Accelerometer-based and self-reported physical activity and sedentary time and their relationships with the P300 in a Go/No-Go task in older adults.

Older adults who experience cognitive decline are more likely to have a reduced quality of life. Identifying lifestyle factors that may influence cognitive processing and in turn improve quality of life during older adulthood is an important area of interest. Cognitive function, as measured by the P300 event-related potential (ERP), has been noted to be modified by physical activity; however, no study to date has examined relationships between this neurophysiological measure and physical activity and sedentary time in older adults. Furthermore, there is a gap in understanding as to whether physical activity and sedentary time assessed using self-reported and accelerometer-based methods similarly relate to the P300. This study aimed to assess the P300 during a Go/No-Go task in relation to self-reported and accelerometer-based physical activity and sedentary time in a community sample of 75 older adults. Results indicated that participants engaging in more moderate-to-vigorous physical activity had larger P300 amplitudes across self-reported and accelerometer-based measurements; however, no relationships between sedentary time and P300 amplitude were observed. Notably, accelerometer-based moderate-to-vigorous physical activity explained P300 amplitudes over and above self-reported moderate-to-vigorous physical activity-an effect that remained significant even after accounting for age. Although these results highlight the importance of moderate-to-vigorous physical activity in relation to cognitive function, as measured via the P300 in older adults, a secondary analysis indicated that engaging in lifestyle activity may have similar effects on the P300 as moderate-to-vigorous physical activity. In sum, the present study highlights the role of habitual engagement in physical activity as a possible means for supporting cognitive function during the aging process.

Familial risk for depression is associated with reduced physical activity in young adults: evidence from a wrist-worn actigraphy study.

Depression is characterized by reduced physical activity and sleep-wake cycle disturbances, often considered important features of the disease. While a few studies have suggested that self-reported reduced physical activity and sleep-wake cycle disturbances might both be linked to depression vulnerability, actigraphy-based measures in vulnerable samples remain largely unexplored. This study relied on actigraphy-based parameters to test whether these disturbances characterize depression vulnerability. Seven-day actigraphy data were collected from 20 (13 female) university students with a high vulnerability to depression, which was determined by the presence of a family history of the condition but no current symptoms, and 32 (21 female) controls with neither a family history of depression nor current depressive symptoms. Daily physical activity, namely gross motor activity, was quantified as average daily acceleration and time spent engaging in moderate-vigorous physical activity (MVPA). The sleep-wake cycle and circadian rhythms were assessed as total sleep duration per night (in hours), sleep within sleep period time (in hours), sleep efficiency (%), and relative amplitude (i.e., the difference between the activity during the day and the night, which reflects circadian rhythms amplitude). Results showed that individuals with a familial risk for depression exhibited reduced daily acceleration and time spent in MVPA relative to the control group, particularly on the weekend during their free time away from scheduled activities. On the other hand, the two groups were comparable in terms of sleep estimates. Taken together, reduced physical activity, but not sleep-wake disturbances, seem to be associated with vulnerability to depression and might be a viable target for identification and prevention efforts.

Effort and Appetitive Responding in Depression: Examining Deficits in Motivational and Consummatory Stages of Reward Processing Using the Effort-Doors Task.

Background: Reward sensitivity is a dimensional construct central to understanding the nature of depression. Psychophysiological research on this construct has primarily focused on the reward positivity, an event-related potential (ERP) that indexes consummatory reward sensitivity. This study extended prior research by focusing on ERPs that index the motivational component of reward. Methods: A novel effort-for-reward task was used to elicit motivational and consummatory ERPs. Groups consisting of 34 participants with depression and 32 participants without depression were compared across a range of reward-related ERPs. Results: Participants with depression exhibited reduced responsivity to effort completion cues following high effort expenditure, reduced anticipation of rewards after low effort expenditure (i.e., the stimulus preceding negativity), and reduced reward positivity following high effort expenditure. ERPs occurring prior to reward receipt accounted for unique variance in depression status and differentiated between subgroups of depressed individuals. Conclusions: Findings support the utility of leveraging multiple ERPs that index separate reward processing deficits to better characterize depression and depressive subtypes.

