An EEG-Based Neuroplastic Approach to Predictive Coding in People With Schizophrenia or Traumatic Brain Injury.

Despite different etiologies, people with schizophrenia (SCZ) or with traumatic brain injury (TBI) both show aberrant neuroplasticity. One neuroplastic mechanism that may be affected is prediction error coding. We used a roving mismatch negativity (rMMN) paradigm which uses different lengths of standard tone trains and is optimized to assess predictive coding. Twenty-five SCZ, 22 TBI (mild to moderate), and 25 healthy controls were assessed. We used a frequency-deviant rMMN in which the number of standards preceding the deviant was either 2, 6, or 36. We evaluated repetition positivity to the standard tone immediately preceding a deviant tone (repetition positivity [RP], to assess formation of the memory trace), deviant negativity to the deviant stimulus (deviant negativity [DN], which reflects signaling of a prediction error), and the difference wave between the 2 (the MMN). We found that SCZ showed reduced DN and MMN compared with healthy controls and with people with mild to moderate TBI. We did not detect impairments in any index (RP, DN, or MMN) in people with TBI compared to controls. Our findings suggest that prediction error coding assessed with rMMN is aberrant in SCZ but intact in TBI, though there is a suggestion that severity of head injury results in poorer prediction error coding.

Sustained mental health and functional responses to the COVID-19 pandemic in Black and White Veterans with psychosis or recent homelessness.

The COVID-19 pandemic disproportionately impacted marginalized populations including Black Americans, people with serious mental illness, and individuals experiencing homelessness. Although the double disadvantage hypothesis would suggest that individuals with multiple minoritized statuses would experience worse psychosocial impacts from the pandemic, this may not be the case for vulnerable Black Veterans. The present study investigated the sustained mental health and functional responses to the pandemic in Black and White Veterans with psychosis or recent homelessness and in a control group of Veterans enrolled in the Department of Veterans Affairs healthcare services. Clinical interviews and questionnaires were administered remotely by telephone at five time points from May 2020 through July 2021, including a retrospective time point for March 2020 (i.e., before the pandemic started). Overall, there was a striking absence of systematic differences by race in the trajectories of psychiatric symptoms and functioning among Veterans during the study period. These findings are consistent with a report on initial responses to the pandemic that revealed only a few select differences by race among Veteran groups. The lack of racial disparities is inconsistent with the double disadvantage hypothesis. Although further investigation is needed, one possible interpretation is that the wrap-around services offered by the Veterans Health Administration may have mitigated expected differences by race among Veterans with psychosis or homelessness. Future research should continue to examine whether VA services mitigate disparities in mental health and psychosocial outcomes.

An ERP Study of Face Processing in Schizophrenia, Bipolar Disorder, and Socially Isolated Individuals from the Community.

People with schizophrenia (SCZ) and bipolar disorder (BD) have impairments in processing social information, including faces. The neural correlates of face processing are widely studied with the N170 ERP component. However, it is unclear whether N170 deficits reflect neural abnormalities associated with these clinical conditions or differences in social environments. The goal of this study was to determine whether N170 deficits would still be present in SCZ and BD when compared with socially isolated community members. Participants included 66 people with SCZ, 37 with BD, and 125 community members (76 "Community-Isolated"; 49 "Community-Connected"). Electroencephalography was recorded during a face processing task in which participants identified the gender of a face, the emotion of a face (angry, happy, neutral), or the number of stories in a building. We examined group differences in the N170 face effect (greater amplitudes for faces vs buildings) and the N170 emotion effect (greater amplitudes for emotional vs neutral expressions). Groups significantly differed in levels of social isolation (Community-Isolated > SCZ > BD = Community-Connected). SCZ participants had significantly reduced N170 amplitudes to faces compared with both community groups, which did not differ from each other. The BD group was intermediate and did not differ from any group. There were no significant group differences in the processing of specific emotional facial expressions. The N170 is abnormal in SCZ even when compared to socially isolated community members. Hence, the N170 seems to reflect a social processing impairment in SCZ that is separate from level of social isolation.

