showed a bilateral distribution. In addition, children with ASD demonstrated altered response to gaze direction on P1 latency and no sensitivity to gaze direction on midline-N170 amplitude compared to TD and ADHD. In contrast, children with ADHD (ADHD/ASD+ADHD) exhibited a reduced face inversion effect on P1 latency compared to TD and ASD. These findings suggest children with ASD have specific abnormalities in gaze processing and altered neural specialisation, whereas children with ADHD show abnormalities at early visual attention stages. Children with ASD+ADHD are an additive co-occurrence with deficits of both disorders. Elucidating the neural basis of the overlap between ASD and ADHD is likely to inform aetiological investigation and clinical assessment. [Copyright &y& Elsevier]

Abstract: Previous research has shown that eye gaze affects infants’ processing of novel objects. In the current study we address the question whether presenting a highly familiar face vs. a stranger enhances the effects of gaze cues on object processing in 4-month-olds. Infants were presented pictures of the infant''s caregiver and another infant''s caregiver (stranger) either turning eye gaze toward an object next to the face or looking away from the object. Then objects were presented again without the face and event-related potentials (ERP) were recorded. An enhanced positive slow wave (PSW) was found for objects that were not cued by the caregiver''s eye gaze, indicating that these objects required increased encoding compared to objects that were cued by the caregiver''s gaze. When a stranger was presented, a PSW was observed in response to objects regardless of whether the objects were gaze-cued or not. Thus, the caregiver''s eye gaze had a larger effect on infants’ object processing than the stranger''s gaze. This suggests that at 4 months of age the caregiver''s eye gaze is easier to process for infants, more salient, or both. The findings are discussed in terms of early social cognitive development and face processing models. [Copyright &y& Elsevier]

Automated systems for identifying and removing non-neural ICA components are growing in popularity among EEG researchers of adult populations. Infant EEG data differs in many ways from adult EEG data, but there exists almost no specific system for automated classification of source components from paediatric populations. Here, we adapt one of the most popular systems for adult ICA component classification for use with infant EEG data. Our adapted classifier significantly outperformed the original adult classifier on samples of naturalistic free play EEG data recorded from 10 to 12-month-old infants, achieving agreement rates with the manual classification of over 75% across two validation studies (n = 44, n = 25). Additionally, we examined both classifiers' ability to remove stereotyped ocular artifact from a basic visual processing ERP dataset compared to manual ICA data cleaning. Here, the new classifier performed on level with expert manual cleaning and was again significantly better than the adult classifier at removing artifact whilst retaining a greater amount of genuine neural signal operationalised through comparing ERP activations in time and space. Our new system (iMARA) offers developmental EEG researchers a flexible tool for automatic identification and removal of artifactual ICA components. • Currently, few tools are available for ICA based data correction that are designed around infant EEG. • ICA correction is necessary for naturalistic paradigms when movement artifacts covary with cognitive processes. • We present a system for automated ICA classification designed around infant EEG data. • This system offers increased performance compared to systems of automatic ICA classification designed around adult EEG. [ABSTRACT FROM AUTHOR]

[Display omitted] • We show repetition effects in event-related potentials across children and adults. • Repetition effects were related to specific item (but not mere category) memory. • Association of repetition effects and memory did not differ between age groups. • We demonstrate an age-independent neural indicator of high-fidelity memory encoding. The specificity with which past experiences can be remembered varies across the lifespan, possibly due to differences in how precisely information is encoded. Memory formation can be investigated through repetition effects, the common finding that neural activity is altered when stimuli are repeated. However, whether differences in this indirect measure of memory formation relate to lifespan differences in memory specificity has not yet been established. In the present study, we examined repetition effects in event-related potentials and their relation to recognition. During incidental encoding, children (aged 7–9 years), young adults (18–30 years), and older adults (65–76 years) viewed repeated object images from different categories. During subsequent recognition, we distinguished memory for the specific items versus the general categories. We identified repetition suppression in all age groups, and repetition enhancement for adults. Furthermore, individual item recognition performance comprising lure discrimination was positively associated with the magnitude of the neural repetition effects, which did not differ between groups, indicating common neural mechanisms of memory formation. Our findings demonstrate that neural repetition effects reflect the formation of highly specific memory representations and highlight their significance as a neural indicator of individual differences in episodic memory encoding across the lifespan. [ABSTRACT FROM AUTHOR]

