Error-related brain activity in extraverts: Evidence for altered response monitoring in social context

While the personality trait of extraversion has been linked to enhanced reward sensitivity and its putative neural correlates, little is known about whether extraverts’ neural circuits are particularly sensitive to social rewards, given their preference for social engagement and social interactions. Using event-related potentials (ERPs), this study examined the relationship between the variation on the extraversion spectrum and a feedback-related ERP component (the error-related negativity or ERN) known to be sensitive to the value placed on errors and reward. Participants completed a forced-choice task, in which either rewarding or punitive feedback regarding their performance was provided, through either social (facial expressions) or non-social (verbal written) mode. The ERNs elicited by error trials in the social – but not in non-social – blocks were found to be associated with the extent of one's extraversion. However, the directionality of the effect was in contrast with the original prediction: namely, extraverts exhibited smaller ERNs than introverts during social blocks, whereas all participants produced similar ERNs in the non-social, verbal feedback condition. This finding suggests that extraverts exhibit diminished engagement in response monitoring – or find errors to be less salient – in the context of social feedback, perhaps because they find social contexts more predictable and thus more pleasant and less anxiety provoking.     

Error negativity and response control

Error trials are associated with faster responses than correct trials in simple discrimination tasks suggesting that errors result from impulsive responding. We investigated the relationship between error negativity (Ne/ERN), an event-related potential associated with error detection, and two behavioral indices of response control: response time (RT) differences between incorrect and correct trials (an index of impulsivity) and percentage of errors. Response-locked ERPs were collected from 17 young adults during a visual flanker task. Consistent with previous findings, participants were significantly faster on error trials. However, participants who exhibited larger Ne/ERN peak amplitudes had significantly smaller RT differences, suggesting a more controlled response strategy. Furthermore, Ne/ERN latencies were positively associated with percentage of errors. These findings are consistent with the view that the Ne/ERN reflects the activity of a monitoring system that is closely linked to remedial systems responsible for individual differences in response control or impulsive behavior.     

The error-related negativity as a state and trait measure: motivation, personality, and ERPs in response to errors

This study examines changes in the error-related negativity (ERN/Ne) related to motivational incentives and personality traits. ERPs were gathered while adults completed a four-choice letter task during four motivational conditions. Monetary incentives for finger and hand accuracy were altered across motivation conditions to either be equal or favor one type of accuracy over the other in a 3:1 ratio. Larger ERN/Ne amplitudes were predicted with increased incentives, with personality moderating this effect. Results were as expected: Individuals higher on conscientiousness displayed smaller motivation-related changes in the ERN/Ne. Similarly, those low on neuroticism had smaller effects, with the effect of Conscientiousness absent after accounting for Neuroticism. These results emphasize an emotional/evaluative function for the ERN/Ne, and suggest that the ability to selectively invest in error monitoring is moderated by underlying personality.     

Speeding up older adults: age-effects on error processing in speed and accuracy conditions

Behavioral performance in older adults is often characterized by normal error rates but longer response latencies compared to younger adults. The slowing of reaction times might reflect a compensatory strategy to avoid errors and might be associated with performance monitoring alterations. The present study investigated whether the ability to compensate for potential deficits influences age-related differences in performance monitoring. A modified flanker task was used with either accuracy or speed instruction. Both groups showed reliable differences between conditions: accuracy, reaction times and error-related negativities were reduced in the speed compared with the accuracy condition. Older adults showed smaller error-related negativities compared with younger adults and the reduction was more pronounced in the speed condition. Further, similar-sized error-related and correct-related negativities were found in older adults. Results indicate that performance monitoring deficits in older adults are related to deficits in behavioral performance, at least if they are forced to respond quickly.     

Event-related brain potentials and error-related processing: An analysis of incorrect responses to go and no-go stimuli

Recent research has suggested that there is a component of the event-related brain potential, the error-related negativity (ERN), that is associated with error detection and remedial actions such as error inhibition, immediate error correction, or error compensation. The present experiment used a go/no-go task to define more precisely the functional significance of this component. In this task, an ERN was observed for incorrect responses on go trials (errors of choice) and for response on no-go trials (errors of action). Because errors of action cannot be corrected immediately by executing another response, these results indicate that the process manifested by the ERN is not dependent on immediate error correction. Other aspects of the data converge in suggesting that the ERN process is more U related to error detection and that the connections between detection and remedial actions may depend on the task situation.     