Cumulative lifetime acute stressor exposure interacts with reward responsiveness to predict longitudinal increases in depression severity in adolescence.

BACKGROUND: Life stress and blunted reward processing each have been associated with the onset and maintenance of major depressive disorder. However, much of this work has been cross-sectional, conducted in separate lines of inquiry, and focused on recent life stressor exposure, despite the fact that theories of depression posit that stressors can have cumulative effects over the lifespan. To address these limitations, we investigated whether acute and chronic stressors occurring over the lifespan interacted with blunted reward processing to predict increases in depression over time in healthy youth. METHOD: Participants were 245 adolescent girls aged 8-14 years old (Mage = 12.4, s.d. = 1.8) who were evaluated at baseline and two years later. The reward positivity (RewP), an event-related potential measure of reward responsiveness, was assessed at baseline using the doors task. Cumulative lifetime exposure to acute and chronic stressors was assessed two years later using the Stress and Adversity Inventory for Adolescents (Adolescent STRAIN). Finally, depressive symptoms were assessed at both baseline and follow-up using the Children's Depression Inventory. RESULTS: As hypothesized, greater lifetime acute stressor exposure predicted increases in depressive symptoms over two years, but only for youth exhibiting a blunted RewP. This interaction, however, was not found for chronic stressors. CONCLUSIONS: Lifetime acute stressor exposure may be particularly depressogenic for youth exhibiting a blunted RewP. Conversely, a robust RewP may be protective in the presence of greater acute lifetime stressor exposure.

Influences of age and pubertal development on P300 amplitude trajectory across two years in female adolescents.

The P300 event-related potential (ERP) has been extensively studied across the human lifespan. However, many studies examining age-related effects are cross-sectional, and few have considered the unique role that pubertal development may have on P300 developmental trajectories. The current study examined whether age, pubertal maturation or their interaction predicted changes in P300 amplitude over two years among 129 females between the ages of 8 and 15 years at baseline. Participants completed a flanker task while EEG was recorded at a baseline and two-year follow-up visit. Both baseline age and increased pubertal development were associated with smaller P300 amplitude at follow-up. However, the influence of age was qualified by an interaction between age and pubertal maturation: among younger girls only, increased pubertal development predicted decreases in P300, whereas decreased pubertal development predicted increases in P300. These data indicate that pubertal timing impacts neurodevelopmental changes in P300 amplitude - such that high versus low pubertal development among 8- to 10-year-old girls predicted differential trajectories of neural activity. In light of links between reduced P300 and mental health disorders, such as depression, future studies might examine whether neurodevelopmental changes influenced by early-onset pubertal development could account for increases in these mental health problems.

Error-related brain activity in pediatric major depressive disorder: An ERP and time-frequency investigation.

BACKGROUND: The error-related negativity (ERN) reflects individual differences in error monitoring. However, findings on the ERN in adult and adolescent depression have been inconsistent. Analyzing electroencephalographic (EEG) data in both the time- and time-frequency domain can be useful to better quantify neural response to errors. The present study aimed at examining electrocortical measures of error monitoring in early adolescents with and without depression. METHOD: EEG activity was collected during an arrowhead version of the flanker task in 29 (25 females) early adolescents with depression and 34 without MDD (29 females). RESULTS: The depression group showed reduced ERN amplitude, reduced error-related theta power and increased error-related beta power compared to the control group. When all variables that related to MDD diagnosis were considered simultaneously, both theta and beta power, but not the ERN, were independently related to an increased likelihood of being diagnosed with depression. CONCLUSIONS: By examining both time-domain and separate time-frequency measures, the present study provided novel evidence on error monitoring alterations in youth depression, suggesting that depression during adolescence may be characterized by reduced error monitoring (i.e., reduced ERN and error-related theta) and post-error inhibition (i.e., greater error-related beta power). These results support that time-frequency measures might be better suited for examining error-related neural activity in MDD relative to time-domain measures.

Corporal Punishment Is Uniquely Associated With a Greater Neural Response to Errors and Blunted Neural Response to Rewards in Adolescence.

