Getting off track: Cortical feedback processing network modulated by continuous error signal during target-feedback mismatch.

Performance monitoring and feedback processing - especially in the wake of erroneous outcomes - represent a crucial aspect of everyday life, allowing us to deal with imminent threats in the short term but also promoting necessary behavioral adjustments in the long term to avoid future conflicts. Over the last thirty years, research extensively analyzed the neural correlates of processing discrete error stimuli, unveiling the error-related negativity (ERN) and error positivity (Pe) as two main components of the cognitive response. However, the connection between the ERN/Pe and distinct stages of error processing, ranging from action monitoring to subsequent corrective behavior, remains ambiguous. Furthermore, mundane actions such as steering a vehicle already transgress the scope of discrete erroneous events and demand fine-tuned feedback control, and thus, the processing of continuous error signals - a topic scarcely researched at present. We analyzed two electroencephalography datasets to investigate the processing of continuous erroneous signals during a target tracking task, employing feedback in various levels and modalities. We observed significant differences between correct (slightly delayed) and erroneous feedback conditions in the larger one of the two datasets that we analyzed, both in sensor and source space. Furthermore, we found strong error-induced modulations that appeared consistent across datasets and error conditions, indicating a clear order of engagement of specific brain regions that correspond to individual components of error processing.

Event-related potentials data quality in young children: Standardized measurement error of ERN and Pe.

Most methods used to quantify event-related potential (ERP) data were developed for use with typical adult populations. Questions regarding how these methods apply to child ERP data remain. Here, we focused on two widely used ERP scoring methods, namely, time-window mean amplitude and peak amplitude measures, for two ERP error monitoring components, the error-related negativity (ERN) and the error positivity (Pe), collected from Kindergarteners during a child-friendly cognitive control task (N = 170). We first established the presence of error-related ERPs and examined the relations between ERP scores and children's behavioral task performance. We then assessed the data quality (precision) of mean and peak ERP amplitude scores at the level of individual participants using the standardized measurement error of ERPs. We also compared the effects of choosing baseline correction periods that were relatively distal versus proximal to responses on data quality. Across each of these analyses, we found that time-window mean amplitude scoring was comparable to, and in some cases outperformed, peak amplitude scoring. In addition, the proximal baseline provided higher data quality than the distal baseline. We conclude with specific recommendations regarding the scoring and baseline correction for ERP data collected from young children.

A commentary on establishing norms for error-related brain activity during the arrow flanker task among young adults.

We suggest that a large data set for the error-related negativity (ERN) and error positivity (Pe) components of the scalp-recorded event-related brain potential (ERP) recently published as normative is not ready for such use in research and, especially, clinical application. Such efforts are challenged by an incomplete understanding of the functional significance of between-person differences in amplitudes and of nuisance factors that contribute to amplitude differences, a lack of standardization of methods, and the use of a convenience sample for the potentially normative database. To move ERPs toward standardization and useful norms, we encourage more research on the meaning of differences in ERN scores, including factors that influence between- and within-person variation, and the dissemination of protocols for data collection and processing.

Authors' reply to the commentary on "Establishing norms for error-related brain activity during the arrow Flanker task among young adults".

In their commentary on our article, "Establishing norms for error-related brain activity during the arrow Flanker task among young adults" (Imburgio et al., 2020), Clayson and colleagues (2021) voiced their concerns about our development of norms for an event-related potential measure of error monitoring, the error-related negativity (ERN). The central flaw in their commentary is the idea that because we don't know all the factors that can affect the ERN, it should not be normed. We respond to this idea, while also reiterating points made in our original manuscript: a) at present, the reported norms are not intended to be used for individual clinical assessment and b) our norms should be considered specific to the procedures (i.e., recording and processing parameters) and task used (i.e., arrow Flanker). Contrary to Clayson and colleagues' claims, we believe that information about the distribution of the ERN (i.e., our norms) in a large sample representative of those used in much of the ERN literature (i.e., unselected young adults) will be useful to the field and that this information stands to increase, not decrease, understanding of the ERN.

The influence of psychological and cognitive states on error-related negativity evoked during post-stroke rehabilitation movements.

