Tanja Endrass

Neural correlates of error awareness

Error processing results in a number of consequences on multiple levels. The posterior frontomedian cortex (pFMC) is involved in performance monitoring and signalling the need for adjustments, which can be observed as post-error speed-accuracy shifts at the behavioural level. Furthermore autonomic reactions to an error have been reported. The role of conscious error awareness for this processing cascade has received little attention of researchers so far. We examined the neural correlates of conscious error perception in a functional magnetic resonance imaging (fMRI) study. An antisaccade task known to yield sufficient numbers of aware and unaware errors was used. Results from a metaanalysis were used to guide a region of interest (ROI) analysis of the fMRI data. Consistent with previous reports, error-related activity in the rostral cingulate zone (RCZ), the pre-supplementary motor area (pre-SMA) and the insular cortex bilaterally was found. Whereas the RCZ activity did not differentiate between aware and unaware errors, activity in the left anterior inferior insular cortex was stronger for aware as compared to unaware errors. This could be due to increased awareness of the autonomic reaction to an error, or the increased autonomic reaction itself. Furthermore, post-error adjustments were only observed after aware errors and a correlation between post-error slowing and the hemodynamic activity in the RCZ was revealed. The data suggest that the RCZ activity alone is insufficient to drive error awareness. Its signal appears to be useful for post-error speed-accuracy adjustments only when the error is consciously perceived.

ERP correlates of conscious error recognition: aware and unaware errors in an antisaccade task

Event‐related potential (ERP) studies identified the error‐related negativity (Ne/ERN) and the error positivity (Pe) to be associated with performance errors. However, the functional significance of these components is not yet resolved. With the present study we intended to further investigate to what extent these components are related to error awareness. ERPs were recorded during an antisaccade task, and error awareness was obtained from accuracy ratings on each trial. In accordance with earlier findings, aware and unaware errors did not differ in Ne/ERN amplitude. Whereas the late Pe (400–600 ms) shows an increased parietal positivity for aware compared with unaware errors, the early Pe (200–300 ms) shows no dissociation between aware and unaware errors. These data lend further support to the view that the Ne/ERN and the (late) Pe reflect different processes in performance monitoring. In fact the present results provide a clear replication of [ S. Nieuwenhuis et al. (2001 ) Psychophysiology, 38, 752–760], showing that the Pe is associated with error awareness and remedial action. Furthermore, it has been shown that this is only true for the late Pe, whereas the early Pe like the Ne/ERN is not modulated by error awareness.

Overactive performance monitoring in obsessive-compulsive disorder: ERP evidence from correct and erroneous reactions.

Obsessive-compulsive disorder (OCD) has repeatedly been associated with hyperactivity in fronto-striatal brain regions and regions related to performance monitoring. The aim of the current study was to further investigate electrophysiological correlates of performance monitoring. Specifically, we intended to replicate previous results revealing enhanced error-related negativity (ERN) amplitudes in OCD patients. Furthermore, we examined whether OCD patients also showed alterations regarding the correct-related negativity (CRN), the error positivity (Pe) and behavioural correlates of performance monitoring. Event-related brain potentials (ERPs) were recorded from a group of 20 OCD patients and 20 healthy control participants during a modified flanker task. Force sensitive response buttons were utilized to separate correct trials from incorrect trials with full and partial response activation. Both groups displayed substantial ERN and Pe amplitudes for full and partial errors. On error trials OCD patients showed enhanced ERN amplitudes, but group differences were not significant for the Pe and for behavioural adjustment. Further, the OCD group also exhibited enhanced CRN amplitudes and a correlation of frontal CRN amplitudes with symptom severity. These data provide further support for the view that performance monitoring is overactive in OCD. Further, since the amplitude enhancement is not specific to error processing, but is also observed for correct reactions, a response monitoring or evaluation process that contributes to both ERP components might be overactive in OCD. This is in line with fMRI results that revealed higher error- and conflict-related activity in the medial frontal cortex in OCD patients.

Neural mechanisms and temporal dynamics of performance monitoring

Successful goal-directed behavior critically depends on performance monitoring, a set of cognitive and affective functions determining whether adaptive control is needed and, if so, which type and magnitude is required. Knowledge of the brain structures involved in such a process has grown enormously, although the time course of performance-monitoring (PM) activity remains poorly understood. Here, we review evidence from EEG recordings in humans and show that monitored events elicit a rather uniform sequence of cortical activity reflecting the detection, accumulation, and weighting of evidence for the necessity to adapt and (re)act. We link the EEG findings with invasive and pharmacological findings and evaluate the neurobiological plausibility of current theories of PM.

Overactive Error-Related Brain Activity as a Candidate Endophenotype for Obsessive-Compulsive Disorder: Evidence From Unaffected First-Degree Relatives

OBJECTIVE Hyperactivity in frontal-striatal circuits is assumed to be involved in the pathophysiology of obsessive-compulsive disorder (OCD). In line with that, electrocortical correlates of overactive performance monitoring have been found to be associated with OCD independent from symptom state. The purpose of the present study was to elucidate whether overactive performance monitoring may represent a candidate endophenotype for OCD. In this case, unaffected first-degree relatives of OCD patients should also show this trait. METHOD Amplitudes of the error-related negativity and the correct-related negativity in the event-related brain potential during a flanker task were used to assess performance monitoring in three carefully matched groups: 30 patients with OCD, 30 unaffected first-degree relatives of OCD patients, and 30 healthy comparison subjects. RESULTS Relative to the healthy comparison subjects, both unaffected first-degree relatives and OCD patients showed increased error-related brain potentials. No significant correlation was obtained between amplitudes and symptom severity measures, neither in patients nor in first-degree relatives. CONCLUSIONS Increased error-related brain potentials were observed not only in OCD patients but also in unaffected first-degree relatives. Overactive error monitoring may reflect a trait marker for OCD that is independent of the presence of clinical symptoms. Thus, enhanced error-related brain activity represents a candidate neurocognitive endophenotype for OCD.