Single trial time-frequency domain analysis of error processing in post-traumatic stress disorder

Error processing studies in psychology and psychiatry are relatively common. Event-related potentials (ERPs) are often used as measures of error processing, two such response-locked ERPs being the error-related negativity (ERN) and the error-related positivity (Pe). The ERN and Pe occur following committed error in reaction time tasks as low frequency (4-8Hz) electroencephalographic (EEG) oscillations registered at the midline fronto-central sites. We created an alternative method for analyzing error processing using time-frequency analysis in the form of a wavelet transform. A study was conducted in which subjects with PTSD and healthy control completed a forced-choice task. Single trial EEG data from errors in the task were processed using a continuous wavelet transform. Coefficients from the transform that corresponded to the theta range were averaged to isolate a theta waveform in the time-frequency domain. Measures called the time-frequency ERN and Pe were obtained from these waveforms for five different channels and then averaged to obtain a single time-frequency ERN and Pe for each error trial. A comparison of the amplitude and latency for the time-frequency ERN and Pe between the PTSD and control group was performed. A significant group effect was found on the amplitude of both measures. These results indicate that the developed single trial time-frequency error analysis method is suitable for examining error processing in PTSD and possibly other psychiatric disorders.     

Error processing in high-functioning Autism Spectrum Disorders

Studies report error-processing abnormalities in high-functioning individuals with Autism Spectrum Disorders (ASD) that may be influenced by intelligence and autism severity. Error processing can be measured using the error-related negativity (ERN) and post-error positivity (Pe) components of the event-related potential (ERP), along with behavioral indices such as post-error reaction time (RT) slowing. We used a modified Flanker task to test the hypothesis that high-functioning individuals with ASD would show decreased amplitude ERN in 24 individuals with ASD and 21 age- and IQ-matched typically-developing control participants. Behaviorally, individuals with ASD committed more errors than controls, but groups did not significantly differ on RTs, although there was a trend-level difference in post-error slowing. For ERPs, ERN amplitude was significantly attenuated in individuals with ASD relative to controls; groups did not differ in Pe amplitude. Amplitude of the ERN was not significantly correlated with measures of intelligence, anxiety, behavioral inhibition, or general autism severity.     

Error-related brain potentials are differentially related to awareness of response errors: evidence from an antisaccade task

The error negativity (Ne/ERN) and error positivity (Pe) are two components of the event-related brain potential (ERP) that are associated with action monitoring and error detection. To investigate the relation between error processing and conscious self-monitoring of behavior, the present experiment examined whether an Ne and Pe are observed after response errors of which participants are unaware. Ne and Pe measures, behavioral accuracy, and trial-to-trial subjective accuracy judgments were obtained from participants performing an antisaccade task, which elicits many unperceived, incorrect reflex-like saccades. Consistent with previous research, subjectively unperceived saccade errors were almost always immediately corrected, and were associated with faster correction times and smaller saccade sizes than perceived errors. Importantly, irrespective of whether the participant was aware of the error or not, erroneous saccades were followed by a sizable Ne. In contrast, the Pe was much more pronounced for perceived than for unperceived errors. Unperceived errors were characterized by the absence of posterror slowing. These and other results are consistent with the view that the Ne and Pe reflect the activity of two separate error monitoring processes, of which only the later process, reflected by the Pe, is associated with conscious error recognition and remedial action.     

Error-related negativity varies with the activation of gender stereotypes

The error-related negativity (ERN) was suggested to reflect the response-performance monitoring process. The purpose of this study is to investigate how the activation of gender stereotypes influences the ERN. Twenty-eight male participants were asked to complete a tool or kitchenware identification task. The prime stimulus is a picture of a male or female face and the target stimulus is either a kitchen utensil or a hand tool. The ERN amplitude on male-kitchenware trials is significantly larger than that on female-kitchenware trials, which reveals the low-level, automatic activation of gender stereotypes. The ERN that was elicited in this task has two sources—operation errors and the conflict between the gender stereotype activation and the non-prejudice beliefs. And the gender stereotype activation may be the key factor leading to this difference of ERN. In other words, the stereotype activation in this experimental paradigm may be indexed by the ERN.     