BACKGROUND: Recently, error-related negativity (ERN) signals are proposed to develop an assist-as-needed robotic stroke rehabilitation program. Stroke patients' state-of-mind, such as motivation to participate and active involvement in the rehabilitation program, affects their rate of recovery from motor disability. If the characteristics of the robotic stroke rehabilitation program can be altered based on the state-of-mind of the patients, such that the patients remain engaged in the program, the rate of recovery from their motor disability can be improved. However, before that, it is imperative to understand how the states-of-mind of a participant affect their ERN signal. METHODS: This study aimed to determine the association between the ERN signal and the psychological and cognitive states of the participants. Experiments were conducted on stroke patients, which involved performing a physical rehabilitation exercise and a questionnaire to measure participants' subjective experience on four factors: motivation in participating in the experiment, perceived effort, perceived pressure, awareness of uncompleted exercise trials while performing the rehabilitation exercise. Statistical correlation analysis, EEG time-series and topographical analysis were used to assess the association between the ERN signals and the psychological and cognitive states of the participants. RESULTS: A strong correlation between the amplitude of the ERN signal and the psychological and cognitive states of the participants was observed, which indicate the possibility of estimating the said states using the amplitudes of the novel ERN signal. CONCLUSIONS: The findings pave the way for the development of an ERN based dynamically adaptive assist-as-needed robotic stroke rehabilitation program of which characteristics can be altered to keep the participants' motivation, effort, engagement in the rehabilitation program high. In future, the single-trial prediction ability of the novel ERN signals to predict the state-of-mind of stroke patients will be evaluated.

Enhanced error-related brain activations for mistakes that harm others: ERP evidence from a novel social performance-monitoring paradigm.

Our mistakes often have negative consequences for ourselves, but may also harm the people around us. Continuous monitoring of our performance is therefore crucial for both our own and others' well-being. Here, we investigated how modulations in responsibility for other's harm affects electrophysiological correlates of performance-monitoring, viz. the error-related negativity (ERN) and error positivity (Pe). Healthy participants (N = 27) performed a novel social performance-monitoring paradigm in two responsibility contexts. Mistakes made in the harmful context resulted in a negative consequence for a co-actor, i.e., hearing a loud aversive sound, while errors in the non-harmful context were followed by a soft non-aversive sound. Although participants themselves did not receive auditory feedback in either context, they did experience harmful mistakes as more distressing and reported higher effort to perform well in the harmful context. ERN amplitudes were enhanced for harmful compared to non-harmful mistakes. Pe amplitudes were unaffected. The present study shows that performing in a potentially harmful social context amplifies early automatic performance-monitoring processes and increases the impact of the resulting harmful mistakes. These outcomes not only further our theoretical knowledge of social performance monitoring, but also demonstrate a novel and useful paradigm to investigate aberrant responsibility attitudes in various clinical populations.

On the influence of informational content and key-response effect mapping on implicit learning and error monitoring in the serial reaction time (SRT) task.

The present experiment was designed to enhance our understanding of how response effects with varying amounts of useful information influence implicit sequence learning. We recorded event-related brain potentials, while participants performed a modified version of the serial reaction time task (SRTT). In this task, participants have to press one of four keys corresponding to four letters on a computer screen. Unknown to participants, in some parts of the experimental blocks, the stimuli appear in a repetitive (structured) deterministic sequence, whereas in other parts, stimuli were determined randomly. Four groups of participants differing in the presentation of tones after each response performed the SRTT. In the no tone group, no tones were presented after a response. The other three groups differed with respect to the melody generated by the key presses: in the unmelodic group, one out of four different tones was chosen randomly and presented immediately after a response. In the consistent melody group, the press of a response key always resulted in the production of the same tone, resulting in a repetitive melody during structured parts of the sequence (consistent redundant effect). In the inconsistent melody group, the "melody" produced in the sequenced parts of the blocks was identical to the consistent melody group, but the same response could produce two different tones depending on the actual position in the stimulus sequence. Thus, during structured sequences, subjects heard the same melody as in the consistent melody group, but every key press could be followed by one out of two different tones. To disentangle effects of sequence awareness from our experimental manipulations, all analyses were restricted to implicit learners. All four groups showed sequence learning, but to a different degree: in general, every kind of tone improved sequence learning relative to the no tone group. However, unmelodic tones were less beneficial for learning than tones forming a melody. Tones mapped consistently to response keys improved learning faster than tones producing the same melody, but not mapped consistently to keys. However, at the end of the learning phase, the two melody groups did not differ in the amount of sequence learning. The error-related negativity (ERN) increased with sequence learning (larger ERN at the end of the experiment for trials following the sequence compared to random trials) and this effect was more pronounced for the groups that showed more learning. These findings indicate that response effects containing useful information foster sequence learning even if the same response can produce different effects. Furthermore, we replicated earlier results showing that the importance of an error with respect to the task at hand modulates the activity of the human performance monitoring system.