BACKGROUND: Although corporal punishment is a common form of punishment with known negative impacts on health and behavior, how such punishment affects neurocognitive systems is relatively unknown. METHODS: To address this issue, we examined how corporal punishment affected neural measures of error and reward processing in 149 adolescent boys and girls of ages 11 to 14 years (mean age [SD] = 11.02 [1.16]). Corporal punishment experienced over the lifetime was assessed using the Stress and Adversity Inventory. In addition, participants completed a flankers task and a reward task to measure the error-related negativity and reward positivity, respectively, as well as measures of anxiety and depressive symptoms. RESULTS: As hypothesized, participants who experienced lifetime corporal punishment reported more anxiety and depressive symptoms. Experiencing corporal punishment was also related to a larger error-related negativity and blunted reward positivity. Importantly, corporal punishment was independently related to a larger error-related negativity and a more blunted reward positivity beyond the impact of harsh parenting and lifetime stressors. CONCLUSIONS: Corporal punishment appears to potentiate neural response to errors and decrease neural response to rewards, which could increase risk for anxiety and depressive symptoms.

The P300, loneliness, and depression in older adults.

Depression is associated with high levels of cognitive impairment and increased loneliness among older adults. The current study examines associations between a reliable and robust neural marker of cognitive impairment (i.e., the P300 event-related brain potential [ERP]), loneliness, and depression and assesses the role of loneliness in the P300─depression relationship. In a community sample of 70 older adults between 61 and 75 years, we evaluated cross-sectional associations between depressive symptoms (Geriatric Depression Scale), loneliness (NIH Toolbox), and P300 amplitude measured from the electroencephalogram during a go/no-go task. Results indicated that reduced go and no-go P300 amplitudes were associated with increased depressive symptom severity, with the most unique variance accounted for by a reduced no-go P300 amplitude. Notably, loneliness significantly moderated the no-go P300-depressive symptom severity relationship, such that there was no relationship between the no-go P300 and depressive symptom severity among older adults reporting low levels of loneliness. This finding provides insight into the possibility that social support may offer protection against the depressogenic effects of poor inhibitory control in older adults. Taken together, this study provides a novel examination of the relationships between depression, loneliness, and the P300 ERP in older adults, with important implications for understanding the role of neural inhibition and loneliness in relation to depressive symptomatology.

Emotion regulation and the late positive potential (LPP) in older adults.

Emotion regulation (ER) processes in older adults may be important for successful aging. Neural correlates of ER processes have been examined using event-related brain potentials (ERPs), such as the late-positive potential (LPP) during cognitive reappraisal paradigms. The current study sought to extend this research by examining the LPP from an ER task in a sample of 47 community-dwelling older adults between the ages of 60 and 84 years, scoring either high on emotional well-being (as measured by habitual ER use and resiliency; high WB group, n = 20) or low on emotional well-being (as measured by habitual ER use, resiliency, and depression; low WB group, n = 27). Participants viewed unpleasant and neutral images and were instructed to simply react to the images or reappraise their emotional response. Both pre- and post-instruction LPP amplitudes were scored, in addition to self-reported ratings of negative emotion collected during the task. We found greater LPP amplitude to emotionally salient compared to neutral stimuli, reduced LPP amplitude following instructions to reappraise emotional response to stimuli across groups, and a blunted LPP overall for individuals with higher depressive symptoms. Additionally, we demonstrated that older adults with low emotional well-being were less successful at reappraisal according to self-reported ratings of negative emotion, although this was not reflected in the LPP. Collectively, these data suggest that laboratory-based ER tasks might be used to understand abnormal ER use-though the LPP may be more sensitive to depression than individual differences in ER ability.

Reduced electrocortical responses to pleasant pictures in depression: A brief report on time-domain and time-frequency delta analyses.

