Research using psychophysiological methods holds great promise for refining clinical assessment, identifying risk factors, and informing treatment. Unfortunately, unique methodological features of existing approaches limit inclusive research participation and, consequently, generalizability. In this brief overview and commentary, we provide a snapshot of the current state of representation in clinical psychophysiology with a focus on the forms and consequences of ongoing exclusion of Black participants. We illustrate issues of inequity and exclusion that are unique to clinical psychophysiology and consider intersections among social constructions of Blackness and biased design of current technology used to measure electroencephalography, skin conductance, and other signals. We then highlight work by groups dedicated to quantifying and addressing these limitations. We discuss the need for reflection and input from a wider variety of affected individuals to develop and refine new technologies given the risk of further widening disparities. Finally, we provide broad recommendations for clinical-psychophysiology research.
Affective science research on reward processing has primarily focused on monetary rewards. There has been a growing interest in evaluating the neural basis of social decision-making and reward processing. The present study employed a within-subject design and compared the reward positivity (RewP), an event-related potential component that is present following favorable feedback and absent or reduced following unfavorable feedback, during monetary and social reward tasks. Specifically, 114 participants (75 females) completed a monetary reward task and a novel social reward task that were matched on trial structure, timing, and feedback stimuli in a counterbalanced order. Results indicated that the monetary and social RewP were of similar magnitude, positively correlated and demonstrated comparable psychometric properties, including reliability and dependability. Across both the monetary and social tasks, women demonstrated a greater RewP compared with men. This study provides a novel methodological approach toward examining the electrocortical response to social reward that is comparable to monetary reward.
The error-related negativity (ERN) is a response-locked component in the event-related potential observed as a negative deflection 50-100 ms following the commission of an error. An unpredictable context has been shown to potentiate amygdala activity, attentional bias toward threat, and the ERN in adults. However, it is unclear whether the impact of unpredictability on the ERN is also observed in children and adolescents. In a sample of 32 9-17 year-old participants, we examined the influence of a task-irrelevant unpredictable context on neural response to errors. Participants completed a flanker task designed to elicit the ERN, while simultaneously being exposed to task-irrelevant tone sequences with either predictable or unpredictable timing. Unpredictable tones were rated as more anxiety provoking compared to the predictable tones. Fewer errors were made during unpredictable relative to predictable tones. Moreover, the ERN-but not the correct response negativity (CRN) or stimulus-locked N200-was potentiated during the unpredictable relative to predictable tones. The current study replicates and extends previous findings by demonstrating that an unpredictable context can increase task performance and selectively potentiate the ERN in children and adolescents. ERN magnitude can be modulated by environmental factors suggesting enhanced error processing in unpredictable contexts.
Reduced habituation to aversive stimuli has been observed during adolescence and may reflect an underlying mechanism of vulnerability for anxiety disorders. This study examined the startle reflex during a fear-learning task in 54 8-14-year-old girls. We examined the relationship between mean startle, startle habituation, pubertal development, and two measures linked to risk for anxiety: behavioral inhibition system (BIS) and the error-related negativity (ERN). Puberty, BIS, and the ERN were unrelated to mean startle; however, each measure modulated startle habituation. Greater pubertal development was associated with reduced startle habituation across the CS+ and CS-. Higher BIS related to a larger ERN, and both were associated with reduced startle habituation specifically to the CS+. All effects were independent of each other. Findings suggest that puberty alters habituation of defense system activation to both threat and safety cues, and this is independent of risk for anxiety, which uniquely impacts habituation to threat cues.