Error-related brain activity dissociates hoarding disorder from obsessive-compulsive disorder.

BACKGROUND: Obsessive-compulsive disorder (OCD) is associated with an abnormally large error-related negativity (ERN), an electrophysiological measure of error monitoring in response to performance errors, but it is unclear if hoarding disorder (HD) also shows this abnormality. This study aimed to determine whether the neurophysiological mechanisms underlying error monitoring are similarly compromised in HD and OCD. METHOD: We used a visual flanker task to assess ERN in response to performance errors in 14 individuals with HD, 27 with OCD, 10 with HD+OCD, and 45 healthy controls (HC). Age-corrected performance and ERN amplitudes were examined using analyses of variance and planned pairwise group comparisons. RESULTS: A main effect of hoarding on ERN (p = 0.031) was observed, indicating ERN amplitudes were attenuated in HD relative to non-HD subjects. A group × age interaction effect on ERN was also evident. In HD-positive subjects, ERN amplitude deficits were significantly greater in younger individuals (r = -0.479, p = 0.018), whereas there were no significant ERN changes with increasing age in OCD and HC participants. CONCLUSIONS: The reduced ERN in HD relative to OCD and HC provides evidence that HD is neurobiologically distinct from OCD, and suggests that deficient error monitoring may be a core pathophysiological feature of HD. This effect was particularly prominent in younger HD participants, further suggesting that deficient error monitoring manifests most strongly early in the illness course and/or in individuals with a relatively early illness onset.

Temporal unpredictability increases error monitoring as revealed by EEG-EMG investigation.

Reacting in an unpredictable context increases error monitoring as evidenced by greater error-related negativity (ERN), an electrophysiological marker linked to an evaluation of response outcomes. We investigated whether ERN also increased when participants evaluated their responses to events that appeared in unpredictable versus predictable moments in time. We complemented electroencephalographic (EEG) analysis of cortical activity by measuring performance monitoring processes at the peripheral level using electromyography (EMG). Specifically, we used EMG data to quantify how temporal unpredictability would affect motor time (MT), the interval between the onset of muscle activity, and the mechanical response. MT increases following errors, indexing online error detection, and an attempt to stop incorrect actions. In our temporally cued version of the stop-signal task, symbolic cues predicted (temporally predictable condition) or not (temporally unpredictable condition) the onset of a target. In 25% of trials, an auditory signal occurred shortly after the target presentation, informing participants that they should inhibit their response completely. Response times were slower, and fewer inhibitory errors were made during temporally unpredictable than predictable trials, indicating enhanced control of unwanted actions when target onset time was unknown. Importantly, the ERN to inhibitory errors was greater in temporally unpredictable relative to temporally predictable conditions. Similarly, EMG data revealed prolonged MT when reactions to temporally unpredictable targets had not been stopped. Taken together, our results show that a temporally unpredictable environment increases the control of unwanted actions, both at cortical and peripheral levels, suggesting a higher subjective cost of maladaptive responses to temporally uncertain events.

Task-specific relationships between error-related ERPs and behavior: Flanker, Stroop, and Go/Nogo tasks.

Performance monitoring has been widely studied during different forced-choice response tasks. Participants typically show longer response times (RTs) and increased accuracy following errors, but there are inconsistencies regarding the connection between error-related event-related brain potentials (ERPs) and behavior, such as RT and accuracy. The specific task in any given study could contribute to these inconsistencies, as different tasks may require distinct cognitive processes that impact ERP-behavior relationships. The present study sought to determine whether task moderates ERP-behavior relationships and whether these relationships are robustly observed when tasks and stimuli are treated as random effects. ERPs and behavioral indices (RTs and accuracy) recorded during flanker, Stroop, and Go/Nogo tasks from 180 people demonstrated a task-specific effect on ERP-behavior relationships, such that larger previous-trial error-related negativity (ERN) predicted longer RTs and greater likelihood of a correct response on subsequent trials during flanker and Stroop tasks but not during Go/Nogo task. Additionally, larger previous-trial error positivity (Pe) predicted faster RTs and smaller variances of RTs on subsequent trials for Stroop and Go/Nogo tasks but not for flanker task. When tasks and stimuli were treated as random effects, ERP-behavior relationships were not observed. These findings support the need to consider the task used for recording performance monitoring measures when interpreting results across studies.

