Shifts in attentional scope modulate event-related potentials evoked by reward.

Emotions broaden or narrow the scope of attention in order to facilitate adaptive responses in threatening and rewarding contexts. In the current study, rather than asking how emotions influence attentional scope, we considered the possibility that the relationship between attentional breadth and emotion is bidirectional by asking whether shifts in attentional scope alter emotional processes using an event-related potential (ERP) paradigm. Participants (N = 30) completed a modified version of a Monetary Incentive Delay (MID) task, wherein their attention was either narrowed or broadened as they attempted to win rewards. Behaviorally, narrowing attention improved task performance in the form of reduced errors and increased monetary winnings. During cue processing, narrowing (compared to broadening) attention reduced the Cue-P3 (irrespective of cue type). During feedback processing, narrowing (compared to broadening) attention reduced the Feedback-P3 to monetary wins and increased the Feedback-P2 and the Feedback-P3 to monetary non-wins. Results highlight complexity and bidirectionality in the relationship between attentional scope and affective processes.

Emotional content impacts how executive function ability relates to willingness to wait and to work for reward.

Research has demonstrated that better value-based decision making (e.g., waiting or working for rewards) relates to greater executive function (EF) ability. However, EF is not a static ability, but is influenced by the emotional content of the task. As such, EF ability in emotional contexts may have unique associations with value-based decision making, in which costs and benefits are explicit. Participants (N = 229) completed an EF task (with both negative and neutral task conditions) and two value-based decision-making tasks. Willingness to wait and to work were evaluated in separate path models relating the waiting and working conditions to the EF conditions. Willingness to wait and willingness to work showed distinct relationships with EF ability: Greater EF ability on a negative, but not on a neutral, EF task was related to a willingness to wait for a reward, whereas greater EF ability across both EF tasks was related to a greater willingness to work for a reward. EF ability on a negative EF task showed an inverted-U relationship to willingness to wait for reward, and was most related to willingness to wait at a 6-month delay. Greater EF, regardless of whether the task was negative or neutral, was related to a greater willingness to work when reward was uncertain (50%) or was likely (88%), but not when reward was unlikely (12%). This study suggests that the emotional content of value-based decisions impacts the relationship between EF ability and willingness to wait or to work for reward.

Lack of effect of methamphetamine on reward-related brain activity in healthy adults.

INTRODUCTION: Stimulant drugs are thought to alter processing of rewarding stimuli. However, the mechanisms by which they do this are not fully understood. METHOD: In this study we used EEG to assess effects of single doses of methamphetamine (MA) on neural responses during anticipation and receipt of reward in healthy volunteers. Healthy young men and women (N = 28) completed three sessions in which they received placebo, a low MA dose (10 mg) or a higher MA dose (20 mg) under double blind conditions. Subjective and cardiovascular measures were obtained, and EEG was used to assess brain activity during an electrophysiological version of the Monetary Incentive Delay (eMID) task. RESULTS: EEG measures showed expected patterns during anticipation and receipt of reward, and MA produced its expected effects on mood and cardiovascular function. However, MA did not affect EEG responses during either anticipation or receipt of rewards. CONCLUSIONS: These findings suggest that the effects of MA on EEG signals of reward processing are subtle, and not related to the drug's effects on subjective feelings of well-being. The findings contribute to our understanding of the neural effects of MA during behaviors related to reward.

Severe sexual abuse in childhood and altered neurophysiological response to reward in female adults.

BACKGROUND: A relatively understudied but growing body of research indicates that individuals with a history of childhood trauma exhibit altered reward processing in adulthood. Research to date has focused on adversity broadly, with studies typically finding evidence of blunted response to rewards in adults with a history of childhood trauma. OBJECTIVE: Given the role of reward processing in risk for psychopathology and the particularly pathogenic nature of sexual abuse (SA), the present study sought to assess whether adults with a history of severe childhood SA exhibit altered neurophysiological response to rewards. PARTICIPANTS AND SETTING: Female adults (N = 105) were included from two study sites that used the same measures of childhood trauma (Childhood Trauma Questionnaire, CTQ), reward processing (Doors Task), and psychopathology (SCID). METHODS: Based on participants' CTQ and SCID responses, three groups were created: Severe SA (n = 36), Clinical Match (with comparable lifetime psychopathology but no-to-minimal SA history; n = 35), and Healthy Controls (n = 34). Group differences in RewP amplitude were assessed. RESULTS: The Severe SA group exhibited larger reward positivity (RewP) amplitude to monetary rewards than the Clinical Match and Healthy Control groups (partial ƞ2 = 0.06, p = .047). This effect remained after covarying for severity of other forms of childhood trauma. CONCLUSIONS: Our study found that severe SA in childhood was related to a heightened response to reward in adulthood. Furthermore, this was not attributable to the severity of other forms of early trauma or comorbid psychopathology. Future studies are needed to identify how heightened reward processing following severe childhood SA may be implicated in the onset and course of psychopathology.

