In this systematic review and meta-analysis, the relationship between error awareness and the amplitude of Error-Related Negativity (ERN), a neural response to errors associated with cognitive control and error monitoring processes, was examined. Five studies published between 2010 and 2020, involving a total of 302 participants, were analyzed. Findings revealed a more pronounced negative amplitude of the ERN for aware errors compared to unaware errors, supporting the Error Detection Theory and Reinforcement Learning Theory. The results did not directly support or contradict the Conflict-Monitoring Theory. These findings underscore the critical role of conscious error detection in modulating ERN responses and adaptive behavioral modifications. However, due to the limited number of included studies and variability in their methodologies, caution is needed in interpreting the results. Future research should aim to validate these findings with larger samples and standardized study designs, while also exploring a more nuanced understanding of error awareness.

When researchers began addressing the electrophysiology of conscious error awareness more than a decade ago, the role of the error-related negativity (ERN), alongside the subsequently occurring error positivity (Pe), was an obvious locus of attention given the fact that they are taken as indices of cortical error processing. In contrast to the clear-cut findings that link the amplitude of the Pe to error awareness, the association between the ERN amplitude and error awareness is vastly unclear, with a range of studies reporting significant differences in the ERN amplitude with respect to error awareness, while others observing no modulation of the ERN amplitude. One problem in the studies obtaining null findings is the fact that conclusions are drawn based on small sample sizes, increasing the probability of type II error, especially given the fact that the ERN elicited using various error awareness paradigms tends to be small. The aim of the present study was to therefore address the issue of type II error in order to draw more certain conclusions about the modulation of the ERN amplitude by conscious error awareness. Forty participants performed a manual response inhibition task optimised to examine error awareness. While the early and late Pe amplitudes showed the expected sensitivity to error awareness, the ERN results depicted a more complex picture. The ERN amplitude for unaware errors appeared more negative than that of aware errors, both numerically and on the grand average ERP. The unexpected findings were explained in terms of (a) latency issues in the present data, (b) characteristics of the manual response inhibition task used and the possibility that it elicits variation in neurocognitive processing, and (c), in relation to possible contamination by the contingent negative variation (CNV), an ERP component elicited during response preparation. Suggestions for future research on how to address the issues raised in the present paper are also discussed.

Performance monitoring is a crucial metacognitive function that allows for adaptive behaviour. Electrophysiological studies on error monitoring specifically, have shown how error trials in different tasks elicit two distinct signatures, the error-related negativity (ERN) and the error positivity (Pe). While studies find a robust relation between error awareness and the Pe, results regarding error awareness and the ERN are more divergent. Also, no agreement has been reached on the mechanisms that elicit these signals. This meta-analysis aims to explore the relation between these electrophysiological signatures and error awareness and how disparities in study design might explain divergent study results. Two meta-analyses were conducted and found a significant effect-size for error awareness on both the ERN and the Pe. Subgroup analyses were conducted to explore how different study-characteristics can influence these outcomes. Although no effects were found, these results remain mainly inconclusive since the number of included studies was very low, and their study designs quite similar.

Moderate-to-severe traumatic brain injury (M/S TBI) is a growing public health concern with significant impact on the cognitive functioning of survivors. Cognitive control and deficits in awareness have been linked to poor recovery and rehabilitation outcomes. One way to research cognitive control is through awareness of errors using electroencephalogram and event-related potentials (ERPs). Both the error-related negativity and the post-error positivity components of the ERP are linked to error awareness and cognitive control processes. Attentional capacity and levels of apathy influence error awareness in those with M/S TBI. There are strong links between awareness, attention, and apathy. However, limited research has examined the role of attention, awareness, and apathy using electrophysiological indices of error awareness to further understand cognitive control in a M/S TBI sample. The current study sought to elucidate the role of apathy in error awareness in those with M/S TBI. Participants included 75 neurologically-healthy controls (divided randomly into two control groups) and 24 individuals with M/S TBI. All participants completed self-report measures of mood, apathy, and executive functioning, as well as a brief neuropsychological battery to measure attention and cognitive ability. To measure awareness, participants completed the error awareness task (EAT), a modified Stroop go/no-go task. Participants signaled awareness of errors committed on the previous trial. The M/S TBI group decreased accuracy while improving or maintaining error awareness compared to controls over time. There were no significant between-group differences for ERN and Pe amplitudes. Levels of apathy in the M/S TBI group were included in three multiple regression analyses predicting proportion of unaware errors, ERN amplitude, and Pe amplitude. Apathy was predictive of error awareness, although not in the predicted direction. Major analyses were replicated using two distinct control groups to determine potential sample effects. Results showed consistent results comparing both control groups to a M/S TBI group. Findings show variable levels of awareness and accuracy over time for those with M/S TBI when compared to controls. Conclusions include varying levels of attention and awareness from the M/S TBI group over time, evidenced by improving awareness of errors when they are happening, but an inability to regulate performance sufficiently to improve accuracy. Levels of apathy are playing a role in error awareness, however, not in predicted directions. The study provides support for the role of attentional impairments in error awareness and encourages future studies to look for varying levels of performance within a given task when using populations linked to elevated levels of apathy and attentional deficits.