Growing evidence indicates that the amygdala contributes to processing both emotional stimuli and highly vivid episodic memories. The present research used event-related potentials (ERPs) to examine the individual and joint contributions of these dimensions on the neural responses to naturalistic stimuli, namely, autobiographical memories, which vary in terms of associated emotion and the vividness of recollection. In Experiment 1, participants recalled positive and negative personal memories, and memories for which no mention of emotion was made. Events recollected with high vividness showed no effect of emotion, whereas ERPs for events recollected with low vividness differed for both positive and negative memories versus non-emotional memories. The conjoint effects of emotion and vividness reflect the correlation of these variables in everyday life: more emotional memories are more vividly recalled. In Experiment 2, we pursued the interaction of emotion and vividness by asking participants to recall negative high-arousal, negative low-arousal, and emotionally neutral memories. Processing differed by vividness but not by emotion condition. The research implies that focus on the emotional valence associated with a memory, without conjoint consideration of how vividly it is recalled, neglects a critical determinant of neural processes that are modulated by the amygdala during recall of autobiographical memories.
The error-related negativity (ERN) is an electrophysiological response to errors. Individual differences in the ERN have been posited to reflect sensitivity to threat and linked with risk for anxiety disorders. Attention bias modification is a promising computerized intervention that has been shown to decrease threat biases and anxiety symptoms. In the present study, we examined the impact of a single session of attention bias modification, relative to a control task, on the neural correlates of response monitoring, including the ERN, correct response negativity (CRN), and their difference (i.e., the ERN - CRN or Delta ERN). The final sample included 60 participants who first completed a flanker task to elicit the ERN and CRN, and were then randomly assigned to attention bias modification (n = 30) or a control task (n = 30). After completing the attention bias modification or control task, participants completed the same flanker task to again elicit the ERN and CRN. Among participants who completed attention bias modification training, the ERN, CRN, and Delta ERN decreased from the pre-to post-training assessment. In contrast, in participants who completed the control task, the CRN, ERN, and.ERN did not differ between the pre- and post-training assessment. The presents study suggests that a single session of attention bias modification reduces neural correlates of response monitoring, including error-related brain activity. These results also support attention bias modification as a potential mechanistic-based intervention for the prevention and treatment of anxiety pathology.
Error processing is impaired in psychosis, and numerous event-related potential studies have found reductions in the error-related negativity (ERN) and, more recently, the error positivity (Pe). The stability of reduced ERN/Pe in psychosis, however, is unknown. In a previous cross-sectional report, reduced ERN was associated with negative symptom severity and reduced Pe with a diagnosis of schizophrenia versus other psychosis. Here, we test the stability of impaired error processing over a four-year follow-up and relationships with subdimensions of negative symptoms. The ERN and Pe were recorded from individuals with psychotic disorders twice: 79 individuals were assessed 15years after first hospitalization, and 69 were assessed at 19years; 59 (26 with schizophrenia, 33 with other psychotic disorders) had data at both assessments. At 19years the Pe was blunted in schizophrenia. The ERN and Pe exhibited temporal stability over the four years (r=0.59 and 0.60, respectively). Reduced ERN and Pe correlated with the negative symptom subdimensions of inexpressivity and avolition, respectively, and not with psychotic or disorganized symptoms. Moreover, 15-year ERN predicted an increase in inexpressivity by year 19. No evidence was found for the reverse: negative symptoms did not predict change in ERN/Pe. Similar to non-clinical samples, the ERN and Pe show impressive four-year stability in late-phase psychosis. The ERN and Pe are promising neural measures for capturing individual differences in psychotic disorders, particularly with regard to negative symptomatology. They may prove to be useful clinically for forecasting illness course and as treatment targets.