Inhibitory control is a core executive function (EF) skill, thought to involve cognitive 'interference suppression' and motor 'response inhibition' sub-processes. A few studies have shown that early bilingualism shapes interference suppression but not response inhibition skills, however current behavioral measures do not fully allow us to disentangle these subcomponents. Lateralized Readiness Potentials (LRPs) are centroparietal event-related potentials (ERPs) that track motor response-preparations between stimulus-presentation and behavioral responses. We examine LRPs elicited during successful inhibitory control on a nonverbal Stroop task, in 6–8 year-old bilingual (n = 44) and monolingual (n = 48) children from comparable socio-economic backgrounds. Relative to monolinguals, bilinguals showed longer and stronger incorrect-response preparations, and a more mature pattern of correct-response preparation (shorter peak-latencies), underlying correct responses on Stroop-interference trials. Neural markers of response-inhibition were comparable between groups and no behavioral differences were found between-groups on the Stroop task. Results suggest group differences in underlying mechanisms of centroparietal motor-response preparation mechanisms in this age group, contrary to what has been shown using behavioral tasks previously. We discuss neural results in the context of speed-accuracy trade-offs. This is the first study to examine neural markers of motor-responses in bilingual children. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the relationship between the frequency of physical exercise and the ability to control negative emotions in adult women. On the basis of the pre-screening, 26 frequently active and 26 infrequently active young adult women (mean age = 22.9, and 23, respectively) were invited to participate in the study. We assessed their ability to control negative emotions using behavioral and electrophysiological measures during an emotion regulation task. To control negative emotions, participants were trained in reappraisal, a cognitive strategy which involves reinterpretation of emotional stimuli (here negative emotional pictures). Although no significant effects were observed in behavioral measures, the late positive potential (LPP, an electrophysiological marker of emotional response) showed that more frequently active group displayed better efficacy of negative emotion regulation (i.e., greater difference in response to reinterpreted vs passively watched negative pictures). This effect was further confirmed by a positive relationship between the frequency of physical exercise and the LPP index of reappraisal efficacy: the more frequently active the participants were, the larger the reappraisal efficacy they demonstrated. Overall, the study suggests that frequent physical exercise may lead to better efficacy of controlling negative emotions in women. • Frequent physical activity is associated with greater efficacy of reappraisal usage. • The effect was observed in electrophysiological but not in behavioral data. • The effect is not related to trait anxiety or habitual use of emotion regulation. [ABSTRACT FROM AUTHOR]

We investigated young infants' object encoding and processing in response to isolated eye gaze cues on the neural and behavioral level. In two experiments, 4-month-old infants watched a pair of isolated eyes gazing towards or away from novel objects. Subsequently, the same objects were presented alone (i.e., without eyes). We measured event-related potentials (ERP) in response to object-directed and object-averted eye gaze as well as to the subsequently presented isolated objects. Using eye-tracking methods, we additionally measured infants' looking behavior in reaction to the subsequently presented isolated objects. The ERP data revealed an enhanced slow wave positivity for object-directed eye gaze, indicating increased encoding of observed gaze cues. Regarding the objects, we found an enhanced Nc amplitude and increased looking times in response to previously uncued objects, indicating a novelty response on the neural and behavioral level. The results suggest that isolated eye gaze stimuli are sufficient to trigger object encoding and facilitate further object processing. [ABSTRACT FROM AUTHOR]