Electrophysiological evidence of mal-adaptation to error in remitted depression.

Identifying risk markers for major depressive disorder (MDD) that persist into remission is key to address MDD's high rate of recurrence. Central to MDD recurrence are the disorder's negative information processing biases, such as heightened responses to errors, which may subsequently impair abilities to monitor performance and adjust behaviors based on environmental demands. However, little is known regarding the neurophysiological correlates of post-error adaptation in depression. The current study investigated event-related potentials (ERPs) and behavioral performance following errors from a flanker task in 58 participants with remitted MDD (rMDD) and 118 healthy controls (HC). Specifically, using trial-level data, we tested: (a) the impact of errors on response-locked ERPs of the current and post-error trials (error-related negativity [ERN] and correct response negativity [CRN]) and (b) longer-term adaptation to errors (ERN/CRN) over the course of the task. Compared to HC, rMDD participants showed a larger ERN to the current trial and smaller habituation in ERN over time. On trials immediately following errors, rMDD participants showed slower reaction times that were predicted by the previous-trial ERN amplitude but comparable accuracy to HC, suggesting a deficient ability to disengage from errors and/or a compensatory effort to mitigate accuracy decrements. Critically, this pattern of responding: (a) was concurrently associated with greater levels of anhedonia symptoms, more severe MDD history, and interpersonal impairment (but lower impairment in life activities) and (b) predicted more anhedonia symptoms at one-year follow-up. Collectively, a hyperactive performance monitoring system may be a useful risk marker for future MDD recurrence.

Δ9-THC reduces reward-related brain activity in healthy adults.

RATIONALE: Greater availability of cannabis in the USA has raised concerns about adverse effects of the drug, including possible amotivational states. Lack of motivation may be assessed by examining acute effects of cannabinoids on reward processing. OBJECTIVES: This study examined single doses of delta-9-tetrahydrocannabinol (∆9-THC; 7.5, 15 mg oral) in healthy adults using a version of the monetary incentive delay (MID) task adapted for electroencephalography (EEG; e-MID) in a within-subjects, double blind design. METHODS: Two phases of reward processing were examined: anticipation, which occurs with presentation of cues that indicate upcoming reward, punishment, or neutral conditions, and outcome, which occurs with feedback indicating hits or misses. During anticipation, we measured two event-related potential (ERP) components: the P300, which measures attention and motivation, and the LPP, which measures affective processing. During outcome processing, we measured P300 and LPP, as well as the RewP, which measures outcome evaluation. RESULTS: We found that ∆9-THC modulated outcome processing, but not reward anticipation. Specifically, both doses of ∆9-THC (7.5 and 15 mg) reduced RewP amplitudes after outcome feedback (hits and misses) relative to placebo. ∆9-THC (15 mg) also reduced P300 and LPP amplitudes following hits compared to misses, relative to both placebo and 7.5 mg ∆9-THC. CONCLUSIONS: These findings suggest that ∆9-THC dampens responses to both reward and loss feedback, which may reflect an "amotivational" state. Future studies are needed to determine generalizability of this effect, such as its pharmacological specificity and its specificity to monetary vs other types of reward.

Reappraisal and suppression emotion-regulation tendencies differentially predict reward-responsivity and psychological well-being.

Individuals who suppress their emotions experience less positive emotions, worse relationships, and a reduced quality of life whereas those who tend to reappraise show an opposite pattern. Despite this divergent pattern, few have asked how the use of these emotion-regulation strategies relates to reward responsivity. We predicted that elevated suppression would be associated with blunted reward responsivity, whereas reappraisal would be associated with elevated reward responsivity. To test this hypothesis, participants completed a measure of individual differences in emotion-regulation strategies, measures of self-reported reward responsivity, and then a reward time-estimation task (Kotani et al., 2003) while electroencephalography (EEG) was recorded. Results revealed that individual differences in cognitive reappraisal were unrelated to self-report measures of reward responsivity, whereas suppression was associated with blunted reward responsivity. At the neural level, reappraisal was associated with greater attention to the rewarding cues, as indexed by the P300 event-related potential (ERP) component, whereas suppression was related to blunted reward anticipation, as indexed by the stimulus-preceding negativity (SPN) ERP component. Suppression prospectively predicted worse psychological well-being 2.5 years later and blunted neural reward anticipation partially explained this association. Taken together with past research, these results suggest reappraisal tendencies may lead to better outcomes due, in part, to enhanced reward responsivity, whereas the negative consequences of suppression may be associated with blunted reward responsivity.