Fear conditioning research on threat predictability has primarily examined the impact of temporal (i.e., timing) predictability on the startle reflex. However, there are other key features of threat that can vary in predictability. For example, the reinforcement rate (i.e., frequency) of threat is a crucial factor underlying fear learning. The present study examined the impact of threat reinforcement rate on the startle reflex and self-reported anxiety during a fear conditioning paradigm. Forty-five participants completed a fear learning task in which the conditioned stimulus was reinforced with an electric shock to the forearm on 50% of trials in one block and 75% of trials in a second block, in counter-balanced order. The present study also examined whether intolerance of uncertainty (IU), the tendency to perceive or experience uncertainty as stressful or unpleasant, was associated with the startle reflex during conditions of low (50%) vs. high (75%) reinforcement. Results indicated that, across all participants, startle was greater during the 75% relative to the 50% reinforcement condition. IU was positively correlated with startle potentiation (i.e., increased startle response to the CS+ relative to the CS-) during the 50%, but not the 75%, reinforcement condition. Thus, despite receiving fewer electric shocks during the 50% reinforcement condition, individuals with high IU uniquely demonstrated greater defense system activation when impending threat was more uncertain. The association between IU and startle was independent of state anxiety. The present study adds to a growing literature on threat predictability and aversive responding, and suggests IU is associated with abnormal responding in the context of uncertain threat.
There is growing evidence that unpredictability and uncertainty can alter reward system functioning. The present study examined the impact of (1) a task-irrelevant unpredictable relative to predictable context and (2) individual differences in intolerance of uncertainty (IU) on the reward-related positivity (RewP), an event-related potential (ERP) response to monetary gains relative to losses. Specifically, 64 participants listened to predictable and unpredictable tone sequences while electroencephalography was recorded during a monetary gambling task. Participants also completed the Intolerance of Uncertainty Scale, which measures both cognitive distress (prospective IU) and behavioral inhibition (inhibitory IU) elicited by uncertainty, in addition to the Depression Anxiety Stress Scale-21 and Penn State Worry Questionnaire. Results indicated that the RewP was reduced during the unpredictable relative to the predictable context. Greater self-reported anxiety elicited by the unpredictable context was associated with a decreased RewP, and a decreased RewP was associated with poorer lose-shift behavioral adjustment. Furthermore, the RewP mediated the relationship between self-reported anxiety elicited by the unpredictable context and lose-shift behavioral adjustment. The IU subscales demonstrated the opposite relationship with the RewP across both contexts—inhibitory IU was associated with an attenuated RewP and prospective IU was associated with an enhanced RewP. In contrast, anxiety, depression, stress, and worry symptomatology were not associated with the RewP. This is the first study to demonstrate that an unpredictable context and individual differences in the degree to which people cannot tolerate uncertainty impact an ERP measure of reward system functioning.
An attentional bias to threat has been implicated in the etiology and maintenance of anxiety disorders. Recently, attention bias modification (ABM) has been shown to reduce threat biases and decrease anxiety. However, it is unclear whether ABM modifies neural activity linked to anxiety and risk. The current study examined the relationship between ABM and the error-related negativity (ERN), a putative bio-marker of risk for anxiety disorders, and the relationship between the ERN and ABM-based changes in attention to threat. Fifty-nine participants completed a single-session of ABM and a flanker task to elicit the ERN-in counterbalanced order (i.e., ABM-before vs. ABM-after the ERN was measured). Results indicated that the ERN was smaller (i.e., less negative) among individuals who completed ABM-before relative to those who completed ABM-after. Furthermore, greater attentional disengagement from negative stimuli during ABM was associated with a smaller ERN among ABM-before and ABM-after participants. The present study suggests a direct relationship between the malleability of negative attention bias and the ERN. Explanations are provided for how ABM may contribute to reductions in the ERN. Overall, the present study indicates that a single-session of ABM may be related to a decrease in neural activity linked to anxiety and risk.
Errors are unpredictable events that have the potential to cause harm. The error-related negativity (ERN) is the electrophysiological index of errors and has been posited to reflect sensitivity to threat. Intolerance of uncertainty (IU) is the tendency to perceive uncertain events as threatening. In the present study, 61 participants completed a self-report measure of IU and a flanker task designed to elicit the ERN. Results indicated that IU subscales were associated with the ERN in opposite directions. Cognitive distress in the face of uncertainty (Prospective IU) was associated with a larger ERN and slower reaction time. Inhibition in response to uncertainty (Inhibitory IU) was associated with a smaller ERN and faster reaction time. This study suggests that sensitivity to the uncertainty of errors contributes to the magnitude of the ERN. Furthermore, these findings highlight the importance of considering the heterogeneity of anxiety phenotypes in relation to measures of threat sensitivity.