Social cognition and social motivation in schizophrenia and bipolar disorder: are impairments linked to the disorder or to being socially isolated?

BACKGROUND: People with schizophrenia on average are more socially isolated, lonelier, have more social cognitive impairment, and are less socially motivated than healthy individuals. People with bipolar disorder also have social isolation, though typically less than that seen in schizophrenia. We aimed to disentangle whether the social cognitive and social motivation impairments observed in schizophrenia are a specific feature of the clinical condition v. social isolation generally. METHODS: We compared four groups (clinically stable patients with schizophrenia or bipolar disorder, individuals drawn from the community with self-described social isolation, and a socially connected community control group) on loneliness, social cognition, and approach and avoidance social motivation. RESULTS: Individuals with schizophrenia (n = 72) showed intermediate levels of social isolation, loneliness, and social approach motivation between the isolated (n = 96) and connected control (n = 55) groups. However, they showed significant deficits in social cognition compared to both community groups. Individuals with bipolar disorder (n = 48) were intermediate between isolated and control groups for loneliness and social approach. They did not show deficits on social cognition tasks. Both clinical groups had higher social avoidance than both community groups. CONCLUSIONS: The results suggest that social cognitive deficits in schizophrenia, and high social avoidance motivation in both schizophrenia and bipolar disorder, are distinct features of the clinical conditions and not byproducts of social isolation. In contrast, differences between clinical and control groups on levels of loneliness and social approach motivation were congruent with the groups' degree of social isolation.

Neurophysiological indices of face processing in people with psychosis and their siblings: An event-related potential study.

People with schizophrenia experience difficulties with social interactions. One contributor to these social deficits is dysfunction in processing facial features and facial emotional expressions. However, it is not known whether face processing deficits are evident in those with other psychotic disorders or in those genetically at-risk for psychosis (i.e., first-degree relatives of those with psychosis). We assessed event-related potentials (ERPs) during a facial and emotion processing task in 100 people with a diagnosis of schizophrenia or another psychotic condition (PSY), 32 of their siblings (SIB) and 45 healthy comparison participants (CTL). In separate blocks, participants identified the sex (male or female) or emotion (happy, angry, neutral) of faces. In a comparison condition, participants indicated whether buildings had one or two floors. ERPs were examined in two stages. First, we compared ERPs across the emotion, sex and building identification conditions. Second, we compared ERPs among the three different facial emotions. PSY exhibited significantly lower amplitudes over parietal-occipital regions between 111 and 151 ms when viewing faces but not buildings than CTL, consistent with a face-selective N170 ERP component deficit. The SIB group was intermediate for faces, but not significantly different than PSY or CTL. During emotion identification, all three groups showed increased N170 amplitudes to angry and happy versus neutral expressions, with no group differences. In follow up analyses, we examined differences between PSY with or without affective psychosis, and differences between those with schizophrenia versus other psychotic disorders; there were no significant differences in these analyses. Face processing deficits assessed with ERPs were observed in a group of diverse psychotic disorders, though deficits were not seen to be modulated by facial emotion expression. Additionally, N170 deficits are not evident in siblings of those with PSY.

The impact of psychological strengths on Veteran populations' mental health trajectories during the COVID-19 pandemic.