Abnormally high degree connectivity of the orbitofrontal cortex in obsessive-compulsive disorder.

IMPORTANCE Neurobiological models of obsessive-compulsive disorder (OCD) predict hyperactivity in brain circuits involving the orbitofrontal cortex and the basal ganglia, but it is unclear whether these areas are also characterized by altered brain network properties. OBJECTIVES To determine regions of abnormal degree connectivity in patients with OCD and to investigate whether connectivity measures are affected by antidepressant medication in OCD. DESIGN Case-control cross-sectional study using resting-state functional magnetic resonance imaging and a data-driven, model-free method to test for alterations in the degree of whole-brain, distant, and local connectivity in unmedicated patients with OCD compared with healthy controls. SETTING Outpatient clinic for OCD. PARTICIPANTS Twenty-three patients with OCD (12 women, 11 men) receiving no medication, 23 patients with OCD (14 women, 9 men) treated with antidepressant medication, and 2 equally sized control samples matched for age, sex, handedness, educational level, and IQ. MAIN OUTCOME MEASURES Statistical parametric maps testing the degree of distant and local functional connectivity of each voxel (hub analysis at voxel level) and OCD symptom severity. RESULTS Unmedicated patients with OCD showed greater distant connectivity in the orbitofrontal cortex and subthalamic nucleus and greater local connectivity in the orbitofrontal cortex and the putamen. Furthermore, distant connectivity of the orbitofrontal cortex and the putamen positively correlated with global OCD symptom severity. Medicated patients with OCD showed reduced local connectivity of the ventral striatum compared with the unmedicated patients. CONCLUSIONS AND RELEVANCE Consistent with neurobiological models of OCD, the orbitofrontal cortex and the basal ganglia are hyperconnected in unmedicated patients. The finding of distant connectivity alterations of the orbitofrontal cortex and the basal ganglia represents initial evidence of greater connections with distant cortical areas outside of corticostriatal circuitry. Furthermore, these data suggest that antidepressant medication may reduce connectivity within corticobasal ganglia-thalamo-cortical circuits in OCD.

Performance monitoring and error significance in patients with obsessive-compulsive disorder

Performance monitoring has been consistently found to be overactive in obsessive-compulsive disorder (OCD). The present study examines whether performance monitoring in OCD is adjusted with error significance. Therefore, errors in a flanker task were followed by neutral (standard condition) or punishment feedbacks (punishment condition). In the standard condition patients had significantly larger error-related negativity (ERN) and correct-related negativity (CRN) ampliudes than controls. But, in the punishment condition groups did not differ in ERN and CRN amplitudes. While healthy controls showed an amplitude enhancement between standard and punishment condition, OCD patients showed no variation. In contrast, group differences were not found for the error positivity (Pe): both groups had larger Pe amplitudes in the punishment condition. Results confirm earlier findings of overactive error monitoring in OCD. The absence of a variation with error significance might indicate that OCD patients are unable to down-regulate their monitoring activity according to external requirements.

Error Awareness in a Saccade Countermanding Task

Abstract: Stop-signal tasks can be used to analyze mechanisms of action control and error monitoring. Previous event-related potential (ERP) studies indicated enhanced stop-signal N2 amplitudes for...

The ERN is the ERN is the ERN? Convergent validity of error-related brain activity across different tasks

Error-processing is increasingly examined using the error-related negativity (ERN) and error positivity (Pe) - event-related potentials (ERPs) that demonstrate trait-like properties and excellent reliability. The current study focuses on construct validity by applying a multitrait-multimethod approach, treating error-related ERPs (i.e., ERN, Pe and the difference between error minus correct, referred to as ΔERN and ΔPe, respectively) as traits measured across multiple tasks (i.e., Flanker, Stroop, and Go/NoGo). Results suggest convergent validity of these ERPs ranging between .62 and .64 for ΔERN. Values were somewhat smaller for ERN (range .33-.43), Pe (range .37-.49) and ΔPe (range .30-.37). Further, the correlations for ERN and Pe are higher within components across tasks than between different components suggesting discriminant validity. In conclusion, the present study revealed evidence for convergent and discriminant validity of error-related ERPs, further supporting the use of these components as psychophysiological trait markers.

Punishment has a lasting impact on error‐related brain activity

The current study examined whether punishment has direct and lasting effects on error-related brain activity, and whether this effect is larger with increasing trait anxiety. Participants were told that errors on a flanker task would be punished in some blocks but not others. Punishment was applied following 50% of errors in punished blocks during the first half of the experiment (i.e., acquisition), but never in the second half (i.e., extinction). The ERN was enhanced in the punished blocks in both experimental phases--this enhancement remained stable throughout the extinction phase. More anxious individuals were characterized by larger punishment-related modulations in the ERN. The study reveals evidence for lasting, punishment-based modulations of the ERN that increase with anxiety. These data suggest avenues for research to examine more specific learning-related mechanisms that link anxiety to overactive error monitoring.