Like language, semantic memory is productive: It extends itself through self-derivation of new information through logical processes such as analogy, deduction, and induction, for example. Though it is clear these productive processes occur, little is known about the time course over which newly self-derived information becomes incorporated into semantic knowledge. In the present research, we used event-related potentials to examine this dynamic process. Subjects were presented with separate but related facts that, when integrated with one another, supported generation of new information (Integration facts). After 2 400-ms presentations, P600 responses to Integration facts differed from responses to Novel facts and did not differ from responses to Well-known facts, suggesting that the newly self-derived information had been incorporated into the knowledge base. The finding of rapid transition from newly self-derived to well known helps explain the richness of semantic memory. By implication, it also may contribute to the absence of episodic information specifying when and where semantic contents were acquired.
BACKGROUND:Reduced auditory target P300 amplitude is a leading biomarker for psychotic disorders, although its relevance for differential diagnosis and link to specific clinical features (symptom profiles, functional impairment, and course) are unclear. This study aims to clarify the clinical significance of auditory target P300 using concurrent and retrospective clinical data from a longitudinal cohort with psychosis. METHODS:92 cases from an epidemiological study of first-admission psychosis were assessed using an auditory oddball paradigm at 15-year follow-up along with 44 never-psychotic adults. Subcomponents of auditory target P300 amplitude (i.e., a central positive P3a, a parietal positive P3b, and a frontal negative slow wave) were isolated using temporal-spatial principal component analysis. RESULTS:P3a amplitude was blunted across psychotic disorders relative to non-psychotic adults. P3b amplitude was reduced in schizophrenia specifically, including cases initially misclassified at baseline. The frontal negative slow wave did not distinguish among groups. P3b amplitude reduction was associated with several clinical features at the concurrent assessment, as well as previous time points, including recovery from psychosis even 5 years earlier and functioning even 15 years earlier. CONCLUSIONS:Auditory target P300 amplitude yields both a schizophrenia-specific component (i.e., P3b) and a transdiagnostic psychosis component (i.e., P3a). The P3b component may also shed light on prognosis, real-world functioning, and course, as well as help to reduce misdiagnosis of psychotic disorders. Prospective studies are needed to test whether P3b tracks or predicts clinical status.
BACKGROUND:Cognitive impairments and delusions are hallmarks of schizophrenia, and are thought to be due in part to abnormalities in semantic priming. The N400, a neural measure of semantic processing, is found to be reduced in schizophrenia. However, it is unclear if individuals with other psychoses (e.g., mood disorders or substance abuse with psychotic features) also show this impairment, and whether N400 reduction relates to real-world functioning and recovery. METHODS:Eighty-nine individuals from the Suffolk County Mental Health Project, a longitudinal study of first-admission psychosis, and 35 healthy adults were assessed using matched, related, and unrelated picture-word pairs to elicit the N400. Patients' real-world functioning, symptomatology, and recovery were tracked since first hospitalization; EEG assessment was completed during year 15 of the study. RESULTS:Participants with schizophrenia had slower reaction times and reduced N400 to semantically incongruent stimuli relative to healthy participants. Schizophrenia and other psychoses did not differ on N400, suggesting that N400 abnormalities characterize psychosis broadly. When grouped by recovery status, patients who remained ill had a significantly blunted N400, while those who recovered did not differ from healthy adults. Few patients with schizophrenia achieved recovery; therefore recovery results are limited to the other psychosis group. Furthermore, reduced N400 and increased reaction times correlated with greater psychotic symptoms, worse global assessment of functioning scores, unemployment, and impaired social functioning. CONCLUSIONS:Abnormalities in the N400 are not specific to schizophrenia; in addition, the N400 may be a useful neural correlate of recovery and real-world functioning across psychotic disorders.