BACKGROUND: The late positive potential (LPP) to pleasant content is an electrocortical indicator of blunted emotional reactivity in depression. A reduced time-frequency delta power has never been investigated in clinical samples. The present study examined time-frequency delta in depression and at investigated whether the combination of time-domain and time-frequency data would explain additional variance in the depression status. METHODS: The study was a secondary analysis of data collected during a passive viewing task of pleasant and neutral pictures in a community-based sample of 75 participants with a current depressive disorder and 42 controls. A time-frequency analysis on event-related changes within delta frequency band was conducted. RESULTS: Cluster-based statistics revealed a centro-parietal increase in delta power to pleasant relative to neutral pictures in the control group but not within the depression group. Moreover, a fronto-centro-parietal reduction in delta power to pleasant pictures emerged in depression relative to controls. Both a smaller LPP and delta power to pleasant pictures were related to depression status. The combination of LPP and delta power explained a greater amount of variance compared to the model where LPP was entered as the only predictor of depression status. CONCLUSIONS: These data suggest that delta power might be a promising electrocortical correlate of the hypoactivation of the approach-related motivational system in depression. Additionally, a blunted delta and LPP might reflect unique processes related to depression. A combination of these measures can be leveraged together to enhance clinical utility and to shed light on the underlying mechanisms associated with depression.

Depression reduces neural correlates of reward salience with increasing effort over the course of the progressive ratio task.

BACKGROUND: Depressive disorders have been associated with altered effort-cost decision making (ECDM) in behavioral investigations, such as a decreased willingness to expend effort for reward attainment. However, little is known about neural mechanisms implicated in altered ECDM. METHODS: The study investigates neural correlates of reward attainment during a progressive ratio task in participants with a current depressive disorder (n = 65) and never-depressed healthy individuals (n = 44). On each trial, participants completed an increasing number of button presses to attain a fixed monetary reward, indicated by an auditory reward signal. Participants could decide to quit the task anytime (breakpoint). EEG was recorded during the task and P300 amplitudes were examined in response to the auditory signal of reward attainment. RESULTS: There was no difference in breakpoint, as both groups completed comparable numbers of button presses. In contrast, results from mixed-effects models of trial-level ERP responses indicated depression-related effects on P300 amplitudes over the course of the task. Generally, the reward-locked P300 increased with ascending effort expenditure; however, compared to healthy participants, individuals with current depression were characterized by an attenuated trajectory of the reward-locked P300, pointing towards decreased reactivity to reward attainment with increasing effort. LIMITATIONS: Sample size and reward magnitude were possibly not large enough to detect differences in breakpoint. CONCLUSIONS: The results of the current study demonstrate that the investigation of reward-related P300 trajectory may represent an informative novel addition to the progressive ratio task, which could help shed light on depression-related alterations in motivation and ECDM.

A randomized trial of aerobic exercise for major depression: examining neural indicators of reward and cognitive control as predictors and treatment targets.

BACKGROUND: Aerobic exercise has demonstrated antidepressant efficacy among adults with major depression. There is a poor understanding of the neural mechanisms associated with these effects. Deficits in reward processing and cognitive control may be two candidate targets and predictors of treatment outcome to exercise in depression. METHODS: Sixty-six young adults aged 20.23 years (s.d. = 2.39) with major depression were randomized to 8 weeks of moderate-intensity aerobic exercise (n = 35) or light stretching (n = 31). Depressive symptoms were assessed across the intervention to track symptom reduction. Reward processing [reward positivity (RewP)] and cognitive control [error-related negativity (ERN)] were assessed before and after the intervention using event-related brain potentials. RESULTS: Compared to stretching, aerobic exercise resulted in greater symptom reduction (gs = 0.66). Aerobic exercise had no impact on the RewP (gav = 0.08) or ERN (gav = 0.21). In the aerobic exercise group, individuals with a larger pre-treatment RewP [odds ratio (OR) = 1.45] and increased baseline depressive symptom severity (OR = 1.18) were more likely to respond to an aerobic exercise program. Pre-treatment ERN did not predict response (OR = 0.74). CONCLUSIONS: Aerobic exercise is effective in alleviating depressive symptoms in adults with major depression, particularly for those with increased depressive symptom severity and a larger RewP at baseline. Although aerobic exercise did not modify the RewP or ERN, there is preliminary support for the utility of the RewP in predicting who is most likely to respond to exercise as a treatment for depression.

Appearance concerns are uniquely associated with LPP amplitude to pictures of oneself.