Hypomania and depression associated with distinct neural activity for immediate and future rewards.

Bipolar spectrum and unipolar depressive disorders have been associated with distinct and opposite profiles of reward-related neural activity. These opposite profiles may reflect a differential preexisting vulnerability for both types of disorders. In support, recent ERP studies find that, following reward feedback, a larger reward positivity (RewP) is associated with greater vulnerability for bipolar spectrum disorders, whereas a smaller RewP is associated with greater vulnerability for depression. However, prior studies have investigated only immediate rewards and have not examined dimensions of both bipolar disorder and unipolar depression within the same sample. The present study is the first to investigate feedback-related ERP correlates of proneness to hypomania and unipolar depressive tendencies within the same sample and to expand our scope to include future rewards. Participants completed a modified time estimation task where the same monetary reward was available immediately or at one of five different future dates. Results revealed proneness to hypomania and unipolar depressive tendencies were related to an elevated and blunted RewP, respectively, but only following immediate rewards (i.e., today). Following rewards in the distant future (e.g., 8 months), proneness to hypomania and depressive tendencies were associated with elevated and blunted amplitudes for the P3, respectively, a subsequent ERP component reflecting motivational salience during extended feedback processing. Furthermore, these opposing profiles were independent of, and significantly different from, one another. These results suggest that feedback-related ERPs following immediate and future rewards are candidate biomarkers that can physiologically separate vulnerability for bipolar spectrum from unipolar depressive disorders.

Beyond the FRN: Broadening the time-course of EEG and ERP components implicated in reward processing.

Most reward-related electroencephalogram (EEG) studies focus exclusively on the feedback-related negativity (FRN, also known as feedback negativity or FN, medial-frontal negativity or MFN, feedback error-related negativity or fERN, and reward positivity or RewP). This component is usually measured approximately 200-300 ms post-feedback at a single electrode in the frontal-central area (e.g., Fz or FCz). The present review argues that this singular focus on the FRN fails to leverage EEG's greatest strength, its temporal resolution, by underutilizing the rich variety of event-related potential (ERP) and EEG time-frequency components encompassing the wider temporal heterogeneity of reward processing. The primary objective of this review is to provide a comprehensive understanding of often overlooked ERP and EEG correlates beyond the FRN in the context of reward processing with the secondary goal of guiding future research toward multistage experimental designs and multicomponent analyses that leverage the temporal power of EEG. We comprehensively review reward-related ERPs (including the FRN, readiness potential or RP, stimulus-preceding negativity or SPN, contingent-negative variation or CNV, cue-related N2 and P3, Feedback-P3, and late-positive potential or LPP/slow-wave), and reward-related EEG time-frequency components (changes in power at alpha, beta, theta, and delta bands). These electrophysiological signatures display distinct time-courses, scalp topographies, and reflect independent psychological processes during anticipatory and/or outcome stages of reward processing. Special consideration is given to the time-course of each component and factors that significantly contribute to component variation. Concluding remarks identify current limitations along with recommendations for potential important future directions.

Suppression of error-preceding brain activity explains exaggerated error monitoring in females with worry.

Anxiety is consistently associated with hyperactive neural responses to errors. The majority of existing research has focused on a single marker of error-elicited brain activity-the error-related negativity (ERN), an event-related brain potential (ERP) elicited 50-100ms following an erroneous response. The ERN has accumulated growing interest for its use in clinical contexts as a potential biomarker and/or endophenotype. However, it is unknown whether anxiety's effects are specific to brain activity following erroneous responses; anxiety may affect processes prior to error commission, suggesting that the ERN might reflect the output of abnormal processing that begins before an error. Here, we examined the error-preceding positivity (EPP) - an ERP time-locked to the correct response immediately before errors - that reflects a gradual disengagement of task-focused attention preceding errors. Results revealed that female worriers demonstrated significantly attenuated EPP amplitude, indicating reduced pre-error disengagement. Moreover, reduced EPP mediated the relationship between worry and the enhanced ERN following errors. These results suggest that the temporal dynamics of anxiety's impact on error processing are more nuanced than previously thought such that effects emerge prior to the actual occurrence of an erroneous response.