Stefon J.R. van Noordt

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.

Watch out! Medial frontal cortex is activated by cues signaling potential changes in response demands.

The human medial frontal cortex and especially the anterior cingulate cortex (ACC) have been implicated in several aspects of performance monitoring. We examined event-related EEG during a general process of controlling attention by using a novel paradigm to elicit a medial frontal negativity (MFN) to stimuli that indicate potential changes in future response demands. Independent components analysis revealed that the latent factors that accounted for MFN activity to such changes also accounted for activity associated with the error-related negativity and the NoGo inhibitory N2. Given that the medial frontal activation to these changes varied reliably across subjects simply as a function of potential need to alter responses in the absence of error commission and response inhibition, we propose that the underlying basis for medial frontal activation in situations demanding ongoing monitoring of performance involves an increase in attention control, a factor common to all MFN paradigms.

Mild head injury and sympathetic arousal: Investigating relationships with decision-making and neuropsychological performance in university students

Summary: The purpose of this study was to examine the relationships between neuropsychological performance, physiological arousal and decision-making in university students who have or have not reported a history of mild head injury (MHI). Methods: Forty-four students, 18 (41%) reporting a history of MHI, performed a design fluency task and the Iowa Gambling Task (IGT) while electrodermal activity (EDA) was recorded. Results: General cognitive ability and overall choice outcomes did not differ between groups. However, self-reported MHI severity predicted decision-making performance such that the greater the neural indices of trauma, the more disadvantageous the choices made by participants. As expected, both groups exhibited similar base levels of autonomic arousal and physiological responses to reward and punishment outcomes; however, those reporting MHI produced significantly lower levels of EDA during the anticipatory stages of decision-making. Conclusions: Overall, these findings encourage the acceptance of head injury as being on a continuum of brain injury severity, as MHI can emulate neurophysiological and neuropsychological features of more traumatic cases and may be impacting mechanisms which sustain adaptive social decision-making.

Reward feedback processing in children and adolescents: medial frontal theta oscillations.

We examined event-related electroencephalography (EEG) oscillations, including event-related spectral perturbations (ERSP) and intertrial coherence (ITC), to compare feedback processing during a chance-based reward vs. non-reward task in groups of 10-12-year-old (n=42), 13-14-year-old (n=34) and 15-17-year-olds (n=32). Because few, if any studies have applied these analytic methods to examine feedback processing in children or adolescents, we used a fine-grained approach that explored one half hertz by 16ms increments during feedback (no win vs. win events) in the theta (4-8Hz) frequency band. Complex wavelet frequency decomposition revealed that no win feedback was associated with enhanced theta power and phase coherence. We observed condition and age-based differences for both ERSP and ITC, with stronger effects for ITC. The transition from childhood to early adolescence (13-14yrs.) was a point of increased differentiation of ITC favoring no win vs. wins feedback and also compared to children or older adolescents, a point of heightened ITC for no win feedback (quadratic effect).

The political (and physiological) divide: Political orientation, performance monitoring, and the anterior cingulate response

Our goal was to test a model of sociopolitical attitudes that posits a relationship between individual differences in liberal versus conservative political orientation and differential levels of anterior cingulate cortex (ACC) responsivity. We recorded event-related potentials (ERPs) while participants who varied along a unidimensional liberal-conservative continuum engaged in a standard Go/NoGo task. We also measured component attitudes of political orientation in the form of traditionalism (degree of openness to social change) and egalitarianism (a preference for social equality). Generally, participants who reported a more liberal political orientation made fewer errors and produced larger ACC-generated ERPs (the error-related negativity, or ERN and the NoGo N2). This ACC activation, especially as indicated by a larger NoGo N2, was most strongly associated with greater preference for social equality. Performance accuracy, however, was most strongly associated with greater openness to social change. These data are consistent with a social neuroscience view that sociopolitical attitudes are related to aspects of neurophysiological responsivity. They also indicate that a bidimensional model of political orientation can enhance our interpretation of the nature of these associations.