PURPOSE: Mental health trajectories during the COVID-19 pandemic have been examined in Veterans with tenuous social connections, i.e., those with recent homelessness (RHV) or a psychotic disorder (PSY), and in control Veterans (CTL). We test potential moderating effects on these trajectories by psychological factors that may help individuals weather the socio-emotional challenges associated with the pandemic (i.e., 'psychological strengths'). METHODS: We assessed 81 PSY, 76 RHV, and 74 CTL over 5 periods between 05/2020 and 07/2021. Mental health outcomes (i.e., symptoms of depression, anxiety, contamination concerns, loneliness) were assessed at each period, and psychological strengths (i.e., a composite score based on tolerance of uncertainty, performance beliefs, coping style, resilience, perceived stress) were assessed at the initial assessment. Generalized models tested fixed and time-varying effects of a composite psychological strengths score on clinical trajectories across samples and within each group. RESULTS: Psychological strengths had a significant effect on trajectories for each outcome (ps < 0.05), serving to ameliorate changes in mental health symptoms. The timing of this effect varied across outcomes, with early effects for depression and anxiety, later effects for loneliness, and sustained effects for contamination concerns. A significant time-varying effect of psychological strengths on depressive symptoms was evident in RHV and CTL, anxious symptoms in RHV, contamination concerns in PSY and CTL, and loneliness in CTL (ps < 0.05). CONCLUSION: Across vulnerable and non-vulnerable Veterans, presence of psychological strengths buffered against exacerbations in clinical symptoms. The timing of the effect varied across outcomes and by group.

Effort-based decision-making as a determinant of supported employment outcomes in psychotic disorders.

Schizophrenia is associated with a heavy economic burden in the United States that is partly due to the high rates of chronic unemployment. Individual Placement and Support (IPS) is an evidenced-based type of supported employment that can improve job obtainment and work outcomes in psychotic disorders. Outcomes vary widely and a persistent challenge for IPS is low levels of engagement in the initial job search phase. Past studies have focused on interview-based motivation deficits as a key determinant of poor treatment engagement and work outcomes in schizophrenia. New validated performance-based measures of motivation, including effort-based decision-making (EBDM) tasks, may explain supported employment outcomes and provide insights into individual differences in IPS outcomes. This study investigated the degree to which IPS engagement (i.e., number of sessions attended during the first four months of service delivery) was related to baseline interview-based motivation deficits and performance on three EBDM tasks - two tasks of physical effort and one of cognitive effort (i.e., Balloon Task, Effort Expenditure for Rewards Task, Deck Choice Effort Task) - in a sample (N = 47) of people with a psychotic disorder. Results indicated that the level of EBDM performance, specifically on the Balloon Task, predicted IPS engagement, accounting for an additional 17 % of the variance above and beyond interview-based motivation deficits (total R2 = 24 %). Overall, these findings suggest that addressing motivational deficits in effort-based decision-making may be beneficial to IPS engagement, which in turn may improve the trajectory of work outcomes.

Financial health and psychiatric symptoms among veterans with psychosis or recent homelessness during the COVID-19 pandemic.

The COVID-19 pandemic disproportionately impacted the physical health of some vulnerable groups, but further study is needed to investigate the pandemic's impact on financial health and mental well-being. We analyzed data from 158 participants, consisting of 59 veterans with a psychotic disorder (PSY), 49 recently housed veterans (RHV), and a control group of 50 veterans (CTL) who were assessed five times from May 2020-July 2021. This study compared the financial health of these three groups and examined the relation between financial health and psychiatric symptoms. Although the CTL group reported significantly higher income and savings than the PSY and RHV groups, the CTL group reported greater negative financial shocks than the PSY group. The RHV group reported greater material hardship but greater propensity to plan for finances and less financial shocks than the PSY group. Across all three groups, there was a reduction in financial shocks over time and no group showed more change than another. Across time, material hardship, financial shocks, and propensity to plan for finances were each significantly associated with symptoms of major depression. Together, these findings suggest the COVID-19 pandemic did not greatly impact the financial health of PSY and RHV groups possibly because of their limited income and resilience to adversity. Financial health was related to mental health supporting the U.S. government's strategic plan to include financial empowerment services in efforts to improve mental health and reduce veteran suicide. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Neuroimaging of social motivation during winning and losing: Associations with social anhedonia across the psychosis spectrum.