Not all errors are created equally: specific ERN responses for errors originating from distractor-based response retrieval.

The binding of stimulus (S) and response (R) features into S-R episodes or 'event files' is a basic process for the regulation of behavior. Recent studies have shown that even irrelevant information is bound into event files. Associating distractors with responses leads to more efficient behavior if irrelevant and relevant stimuli are correlated, but leads to erroneous or inadequate behavior if irrelevant stimuli do not predict relevant ones. In this study, we investigated a control mechanism that is triggered by errors resulting from distractor-based response retrieval. We tested whether the error-related negativity (ERN) differs depending on the error source. In particular, we compared errors due to distractor-based response retrieval with random errors. Errors originating from distractor-based response retrieval elicited a stronger (more negative) ERN than did other types of errors, suggesting that the cognitive system responds in a unique way to this kind of error. This control mechanism is adaptive because it prevents the emergence of inadequate response routines.

Hormonal status effects on the electrophysiological correlates of performance monitoring in women.

Fluctuations in ovarian hormones are thought to play a role in the increased prevalence of mood and anxiety disorders in women. Error-related negativity (ERN) and error positivity (Pe) are two putative electrophysiological biomarkers for these internalizing disorders. We investigated whether female hormonal status, specifically menstrual cycle phase and oral contraceptive (OC) use, impact ERN and Pe. Additionally, we examined whether the relationship between the ERN and negative affect (NA) was moderated by hormonal status and tested whether the ERN mediated the relation between ovarian hormones and NA. Participants were healthy, pre-menopausal women who were naturally cycling (NC) or using OCs. Using a counterbalanced within-subject design, all participants performed a speeded-choice reaction-time task twice while undergoing electroencephalography measurements. NC women (N = 42) performed this task during the early follicular and midluteal phase (when estrogen and progesterone are both low and both high, respectively), while OC users (N = 42) performed the task during active OC use and during their pill-free week. Estradiol and progesterone levels were assessed in saliva. Comparing the two cycle phases within NC women revealed no differences in the (Δ)ERN, (Δ)Pe or NA. We did observe a negative relation between phase-related changes in the ΔERN and changes in NA. Mediation analysis additionally showed that phase-related changes in estradiol were indirectly and negatively related to NA through a reduction of ΔERN amplitudes. When comparing active OC users with NC women, we observed increased ΔPe- but not (Δ)ERN amplitudes in the former group. No evidence was found for moderating effects of menstrual cycle phase or OC use on the relation between the ERN and NA. These findings suggest that hormonal status may impact the neural correlates of performance monitoring and error sensitivity, and that this could be a potential mechanism through which ovarian hormones influence mood.

Associations of neural error-processing with symptoms and traits in a dimensional sample recruited across the obsessive-compulsive spectrum.

The error-related negativity (ERN), a neural response to errors, has been associated with several forms of psychopathology and assumed to represent a neural risk marker for obsessive-compulsive disorder (OCD) and anxiety disorders. Yet, it is still unknown which specific symptoms or traits best explain ERN variation. This study investigated performance-monitoring in participants (N = 100) recruited across a spectrum of obsessive-compulsive characteristics (n = 26 patients with OCD; n = 74 healthy participants including n = 24 with low, n = 24 with medium, and n = 26 with high OC-characteristics). Several compulsivity- and anxiety-associated characteristics were assessed and submitted to exploratory principal axis factor analysis. Associations of raw measures and derived factors with ERN and correct-related negativity (CRN) were examined. Patients with OCD showed increased ERN amplitudes compared to healthy participants. The ERN was associated with a variety of traits related to anxiety and negative affect. Factor analysis results revealed a most prominent association of the ERN with a composite measure of anxiety and neuroticism, whereas the CRN was specifically associated with compulsivity. Results support differential associations for the ERN and CRN and demonstrate that a dimensional recruitment approach and use of composite measures can improve our understanding of characteristics underlying variation in neural performance monitoring.

Bridging event-related potentials with behavioral studies in motor learning.