A number of psychiatric disorders, including body dysmorphic disorder (BDD), anorexia nervosa, bulimia nervosa, and social anxiety disorder, are characterized by heightened appearance concerns and increased cognitive and perceptual biases toward one's own physical appearance. In the present study, we examined individual differences in self-reported appearance anxiety and symptoms of BDD in relation to the late positive potential (LPP)-an index of stimulus significance-in response to pictures of oneself, strangers and objects among 83 female college students. The results indicated that the LPP was larger for pictures of oneself compared to pictures of strangers and objects. Further, the Yale-Brown Obsessive-Compulsive Scale Modified for Body Dysmorphic Disorder and Appearance Anxiety Inventory scales both related to an increased LPP to pictures of oneself but not to strangers or objects. The findings suggest that the LPP elicited by pictures of oneself may function as a neural marker of appearance concerns, which could be leveraged to study the development and maintenance of a range of psychiatric disorders characterized by increased appearance concerns.

Maternal suicidality interacts with blunted reward processing to prospectively predict increases in depressive symptoms in 8-to-14-year-old girls.

Both a hypoactive reward system and maternal depression are associated with the onset of Major Depressive Disorder (MDD) in youth. Recent research indicates that blunted reward processing and maternal history of depression may interact to predict increases in depressive symptoms, however, the role of specific maternal depressive symptoms has not been examined. The current study investigated whether maternal depressive symptoms, history of MDD, and suicidal thoughts and/or behaviors (STBs) might lead to prospective increases in depressive symptoms one year later in the context of hypoactive reward processing. In a sample (N = 212) of 8 to 14-year-old girls, we assessed depressive symptoms in youth at baseline and follow up, while reward processing was measured using the Reward Positivity (RewP) event-related brain potential. Maternal STBs, current depressive symptoms, and history of maternal MDD were assessed at baseline. The results indicated that only girls with a blunted RewP and maternal STBs exhibited increased depressive symptoms one year later. These results were not evident when maternal depressive symptoms or maternal history of MDD was examined as the moderator. Overall, the current study provides evidence that maternal STBs uniquely impact youth with blunted reward processing.

Neural responses to reward and pleasant pictures prospectively predict remission from depression.

Reduced neural responses to reward and pleasant stimuli-indicators of anhedonia and reduced emotional reactivity, respectively-have been reported among individuals with depressive disorders. The current study examined whether these neural measures could prospectively predict the course of depression among a community-based sample of 83 participants diagnosed with a depressive disorder. At initial assessment, participants performed both a guessing task to elicit the reward positivity (RewP) and a picture viewing paradigm with neutral and pleasant pictures to measure the late positive potential (LPP)-both event-related brain potentials (ERPs) independently related to diagnosis of depression. After approximately 9 months, 53 of those participants returned to the lab for a clinical assessment of current symptoms and course of disorder during the follow-up period. We found a more intact (i.e., larger) RewP and LPP at baseline among participants who achieved an episode of full remission from depression at any point during the follow-up period. In multiple logistic regression models, the RewP and LPP were both independent predictors of remission status; moreover, the RewP, but not the LPP, remained a significant predictor after accounting for other clinical variables that predicted remission. These data provide initial evidence for the clinical utility of ERPs from reward and picture viewing tasks within depressed individuals to predict disease course prospectively, which could be further leveraged to improve intervention approaches and parse the heterogeneity of depression. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Doors P300 moderates the relationship between reward positivity and current depression status in adults.

BACKGROUND: Previous research has found deficits in both the reward positivity (RewP) and P300 components of the event-related potential (ERP) in relation to depression. The current study examined whether the P300, elicited from imperative stimuli in a gambling task, relates to depression - and can be utilized in tandem with the RewP to better account for individual differences in depression. METHODS: In the current study, 80 adults with current depression (Mage = 39.65, 79% female) and 43 healthy controls (Mage = 37.02, 81% female) completed clinical interviews, self-report questionnaires, and the doors gambling task while EEG was recorded. RESULTS: Results indicated a reduced P300 to doors stimuli (i.e., doors P300) in depression, especially among depressed individuals reporting heightened anhedonia. Gain and loss feedback P300s did not differ between groups. Moreover, the doors P300 moderated the association between RewP and depression status: individuals with relatively intact reward processing (i.e., larger RewP) were more likely to be currently depressed if they exhibited a reduced P300. LIMITATIONS: The majority of the sample identified as Caucasian which reduces generalizability of current results. Additionally, the current study is cross sectional design which limits insight into how these ERPs coincide with changes in the disorder. CONCLUSIONS: The current study demonstrates that a novel P300 component to the doors stimulus appears to be blunted in currently depressed individuals, and that using the doors P300 in combination with the RewP accounts for significantly more variance in depression.

