ERP study on the associations of peripheral oxytocin and prolactin with inhibitory processes involving emotional distraction.

BACKGROUND: Child maltreatment is a major health and social welfare problem, with serious and longstanding consequences. Impulse control ability plays an important role in reducing the risk of child maltreatment. The aim of this study was to investigate the associations of oxytocin (OXT) and prolactin (PRL) with behavior inhibition using children's facial expressions (angry or neutral) as emotional distractions. This may clarify a part of the neuroendocrinological mechanism that modulates impulse control ability in the context of child caregiving. METHODS: Participants were 16 females who had never been pregnant. Following venous blood sampling for OXT and PRL levels, participants performed an emotional Go/Nogo task during their follicular and luteal phases to test inhibitory control ability. Behavioral performance and event-related potentials (ERPs) during the task were measured. RESULTS: The results showed that there were significant fixed effects of OXT on behavioral performance, as measured by sensitivity (d-prime). This suggests that high peripheral OXT levels may be associated with better performance on the emotional Go/Nogo task, regardless of emotional distractors. PRL was associated with inhibitory processes as reflected by the Nogo-N2 and Nogo-P3. Particularly, high PRL levels were associated with the Nogo-N2 latency extension with the emotional distractors. CONCLUSIONS: Our findings suggest that OXT might be associated with improving behavioral performance regardless of emotional processes. It is suggested that processes related to PRL are related to premotor activities of behavioral inhibitions and emotions.

Attention cognitive deficiency in 6-8-year-old children with sleep disordered breathing:an ERP study / 中华行为医学与脑科学杂志

Objective To investigate the cognitive dificiency characteristics and the neuro electrophysiological mechanism of sleep disordered breathing(SDB) in school-age children.Methods20 cases of SDB children and 20 cases of normal group at 6-8 years old participated in the continue performance test(CPT-AX).The amplitude and latency of N2,P3 of event related potentials(ERPs) were measured and analysed at Fz leads,and the behavioral results were recorded at the same time.ResultsThere were no significant differences between SDB group and normal group in behavioral correct number (36.10±4.69 vs 35.05±3.49),the reaction time ((523.77±68.73)ms vs (496.59±78.65)ms) and false alarm number (1.0 (0.25,3.75) vs 0.5 (0.00,3.00))(all P>0.05).The SDB group showed significant increase in Go-P3 amplitudes compared with the normal group((10.25±6.46)μV vs (6.56±4.63)μV,P<0.05).The Go-P3 latency in SDB group was significantly prolonged than that in the normal group((438.80±59.72)ms vs (406±36.30)ms,P<0.05),and the Nogo-N2 amplitude in SDB group significantly decreased compared with the normal group ((-12.46±4.75)μV vs (-15.50±3.82)μV,P<0.05).ConclusionThe children aged 6 to 8 years old with sleep disordered breathing consume more resources and time to complete the attention process,like a compensatory response.And during the monitoring process there is a resource shortage that results in obvious defect in process of inhibition.

The impact of mental workload on inhibitory control subprocesses.

The inhibition of inappropriate responses is a function known to rely on prefrontal cortex (PFC) functioning. Similarly, working memory processes are known to rely on the PFC. Even though these processes are usually closely intertwined and the functional neuroanatomy underlying these processes is largely overlapping, the influence of working memory load on inhibitory control process has remained largely elusive. In the current study, we therefore examine how response inhibition processes are modulated by working memory load. For this, we systematically increased the working memory load of participants by integrating mental rotation processes in a Go/NoGo paradigm. To examine the system neurophysiology of these processes in detail, and to examine whether there are differential effects of working memory load on distinct response inhibition subprocesses, we applied event-related potentials (ERPs) in combination with source localization techniques. The data shows that after exceeding a certain threshold, inhibitory control processes are aggravated by working memory load. The neurophysiological data paralleled the behavioral data. However, it suggests that distinguishable response inhibition subprocesses are differentially modulated by working memory load: Changes were evident in the NoGo-P3 amplitude but not in the NoGo-N2 amplitude. On a system level, this distinctive modulation of response inhibition subprocesses was related to differences in neural activity in the left inferior and middle frontal gyri. We show that inhibitory control processes are impaired when the working memory load surpasses a certain threshold. This, however only applies to situations in which the necessity of inhibitory control processes cannot be easily detected on the basis of perceptual factors.

An exploratory analysis of Go/Nogo event-related potentials in major depression and depression following traumatic brain injury.

Rates of major depressive disorder (MDD) following traumatic brain injury (TBI) are estimated to be between 20% and 45%, a higher prevalence than that seen in the general population. These increased rates may be due to specific changes in brain function following TBI. Event related potentials (ERPs) are well suited for measuring the electrophysiological differences between groups in areas of cognitive processing impaired in both MDD and TBI, such as response inhibition. The current study presented an emotional Go/Nogo task (with schematic emotional faces as stimuli) to participants with TBI, participants with MDD, and participants with both TBI and MDD (TBI-MDD). Topographical distribution of activity and global field power comparisons were made across stimulus-locked epochs between these groups and healthy controls. The results indicated that ERPs were not altered by TBI alone. Both MDD and TBI-MDD groups showed similar alterations in topographical distribution and global field power in the N2 window, as well as late epoch alterations. The MDD and TBI-MDD groups showed significantly less fronto-central negativity during the N2 window in Nogo trials compared with the control group. The MDD and TBI-MDD groups also showed significantly less global field power in Nogo trials than Go trials during the N2 window while the control group showed the opposite pattern. The MDD and TBI-MDD groups showed no mood-congruent bias in behavioural or ERP measures. The results suggest that TBI-MDD displays similar electrophysiological changes to those found in the MDD group without TBI.