BACKGROUND: Individuals with psychosis spectrum disorders (PSD) have difficulty developing social relationships. This difficulty may reflect reduced response to social feedback involving functional alterations in brain regions that support the social motivation system: ventral striatum, orbital frontal cortex, insula, dorsal anterior cingulate cortex, and amygdala. Whether these alterations span PSD is unknown. METHODS: 71 individuals with PSD, 27 unaffected siblings, and 37 control participants completed a team-based fMRI task. After each trial, participants received performance feedback paired with the expressive face of a teammate or opponent. A 2 × 2 (win versus loss outcome x teammate versus opponent) repeated measures ANOVA by group was performed on activation in the five key regions of interest during receipt of feedback. RESULTS: Across groups, three social motivation regions, ventral striatum, orbital frontal cortex, and amygdala, showed sensitivity to feedback (significant main effect of outcome), with greater activation during win versus loss trials, regardless of whether the feedback was from a teammate or opponent. In PSD, ventral striatum and orbital frontal cortex activation to win feedback was negatively correlated with social anhedonia scores. CONCLUSIONS: Patterns of neural activation during social feedback were similar in PSD, their unaffected siblings, and healthy controls. Across the psychosis spectrum, activity in key social motivation regions during social feedback was associated with individual differences in social anhedonia.

Unconditional Cash Transfers and Association With Clinical Outcomes Among U.S. Veterans With Psychosis or Recent Homelessness.

OBJECTIVE: Three rounds of stimulus checks were distributed to middle- and low-income U.S. adults during the COVID-19 pandemic. This 15-month longitudinal study examined rates of receipt of these stimulus checks, planned expenses, and associations with clinical outcomes among three veteran groups. METHODS: In total, 158 veterans, consisting of 59 with a psychotic disorder, 49 recently homeless veterans, and a comparison group of 50 veterans without a history of psychosis or homelessness, were assessed five times between May 2020 and July 2021. Bivariate analyses were used to compare receipt of stimulus checks and planned expenses among the groups, and multivariable analyses examined how receipt of checks was related to mental health and substance use over time. RESULTS: No group difference was found in receipt of stimulus checks, and 74%-84% of veterans reported receipt of more than one check. Most participants reported plans to use their stimulus checks to pay for bills, groceries, credit card debt, and rent or mortgage or to save the money. Over time, participants who received a greater number of stimulus checks reported significantly decreased symptoms of depression (B=-0.48) and anxiety (B=-0.84) and improved social functioning (B=0.24). For the recently homeless group, a greater number of stimulus checks received was associated with decreases in days of alcohol intoxication and drug use, but the reverse was found for the psychosis group. CONCLUSIONS: Multiple short-term unconditional government cash transfers may improve mental and social functioning among vulnerable populations during major crises, a finding that contributes to the research literature and has policy implications for pandemic and emergency preparedness.

Aberrant reward processing to positive versus negative outcomes across psychotic disorders.

Several studies of reward processing in schizophrenia have shown reduced sensitivity to positive, but not negative, outcomes although inconsistencies have been reported. In addition, few studies have investigated whether patients show a relative deficit to social versus nonsocial rewards, whether deficits occur across the spectrum of psychosis, or whether deficits relate to negative symptoms and functioning. This study examined probabilistic implicit learning via two visually distinctive slot machines for social and nonsocial rewards in 101 outpatients with diverse psychotic disorders and 48 community controls. The task consisted of two trial types: positive (optimal to choose a positive vs. neutral machine) and negative (optimal to choose a neutral vs. negative machine), with two reward conditions: social (faces) and nonsocial (money) reward conditions. A significant group X trial type interaction indicated that controls performed better on positive than negative trials, whereas patients showed the opposite pattern of better performance on negative than positive trials. In addition, both groups performed better for social than nonsocial stimuli, despite lower overall task performance in patients. Within patients, worse performance on negative trials showed significant, small-to-moderate correlations with motivation and pleasure-related negative symptoms and social functioning. The current findings suggest reward processing disturbances, particularly decreased sensitivity to positive outcomes, extend beyond schizophrenia to a broader spectrum of psychotic disorders and relate to important clinical outcomes.