Behavioral approaches and electrophysiology in understanding human sensorimotor systems have both yielded substantial advancements in past decades. In fact, behavioral neuroscientists have found that motor learning involves the two distinct processes of the implicit and the explicit. Separately, they have also distinguished two kinds of errors that drive motor learning: sensory prediction error and task error. Scientists in electrophysiology, in addition, have discovered two motor-related, event-related potentials (ERPs): error-related negativity (ERN), and feedback-related negativity (FRN). However, there has been a lack of interchange between the two lines of research. This article, therefore, will survey through the literature in both directions, attempting to establish a bridge between these two fruitful lines of research.

Registered replication report of the construct validity of the error-related negativity (ERN): A multi-site study of task-specific ERN correlations with internalizing and externalizing symptoms.

Intact cognitive control is critical for goal-directed behavior and is widely studied using the error-related negativity (ERN). A common assumption in such studies is that ERNs recorded during different experimental paradigms reflect the same construct or functionally equivalent processes and that ERN is functionally distinct from other error-monitoring event-related brain potentials (ERPs; error positivity [Pe]), other neurophysiological indices of cognitive control (N2), and even other theoretically unrelated indices (visual N1). The present registered report represents a replication-plus-extension study of the psychometric validity of cognitive control ERPs and evaluated the convergent and divergent validity of ERN, Pe, N2, and visual N1 recorded during flanker, Stroop, and Go/no-go tasks. Data from 182 participants were collected from two study sites, and ERP psychometric reliability and validity were evaluated. Findings supported replication of convergent and divergent validity of ERN, Pe, and ΔPe (error minus correct)-these ERPs correlated more with themselves across tasks than with other ERPs measured during the same task. Convergent validity of ΔERN across tasks was not replicated, despite high internal consistency. ERN strongly correlated with N2 at levels similar or higher than those in support of convergent validity for other ERPs, and the present study failed to provide evidence of divergent validity for ERN and Pe from N2 or N1. ERN and ΔERN were unrelated to internalizing or externalizing symptoms. Findings underscore the importance of considering the psychometric validity of ERPs, as it provides a foundation for interpreting and comparing ERPs across tasks and studies.

Group differences in agency modulate error monitoring.

Mistakes can lead to aversive outcomes. Error monitoring may help prevent mistakes, but it might be maladaptive for individuals who lack control over aversive outcomes, as it consumes cognitive processing resources that could be allocated elsewhere. Here, we examined the effect of agency (i.e., control over punishment) on error monitoring using the error-related negativity (ERN), an event-related potential measure of error monitoring and error rate. Ninety unselected participants performed a flanker task in which they were shocked according to their own errors (controllable punishment, n = 47) or were shocked in accordance with another participant's errors (uncontrollable punishment, n = 43). Participants without agency over punishment showed smaller ERNs and higher error rates compared with participants with agency. Furthermore, punishment only reduced error rates for participants with agency. Together, these results provide the first experimental evidence that agency modulates error monitoring and suggest an adaptive process in which error monitoring is increased/decreased depending on its utility.

Modeling electrophysiological measures of decision-making and performance monitoring in neurotypical children engaging in a speeded flanker task.

This study aims to use structural equation modeling (SEM) to investigate the role of error processing in behavioral adaptation in children by testing relationships between error-related and stimulus-related event-related potentials (ERPs) obtained from two sessions of a speeded Eriksen flanker task. First, path models of averaged ERP components and mean response times (N1 â†’ P2 â†’ N2 â†’ P3 â†’ RTs) while controlling for trait effects, age, and sex, on each was examined separately for correct and incorrect trials from each session. While the model demonstrated acceptable fit statistics, the four models yielded diverse results. Next, path models for correct and incorrect trials were tested using latent variables defined by factoring together respective measures of ERP component amplitudes from each session. Comparison of correct and incorrect models revealed significant differences in the relationships between the successive measures of neural processing after controlling for trait effects. Moreover, latent variable models controlling for both trait and session-specific state variables yielded excellent model fit while models without session-specific state variables did not. In the final model, the error-related neural activity (i.e., the ERN and Pe) from incorrect trials was found to significantly relate to the stream of neural processes contributing to trials with the correct behavior. Importantly, the relationship between RT and error detection in the final model signifies a brain-and-behavior feedback loop. These findings provided empirical evidence that supports the adaptive orienting theory of error processing by demonstrating how the neural signals of error processing influence behavioral adaptations that facilitate correct behavioral performance.