Visual mismatch negativity: New evidence from the equiprobable paradigm

In visual oddball studies, deviant compared to standard stimuli elicited a posterior negative ERP at around 100–250 ms. To determine the underlying processes of the negativity, we used the equiprobable sequence in which bar stimuli of five types of orientation were presented with equal probabilities (control 20% each) as well as the oddball sequence in which two stimuli with the closest orientation were presented with different probabilities (deviant 20% and standard 80%). Deviant compared to standard stimuli elicited two negativities at around 100–150 ms with no hemispheric dominance and 200–250 ms with right hemispheric dominance, while deviant compared to control stimuli elicited only a negativity at around 200–250 ms with right hemispheric dominance. These results suggest that the early negativity reflects refractory effect, while the late negativity reflects memory-comparison-based change detection effect (visual mismatch negativity).     

Electrophysiological correlates of error correction

Evidence in the literature for the proposed relationship between the error-related negativity (ERN) and error correction is rather limited and inconsistent. We investigated corrective behavior and the ERN in two groups of participants who performed a flanker task. The correction-instructed group was asked to immediately correct all encountered errors. The noninstructed group was unaware that corrective responses were recorded. We found a negative deflection following corrected errors that peaked at 200-240 ms after the error. We refer to this negativity in the ERP waveform as correction-related negativity (CoRN). We assume that the correction-related negativity reflects evaluative functions of the motor system necessary for error corrections. ERN latency and amplitude were modulated by the occurrence and temporal characteristics of immediate corrections. These results are discussed within the framework of current models of performance monitoring.     

The effect of manipulating task difficulty on error-related negativity in individuals with obsessive-compulsive symptoms

Previous research has found that individuals with obsessive-compulsive (OC) symptoms show larger error-related negativity (ERN) and correct-response negativity (CRN) amplitudes than controls. Task difficulty was manipulated during a flanker task and a probabilistic learning task to determine the effect of difficulty on ERN and CRN amplitudes in those with high or low levels of OC symptoms. Increasing task difficulty during a flanker task attenuated ERN amplitudes and enhanced CRN amplitudes. Although larger ERN amplitudes were found in the high OC group compared to the low OC group during the easy flanker task, this group difference was no longer apparent during the difficult version of the flanker task. Increasing difficulty during the probabilistic learning task had no effect on group differences in ERN or CRN amplitudes. The results of this study suggest that the hyperactive error-monitoring activity associated with OC symptoms depends on the difficulty and type of task performed.     

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.     

Dissociation of Pe and ERN/Ne in the conscious recognition of an error

We evaluated the relationship between conscious awareness and the ERN/Ne and Pe in a digit entering task. On each trial, participants rated the accuracy of their responses on a three-point scale (incorrect, unsure, correct). The ERN/Ne was present on incorrect trials judged as incorrect. The Pe was evident on the same trials but also on correct and incorrect trials judged as unsure. We propose that the ERN/Ne occurs when there is an incorrect execution of a correct motor plan and the representation of the correct response is available for comparison with the actual response. The mismatch information that results from this comparison can be transferred to the Pe process and conscious awareness. However, the Pe process and conscious awareness do not only depend on this transfer of information from the ERN/Ne process. The Pe also occurs when there is uncertainty about the correctness of the motor plan, whether or not the plan is, in fact, correct.     

On the representation of words and nonwords in visual short-term memory: Evidence from human electrophysiology

Electrophysiological measures were used to investigate the contribution of lexical status on the maintenance of letter strings in visual short-term memory (VSTM). The sustained posterior contralateral negativity (SPCN), an electrophysiological marker of storage in VSTM, was measured for words and nonwords as well as scrambled letters. A smaller SPCN was found for words than for nonwords (independently of their pronounceability), indicating that lexical status influences storage in VSTM. One possibility is that words produce a smaller SPCN because they can be recoded to a form that does not require a low-level representation in VSTM. For exploratory purpose, a comparison between the nonwords and the scrambled nonwords was also made. Based on previous research, the SPCN component should not be affected by the size of the region enclosing to-be-encoded objects. Surprisingly, significant differences between the SPCN for nonwords and scrambled letters conditions were found, suggesting that special encoding mechanisms may be recruited to encode word-like letter strings.     