The flickering spotlight of visual attention: Characterizing abnormal object-based attention in schizophrenia.

Schizophrenia is associated with deficits in both object perception and visual attention. However, few studies in schizophrenia have investigated object-based attention, which is dissociable from other forms of visuospatial attention. Recent research in healthy populations has shown that the 'spotlight' of sustained visual attention flickers in a rhythmic, oscillatory fashion at specific frequencies in the 4-12 Hz range. In healthy samples, this oscillatory signature has been used to investigate spatiotemporal dynamics of object-based attention, showing that the attentional spotlight spreads to uncued locations within cued objects, and also periodically alternates focus between cued and uncued objects. In this study, we adapted a performance-based visual object cueing task to investigate object-based attention in individuals with a schizophrenia diagnosis and healthy controls. In controls, spatiotemporal patterns of object-based attention closely resembled those reported in previous studies of healthy individuals. In the schizophrenia group, the oscillatory signature of attention also appeared in the location of the cue and on uncued objects, similar to the effects in controls. Indeed, the oscillatory signature of attention at the spatial location of the cue was stronger in the schizophrenia group than in controls. However, attention did not spread across the cued object in schizophrenia; rather, attention appeared to remain hyperfocused at the spatial location of the cue. These findings provide the first evidence that visual attention has oscillatory characteristics in schizophrenia, as in the general population. The results also show that the fundamental process of attentional spreading which underlies object-based attention is abnormal in schizophrenia.

The impact of the COVID-19 pandemic on mental health and functional outcomes in Veterans with psychosis or recent homelessness: A 15-month longitudinal study.

BACKGROUND: The COVID-19 pandemic has had unprecedented effects on mental health and community functioning. Negative effects related to disruption of individuals' social connections may have been more severe for those who had tenuous social connections prior to the pandemic. Veterans who have recently experienced homelessness (RHV) or have a psychotic disorder (PSY) are considered particularly vulnerable because many had poor social connections prior to the pandemic. METHODS: We conducted a 15-month longitudinal study between May 2020 -July 2021 assessing clinical (e.g., depression, anxiety) and community (e.g., social functioning, work functioning) outcomes. Eighty-one PSY, 76 RHV, and 74 Veteran controls (CTL) were interviewed over 5 assessment periods. We assessed changes in mental health and community functioning trajectories relative to pre-pandemic retrospective ratings and examined group differences in these trajectories. RESULTS: All groups had significantly increased symptoms of depression, anxiety, and concerns with contamination at the onset of the pandemic. However, RHV and PSY showed faster returns to their baseline levels compared to CTL, who took nearly 15 months to return to baseline. With regards to functioning, both RHV and PSY, but not CTL, had significant improvements in family and social networks over time. Work functioning worsened over time only in PSY, and independent living increased over time in both RHV and PSY but not CTL. CONCLUSIONS: These results reveal that vulnerable Veterans with access to VA mental health and case management services exhibited lower negative impacts of the COVID-19 pandemic on mental health and community functioning than expected.

Intact differentiation of responses to socially-relevant emotional stimuli across psychotic disorders: An event-related potential (ERP) study.