Cognitive control in the eye of the beholder: Electrocortical theta and alpha modulation during response preparation in a cued saccade task

Abstract The oscillatory dynamics of medial frontal EEG theta and posterior alpha are implicated in the modulation of attention and cognitive control. We used a novel saccade cueing paradigm to examine whether theta and alpha are modulated by task difficulty during response preparation. After isolating and functionally classifying medial frontal and posterior alpha independent components, the EEG spectral power in these components was calculated on pro‐ and anti‐saccade trials prior to response probes. The results of bootstrap re‐sampling show that, compared to pro‐saccade trials, correct anti‐saccades are characterized by an increase in medial frontal theta and suppression of posterior alpha during the response preparation period. Furthermore, an absence of increased medial frontal theta prior to anti‐saccades probes occurs on error trials, that is, a failure to control pre‐potent eye movements. For these error trials, a burst in medial frontal theta is instead observed following error feedback. Our findings show that enhanced medial frontal theta is linked not only to dynamic cognitive control that is reactive (such as, after error commission), but is also an important prerequisite for success when behavioral control is challenged. HighlightsSaccade cueing paradigm to examine oscillatory dynamics of response preparation.Theta enhanced during response preparation on anti‐saccade correct trials.Alpha reduced during response preparation on anti‐saccade correct trials.Theta also increases following anti‐saccade errors.Medial frontal theta is important prerequisite for response control.

Moral decision-making in university students with self-reported mild head injury.

ABSTRACT Converging evidence shows that the prefrontal cortex is involved in moral decision-making. Individuals who have suffered injury to the ventromedial prefrontal cortex are more willing to endorse personal moral transgressions (e.g., make their decisions faster, and have attenuated sympathetic responses to those violations). We examined whether university students who have experienced a mild head injury (MHI), and are asymptomatic, present with a similar pattern of responding to moral dilemmas. Students reporting a history of MHI responded more quickly when making moral choices and exhibited less reticence toward the endorsement of personal moral transgressions than their non-MHI counterparts. Our results are consistent with studies involving persons with more serious, and evident, neuronal injury, and emphasize the important relationship between head injury and moral decision-making.

Inter-trial coherence of medial frontal theta oscillations linked to differential feedback processing in youth and young adults with autism

BACKGROUND Impairment in prediction and appreciation for choice outcomes could contribute to several core symptoms of ASD. We examined electroencephalography (EEG) oscillations in 27 youth and young adults diagnosed with autism spectrum disorder (ASD) and 22 IQ-matched neurotypical controls while they performed a chance-based reward prediction task. METHOD We re-analyzed our previously published ERP data (Larson et al., 2011) and examined theta band oscillations (4-8 Hz) at frontal midline sites, within a timing window that overlaps with the feedback-related negativity (FRN). We focused on event-related changes after presentation of feedback for reward (WIN) and punitive (LOSE) outcomes, both for spectral power and inter-trial phase coherence. RESULTS In our reward prediction task, for both groups, medial frontal theta power and phase coherence were greater following LOSE compared to WIN feedback. However, compared to controls, inter-trial coherence of medial frontal theta was significantly lower overall (across both feedback types) for individuals with ASD. Our results indicate that while individuals with ASD are sensitive to the valence of reward feedback, comparable to their neurotypical peers, they have reduced synchronization of medial frontal theta activity during feedback processing. CONCLUSIONS This finding are consistent with previous studies showing neural variability in ASD and suggest that the processes underlying decision-making and reinforcement learning may be atypical and less efficient in ASD.

STATSLAB: An open-source EEG toolbox for computing single-subject effects using robust statistics

ABSTRACT Research on robust statistics during the past half century provides concrete evidence that classical hypothesis tests that rely on the sample mean and variance are problematic. Even seemingly minor departures from normality are now known to create major problems in terms of increased error rates and decreased power. Fortunately, numerous robust estimation techniques have been developed that circumvent the need for strict assumptions of normality and equal variances, leading to increased power and accuracy when testing hypotheses. Two robust methods that have been shown to have practical value across a wide range of applied situations are the trimmed mean and percentile bootstrap test. To facilitate the uptake of robust methods into the behavioural sciences, especially when dealing with trial‐based data such as EEG, we introduce STATSLAB: An open‐source EEG toolbox for computing single‐subject effects using robust statistics. With the STATSLAB toolbox users can apply the percentile bootstrap test, with trimmed means, to a variety of neural signals including voltages, global field amplitude, and spectral features for both scalp channels and independent components. The toolbox offers a range of analytical strategies and is packaged with a fully functional graphical user interface that includes documentation.

Sleep Disturbances in Child and Adolescent Mental Health Disorders: A Review of the Variability of Objective Sleep Markers

Sleep disturbances are often observed in child and adolescent mental health disorders. Although previous research has identified consistent subjective reports of sleep disturbances, specific objective sleep markers have not yet been identified. We evaluated the current research on subjective and objective sleep markers in relation to attention deficit hyperactivity disorders, autism spectrum disorders, anxiety and depressive disorders. Subjective sleep markers are more consistent than objective markers of actigraphy, polysomnography, and circadian measures. We discuss the causes of variability in objective sleep findings and suggest future directions for research.