To err is autonomic: error-related brain potentials, ANS activity, and post-error compensatory behavior

A two-component event-related brain potential consisting of an error-related negativity (ERN/Ne) and positivity (Pe) has been associated with response monitoring and error detection. Both the ERN and Pe have been source-localized to the anterior cingulate cortex (ACC)--a frontal structure implicated in both cognitive and affective processing, as well as autonomic nervous system (ANS) modulation. The current study sought to examine the relationships among the ERN, the Pe, two autonomic measures, and behavior. Electroencephalogram (EEG), heart rate (HR), and skin conductance (SC) were recorded while subjects performed a two-choice reaction-time task. In addition to the characteristic ERN-Pe complex, errors were associated with larger SCRs and greater HR deceleration. The ERN correlated with the number of errors, but was unrelated to ANS activity and compensatory behavior. Pe, on the other hand, was correlated significantly with SCR, and both SCR and Pe were significantly correlated with post-error slowing.     

Comparison between mismatch negativity amplitude and magnetic mismatch field strength in normal adults

The auditory mismatch negativity (MMN) or its magnetic counterpart (magnetic mismatch field, MMF) has been widely used to assess the ability of stimulus-driven change detection process in humans. The authors evaluated the similarity of inter-individual variation of the response strength between MMN and MMF recordings. Three types of MMN or MMF were recorded in ten healthy subjects: change in duration of pure-tone stimuli, change in duration of the Japanese vowel /a/, and difference between the Japanese vowels /a/ and /o/. There was no significant correlation between MMN amplitude and MMF strength under any condition and in either hemisphere. These results suggest that widely used indices of MMN in the two technologies, i.e., EEG-amplitude and MEG-ECD may not be proportional in an individual. To further clarify the differential significance of recording MMN/MMF may be important to establish MMN/MMF as clinical indices of individual ability of preattentive stage of auditory processing.     

The brain regulation mechanism of error monitoring in impulsive children with ADHD—An analysis of error related potentials

The objective of this study was to investigate the brain mechanism involved in the regulation of impulsivity in children with Attention Deficit and Hyperactivity Disorder (ADHD) through error detection as well as error monitoring. The subjects in this study included 7–11-year-old impulsive ADHD children as well as normal children and adult controls. Error related negativity (ERN) and error positivity (Pe) were measured. ERN peak latency from the children groups was delayed significantly when compared with the adult group; however, no significant difference in ERN amplitude was found among the three groups. Impulsive ADHD children had the earliest peak latency of Pe. In addition, the average Pe amplitude in impulsive children was significantly smaller than in adults (Cz and Pz), and smaller than in normal children (Pz). Late conscious cognitive processing of error is significantly weaker in impulsive ADHD children, suggesting a serious deficit of late error monitoring, rather than error detection.     

Action monitoring in motor control: ERPs following selection and execution errors in a force production task

Action monitoring has been studied in many tasks by means of measuring the error-related negativity (Ne/ERN), but never in a motor control task requiring precise force production. Errors in discrete choice reaction tasks are the result of incorrect selections, but errors in force production can also arise from incorrect executions. ERPs were obtained while participants produced low or high isometric forces with their left or right hand. As expected, incorrect choices of hand elicited an Ne/ERN. Interestingly, Ne/ERNs were also present in the less discrete selection error of an incorrect choice of force, but only when erroneously a low instead of a high force was chosen. In both force ranges, no Ne/ERNs were found after errors in execution. These errors showed a large positivity in feedback ERPs and, similar to correct responses, a prolonged negativity in response ERPs. We propose that, compared to selection errors, the time uncertainty aspects of execution errors and the resulting changing response representations prohibit error detection by the internal monitoring system responsible for generating the Ne/ERN.     

The effect of erroneous responses on response monitoring in patients with major depressive disorder: a study with event-related potentials

Perceived failure is reported to have detrimental effects on subsequent performance in patients with major depressive disorder. We investigated the error-related negativity (ERN)/error negativity (Ne), an electrophysiological correlate of response monitoring, using a 64-channel EEG. Sixteen patients with DSM-IV major depressive disorder and 16 matched controls participated in an Eriksen flanker task with continuous performance feedback that signaled monetary reward. Compared to controls, patients with major depressive disorder showed a less negative ERN/Ne in error trials following error trials. This result might reflect impaired response monitoring processes in major depressive disorder resulting from an underactivity in a central reward pathway and/or a deficit in strategic reasoning.