Event-related potential (ERP) studies of motivated attention in schizophrenia typically show intact sensitivity to affective vs. non-affective images depicting diverse types of content. However, it is not known whether this ERP pattern: 1) extends to images that solely depict social content, (2) applies across a broad sample with diverse psychotic disorders, and (3) relates to self-reported trait social anhedonia. We examined late positive potential (LPP) amplitudes to images involving people that were normatively pleasant (affiliative), unpleasant (threatening), or neutral in 97 stable outpatients with various psychotic disorders and 38 healthy controls. Both groups showed enhanced LPP to pleasant and unpleasant vs. neutral images to a similar degree, despite lower overall LPP in patients. Within the patients, there were no significant LPP differences among subgroups (schizophrenia vs. other psychotic disorders; affective vs. non-affective psychosis) for the valence effect (pleasant/unpleasant vs. neutral). Higher social anhedonia showed a small, significant relation to lower LPP to pleasant images across all groups. These findings suggest intact motivated attention to social images extends across psychotic disorder subgroups. Dimensional transdiagnostic analyses revealed a modest association between self-reported trait social anhedonia and an LPP index of neural sensitivity to pleasant affiliative images.

Reduced neural activity when anticipating social versus nonsocial rewards in schizophrenia: Preliminary evidence from an ERP study.

Diminished social motivation is a core feature of schizophrenia that might reflect disturbances in social reward processing. It is not known whether these disturbances reflect anticipatory ("wanting") and/or consummatory ("liking") pleasure deficits. The primary aim of this study was to examine social versus nonsocial reward processing during these temporally distinct substages using event-related potential (ERP) components. Twenty-three schizophrenia participants and 20 healthy participants completed an incentive delay task with social (i.e., smiling expressions) and nonsocial (i.e., money) rewards. We measured two anticipatory ERPs (i.e., "wanting") (target anticipation: Contingent Negative Variation [CNV]; feedback anticipation: Stimulus Preceding Negativity [SPN]) and one consummatory ERP (i.e., "liking") (feedback receipt: P300). As a secondary aim, we examined correlations between the ERPs and interview-rated motivational negative symptoms and social functioning. Schizophrenia participants showed overall less target anticipation (blunted CNV) across all trials (social and nonsocial) than healthy participants. Importantly, schizophrenia participants exhibited less anticipation of social rewards relative to nonsocial rewards (SPN), whereas healthy participants showed similar anticipation for both reward types. Both groups showed similar responses to social and nonsocial reward receipt (P300). Furthermore, social reward anticipation during the incentive delay task was associated with more social approach behaviors in the real-world. Together, these findings provide preliminary evidence for intact social reward "liking" and impaired "wanting" in schizophrenia.

Racial differences in the psychosocial response to the COVID-19 pandemic in veterans with psychosis or recent homelessness.

The COVID-19 pandemic continues to disproportionately impact people of color and individuals experiencing psychosis and homelessness. However, it is unclear whether there are differences by race in psychosocial responses to the pandemic in vulnerable populations. The double jeopardy hypothesis posits that multiply marginalized individuals would experience worse psychosocial outcomes. The present study investigated the clinical and functional initial responses to the pandemic in both Black (n = 103) and White veterans (n = 98) with psychosis (PSY), recent homelessness (RHV), and in a control group (CTL) enrolled in Department of Veterans Affairs (VA) healthcare services. Clinical interviews were administered via phone at two time points: baseline (mid-May through mid-August 2020) and follow-up (mid-August through September 2020). The baseline interview also included retrospective measures of pre-COVID status from January 2020. There were no significant differences between Black and White veterans in depression, anxiety, or loneliness. However, Black veterans did endorse more fears of contamination, F(1, 196.29) = 9.48, p = .002. Across all groups, Black veterans had better family integration compared to White veterans, F(1, 199.98) = 7.62, p = .006. There were no significant differences by race in social integration, work/role productivity, or independent living. In sum, there were few significant differences between Black and White veterans in initial psychosocial response to the pandemic. The lack of racial disparities might reflect the presence of VA's wrap-around services. The findings also highlight the robust nature of social support in Black veterans, even in the context of a global pandemic. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Examining racial differences in community integration between black and white homeless veterans.