Understanding the Error in Psychopathology: Notable Intraindividual Differences in Neural Variability of Performance Monitoring.

BACKGROUND: Abnormal performance monitoring is a possible transdiagnostic marker of psychopathology. Research on neural indices of performance monitoring, including the error-related negativity (ERN), typically examines group and interindividual (between-person) differences in mean/average scores. Intraindividual (within-person) variability in activity captures the capacity to dynamically adjust from moment to moment, and excessive variability appears maladaptive. Intraindividual variability in ERN represents a unique and largely unexamined dimension that might impact functioning. We tested whether psychopathology group differences (major depressive disorder, generalized anxiety disorder, obsessive-compulsive disorder) or corresponding psychiatric symptoms account for intraindividual variability in single-trial ERN scores. METHODS: High-density electroencephalogram was recorded during a semantic flanker task in 51 participants with major depressive disorder, 44 participants with generalized anxiety disorder, 31 participants with obsessive-compulsive disorder, and 56 psychiatrically healthy participants. Time-window mean ERN amplitude was scored 0-125 ms following participant response across four frontocentral sites. Multilevel location-scale models were used to simultaneously examine interindividual and intraindividual differences in ERN. RESULTS: Analyses indicated considerable intraindividual variability in ERN that was common across groups. However, we did not find strong evidence to support relationships between ERN and psychopathology groups or transdiagnostic symptoms. CONCLUSIONS: These findings point to important methodological implications for studies of performance monitoring in healthy and clinical populations-the common assumption of fixed intraindividual variability (i.e., residual variance) may be inappropriate for ERN studies. Implementation of multilevel location-scale models in future research can leverage between-person differences in intraindividual variability in performance monitoring to gain a rich understanding of trial-to-trial performance monitoring dynamics.

A dimensional approach to the neuronal correlates of anxiety, depression, and perfectionism: A transdiagnostic dissociation of error-related brain activity.

Transdiagnostic approaches such as the Research Domain Criteria (RDoC) highlight the importance of addressing psychopathological constructs dimensionally, since comorbidity and heterogeneity represent prevalent issues in the available categorical diagnosis. The current study analyses distinct internalizing dimensions of depression and anxiety, and the transdiagnostic feature of perfectionism on the modulation of error-related brain activity (i.e., ERN). A sample of 125 participants completed self-reported measures of anxiety, depression, and perfectionism, and performed two versions of the Flanker Task (performance monitoring and sustained-threat) during an EEG recording. In the broad internalizing dimensions, anxiety predicted increased ERN amplitudes when controlling for the shared variance with depression and perfectionism. The narrower dimensions of anxiety and depression revealed a dissociative effect: cognitive anxiety explained blunted ERN amplitudes, while the physiological signs of anxiety and depression predicted increased amplitudes. For perfectionism, no significant results were found. Exploratory analyses further revealed that the Error Positivity component (Pe) was reduced in anxiety and physiological depression. We conclude that anxiety features emerge as the main explanation for the altered patterns of error monitoring in a transdiagnostic sample. Since anxiety is expected to co-occur with other disorders, the current findings suggest that altered patterns of error monitoring will be a transdiagnostic feature of various internalizing and anxiety-related disorders.

Data quality and reliability metrics for event-related potentials (ERPs): The utility of subject-level reliability.

Event-related brain potentials (ERPs) represent direct measures of neural activity that are leveraged to understand cognitive, affective, sensory, and motor processes. Every ERP researcher encounters the obstacle of determining whether measurements are precise or psychometrically reliable enough for an intended purpose. In this primer, we review three types of measurements metrics: data quality, group-level internal consistency, and subject-level internal consistency. Data quality estimates characterize the precision of ERP scores but provide no inherent information about whether scores are precise enough for examining individual differences. Group-level internal consistency characterizes the ratio of between-person differences to the precision of those scores, and provides a single internal consistency estimate for an entire group of participants that risks masking low internal consistency for some individuals. Subject-level internal consistency considers the precision of an ERP score for a person relative to between-person differences for a group, and an estimate is yielded for each individual. We apply each metric to published error-related negativity (ERN) and reward positivity (RewP) data and demonstrate how failing to consider data quality and internal consistency can undermine statistical inferences. We conclude with general comments on how these estimates may be used to improve measurement quality and methodological transparency. Subject-level internal consistency computation is implemented within the ERP Reliability Analysis (ERA) Toolbox.