The impact of a single session of aerobic exercise on positive emotional reactivity in depression: Insight into individual differences from the late positive potential.

Depression has been characterized by a broad disengagement from the environment, as reflected by dampened positive and negative emotional reactivity. Research has shown that acute exercise may enhance positive emotional reactivity in healthy adults. It is unknown whether it can alter positive emotional reactivity in depression. In the present study, positive emotional reactivity was assessed using the late positive potential (LPP) event-related potential before and after 30 min of moderate-intensity aerobic exercise in 43 adults with current or a lifetime history of depression (Mage = 32.74 years; Min/Max = 18/59) and 18 never-depressed healthy adults (Mage = 37.94 years; Min/Max = 21/61). Acute exercise increased the LPP for healthy adults; the LPP did not change among those with current or a lifetime history of depression. A secondary aim was to identify moderators of change in positive emotional reactivity among subgroups of adults with current depression. Compared to adults with impaired mood reactivity, those with intact mood reactivity had a pre-to-post increase in the LPP. The current study provides preliminary support for the LPP as a neural indicator of exercise efficacy and highlights individual differences in response to acute exercise in depression.

Ventral striatal activation during reward differs between major depression with and without impaired mood reactivity.

BACKGROUND: Recent efforts to classify subtypes of major depressive disorder marked by different psychophysiological indicators have identified blunted reward-related brain activation in gambling tasks as a characteristic linked specifically to depressed participants with impaired mood reactivity. METHODS: The current study compared individuals diagnosed with current depressive disorder (n = 26) with healthy controls (n = 24) regarding brain responses to gain and loss trials in an fMRI version of the "Doors" choice-feedback task. Study aims were to examine reward-related brain activation in relation to depression, depressive subtypes, and course of depression. RESULTS: Across the sample, participants showed a significant response to gain versus loss in left and right ventral striatum as well as medial and left lateral prefrontal cortex. Relative to controls, participants with current depression were characterized by blunted reactivity in left ventral striatum. Furthermore, activation in the left ventral striatum differentiated subgroups of depression with and without impaired mood reactivity. Finally, left striatal hypoactivation to reward predicted remission when controlling for current depressive symptomatology, albeit at a trend level. CONCLUSIONS: Blunted reward-related activation in the left ventral striatum might be useful as a marker for depression subtype and may have the potential to predict future course of depression.

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.

A reduced P300 prospectively predicts increased depressive severity in adults with clinical depression.

Neurocognitive impairments commonly observed in depressive disorders are thought to be reflected in reduced P300 amplitudes. To date, depression-related P300 amplitude reduction has mostly been demonstrated cross-sectionally, while its clinical implication for the course of depression remains largely unclear. Moreover, the relationship between P300 and specific clinical characteristics of depression is uncertain. To shed light on the functional significance of the P300 in depression, we examined whether initial P300 amplitude prospectively predicted changes in depressive symptoms among a community sample of 58 adults (mean age = 38.86 years old, 81% female) with a current depressive disorder. This sample was assessed at two-time points, separated by approximately nine months (range = 6.6-15.9). At the initial visit, participants completed clinical interviews, self-report measures, and a flanker task, while EEG was recorded to derive P300 amplitude. At the follow-up visit, participants again completed the same clinical interviews and self-report measures. Results indicated that a reduced P300 amplitude at the initial visit was associated with higher total depressive symptoms at follow-up, even after controlling for initial depressive symptoms. These data indicate the potential clinical utility for the P300 as a neural marker of disease course among adults with a current depressive disorder. Future research may target P300 in interventions to determine whether depression-related outcomes can be improved.