Black Americans are overrepresented in Veteran and non-Veteran homeless populations. Community integration remains a problem for many Veterans after they obtain housing, and Black Veterans may encounter additional difficulties due to systemic racism. However, no prior study has specifically examined whether there are racial differences in community integration; similarly, no study has considered racial differences in psychosocial correlates of community integration in homeless Veterans. Knowledge of these factors could inform the development of culturally congruent rehabilitative interventions for Black Veterans. Semi-structured clinical interviews were administered to Black (N = 99) and White (N = 49) homeless Veterans to examine relations among psychiatric symptoms, motivation, and community integration domains (e.g., social integration, work productivity, and independent living). There were no significant racial differences in independent living or work productivity. Black Veterans had better social integration with family compared to White Veterans. In addition, psychiatric symptoms were more strongly correlated with social integration for Black than White Veterans. The association between motivation and work productivity was also stronger for Black Veterans. Recovery-oriented interventions could harness family connections and better target psychiatric symptoms to improve community integration for Black Veterans. Work productivity may improve from interventions aimed at enhancing motivation for Black Veterans.

Motivational and cognitive factors linked to community integration in homeless veterans: study 1 - individuals with psychotic disorders.

BACKGROUND: Little is known about the determinants of community integration (i.e. recovery) for individuals with a history of homelessness, yet such information is essential to develop targeted interventions. METHODS: We recruited homeless Veterans with a history of psychotic disorders and evaluated four domains of correlates of community integration: perception, non-social cognition, social cognition, and motivation. Baseline assessments occurred after participants were engaged in supported housing services but before they received housing, and again after 12 months. Ninety-five homeless Veterans with a history of psychosis were assessed at baseline and 53 returned after 12 months. We examined both cross-sectional and longitudinal relationships with 12-month community integration. RESULTS: The strongest longitudinal association was between a baseline motivational measure and social integration at 12 months. We also observed cross-sectional associations at baseline between motivational measures and community integration, including social, work, and independent living. Cross-lagged panel analyses did not suggest causal associations for the motivational measures. Correlations with perception and non-social cognition were weak. One social cognition measure showed a significant longitudinal correlation with independent living at 12 months that was significant for cross-lagged analysis, consistent with a causal relationship and potential treatment target. CONCLUSIONS: The relatively selective associations for motivational measures differ from what is typically seen in psychosis, in which all domains are associated with community integration. These findings are presented along with a partner paper (Study 2) to compare findings from this study to an independent sample without a history of psychotic disorders to evaluate the consistency in findings regarding community integration across projects.

The viability of the frequency following response characteristics for use as biomarkers of cognitive therapeutics in schizophrenia.

Deficits in early auditory information processing contribute to cognitive and psychosocial disability; this has prompted development of interventions that target low-level auditory processing, which may alleviate these disabilities. The frequency following response (FFR) is a constellation of event-related potential and frequency characteristics that reflect the processing of acoustic stimuli at the level of the brainstem and ascending portions of the auditory pathway. While FFR is a promising candidate biomarker of response to auditory-based cognitive training interventions, the psychometric properties of FFR in schizophrenia patients have not been studied. Here we assessed the psychometric reliability and magnitude of group differences across 18 different FFR parameters to determine which of these parameters demonstrate adequate internal consistency. Electroencephalography from 40 schizophrenia patients and 40 nonpsychiatric comparison subjects was recorded during rapid presentation of an auditory speech stimulus (6000 trials). Patients showed normal response amplitudes but longer latencies for most FFR peaks and lower signal-to-noise ratios (SNRs) than healthy subjects. Analysis of amplitude and latency estimates of peaks, however, indicated a need for a substantial increase in task length to obtain internal consistency estimates above 0.80. In contrast, excellent internal consistency (>0.95) was shown for FFR sustained responses. Only SNR scores reflecting the FFR sustained response yielded significant group differences and excellent internal consistency, suggesting that this measure is a viable candidate for use in clinical treatment studies. The present study highlights the use of internal consistency estimates to select FFR characteristics for use in future intervention studies interested in individual differences among patients.