Neural mechanisms underlying conflict monitoring over risky decision alternatives: evidence from ERP in a Go/Nogo task.

This study assessed conflict monitoring during presentation of risky decision alternatives, as indexed by the Nogo-N2, Nogo-P3, N2d and P3d event-related potentials (ERP). Decision-makers were tested on a Go/Nogo gambling task in which gain/loss outcomes as well as stimulus type (Go/Nogo) were equiprobable. Frontal-central Nogo-N2 and Nogo-P3 did not significantly differ across risky decision alternatives, whereas N2d and P3d amplitudes were more sensitive to the nature of risky decision alternatives. Frontal-central N2d was moderated by the magnitude of alternatives, with N2d amplitude greater for large than small alternatives, a result that suggests a greater degree of conflict monitoring for the former. Central P3d was associated with alternative valence, such that P3d amplitude was greater for loss than gain valences, again suggestive of more conflict monitoring for the former. The N2d and P3d potentials in risky decision alternatives are discussed in terms of the functional significance of the N2/P3 complex.

Response inhibition is modulated by functional cerebral asymmetries for facial expression perception.

The efficacy of executive functions is critically modulated by information processing in earlier cognitive stages. For example, initial processing of verbal stimuli in the language-dominant left-hemisphere leads to more efficient response inhibition than initial processing of verbal stimuli in the non-dominant right hemisphere. However, it is unclear whether this organizational principle is specific for the language system, or a general principle that also applies to other types of lateralized cognition. To answer this question, we investigated the neurophysiological correlates of early attentional processes, facial expression perception and response inhibition during tachistoscopic presentation of facial "Go" and "Nogo" stimuli in the left and the right visual field (RVF). Participants committed fewer false alarms after Nogo-stimulus presentation in the left compared to the RVF. This right-hemispheric asymmetry on the behavioral level was also reflected in the neurophysiological correlates of face perception, specifically in a right-sided asymmetry in the N170 amplitude. Moreover, the right-hemispheric dominance for facial expression processing also affected event-related potentials typically related to response inhibition, namely the Nogo-N2 and Nogo-P3. These findings show that an effect of hemispheric asymmetries in early information processing on the efficacy of higher cognitive functions is not limited to left-hemispheric language functions, but can be generalized to predominantly right-hemispheric functions.

Performance monitoring and the medial prefrontal cortex: a review of individual differences and context effects as a window on self-regulation.

The medial prefrontal cortex (MPFC) is central to self-regulation and has been implicated in generating a cluster of event-related potential components, collectively referred to as medial frontal negativities (MFNs). These MFNs are elicited while individuals monitor behavioral and environmental consequences, and include the error-related negativity, Nogo N2, and the feedback-related negativity. A growing cognitive and affective neuroscience literature indicates that the activation of the anterior cingulate cortex (ACC) and surrounding medial prefrontal regions during performance monitoring is not only influenced by task context, but that these patterns of activity also vary as a function of individual differences (e.g., personality, temperament, clinical and non-clinical symptomatology, socio-political orientation, and genetic polymorphisms), as well as interactions between individual differences and task context. In this review we survey the neuroscience literature on the relations between performance monitoring, personality, task context, and brain functioning with a focus on the MPFC. We relate these issues to the role of affect in the paradigms used to elicit performance-monitoring neural responses and highlight some of the theoretical and clinical implications of this research. We conclude with a discussion of the complexity of these issues and how some of the basic assumptions required for their interpretation may be clarified with future research.

Response inhibition is linked to emotional devaluation: behavioural and electrophysiological evidence.

To study links between the inhibition of motor responses and emotional evaluation, we combined electrophysiological measures of prefrontal response inhibition with behavioural measures of affective evaluation. Participants first performed a Go-Nogo task in response to Asian and Caucasian faces (with race determining their Go or Nogo status), followed by a trustworthiness rating for each face. Faces previously seen as Nogo stimuli were rated as less trustworthy than previous Go stimuli. To study links between the efficiency of response inhibition in the Go-Nogo task and subsequent emotional evaluations, the Nogo N2 component was quantified separately for faces that were later judged to be high versus low in trustworthiness. Nogo N2 amplitudes were larger in response to low-rated as compared to high-rated faces, demonstrating that trial-by-trial variations in the efficiency of response inhibition triggered by Nogo faces, as measured by the Nogo N2 component, co-vary with their subsequent affective evaluation. These results suggest close links between inhibitory processes in top-down motor control and emotional responses.