Hearing Loss in Older People With Schizophrenia: Audiologic Characteristics and Association With Psychosocial Functioning

OBJECTIVE

The severity and impact of hearing deficits among adults with schizophrenia spectrum disorders may become increasingly relevant with advancing age. This study evaluated hearing ability and associated psychosocial functioning among older adults aged 50-70.

DESIGN

Cross-sectional analysis.

SETTING

Four outpatient psychiatry clinics in New York City.

PARTICIPANTS

Individuals aged 50-70 years with diagnoses of schizophrenia or schizoaffective disorder.

MEASUREMENTS

Unaided pure tone air conduction audiometry conducted using a portable audiometry system determined the pure tone average (PTA) hearing threshold across four frequencies: 500, 1k, 2k, and 4k Hz. Better ear PTA defined the hearing threshold. Audiometry data retrieved from the U.S. National Health and Nutrition Examination Survey aided interpretation of sample hearing loss rates. Standard measures evaluated psychiatric symptoms, perceived impact of hearing impairment, loneliness, and quality of life.

RESULTS

Among audiometry completers (N = 40), 35% (n = 14) demonstrated subclinical hearing loss (16-25 dB) and 35% (n = 14) had mild or worse hearing loss (≥26 dB). Rates were higher than expected based on age-based population data. Those who perceived hearing handicap rated it moderate (12.2%) or severe (7.3%); those who perceived tinnitus rated the impact as mild to moderate (12.2%) or catastrophic (2.4%). Neither psychiatric symptoms nor interviewer-rated quality of life was associated with hearing ability. Greater loneliness was significantly correlated with worse audiologic performance (r = 0.475, p <0.01) and greater perceived hearing handicap (r = 0.480, p <0.01).

CONCLUSION

Identifying the need for hearing loss treatment among aging adults with schizophrenia spectrum disorders is important given the potential implications for social functioning, cognitive, and mental health.

Implementation of Cognitive Health Services in Large Systems of Care: Highlights From Coordinated Specialty Care for First Episode Psychosis

BACKGROUND AND HYPOTHESIS

With increasing recognition of the importance of cognitive health for recovery in people with psychosis, questions arise as to how to implement cognitive health services in large systems of care. This paper describes the implementation of cognitive health services in OnTrackNY (OTNY), a network of clinics delivering a Coordinated Specialty Care treatment model for early psychosis, with the goal of documenting the processes, challenges, and useful adaptations.

STUDY DESIGN

In 2018, OTNY piloted a Cognitive Health Toolkit for implementation across 18 affiliated clinics. The toolkit intended to identify the cognitive health needs of individuals early in the course of psychosis and to integrate cognitive health into the vocabulary of wellness and recovery. Implementation involved creating mechanisms for staff training and support to, in turn, help participants improve how they use cognitive skills in daily life.

STUDY RESULTS

The toolkit was disseminated to all 28 OTNY programs throughout New York state by 2023. When simple assessment and decision-making tools were embedded in routine care practices, the majority of participants identified that improving memory, attention, and critical thinking skills would be helpful. Consistently, about 70% of those asked wanted to learn more about how to better their cognitive health.

CONCLUSIONS

Cognitive health services can be implemented in large systems of care that provide a multi-level system of implementation supports. Organizational facilitators of implementation include a training program to educate about cognitive health and the delivery of cognitive health interventions, and embedded quality assurance monitoring and improvement activities.

Correlates of hearing loss among adults with schizophrenia

BACKGROUND

Hearing loss (HL) is associated with adverse cognitive, mental, and physical health outcomes. There is evidence that across age groups HL is more prevalent in people with schizophrenia than the general population. Given that people with schizophrenia may already be vulnerable to cognitive and psychosocial disability, we sought to examine how hearing ability relates to concurrent levels of cognitive, mental and daily functioning.

METHODS

Community-dwelling adults with schizophrenia (N = 84) ages 22-50 completed pure tone audiometry assessments. Hearing threshold (in decibels) was defined as the lowest detectable pure tone at 1000 Hz. Pearson correlation was used to test the hypothesis that higher hearing thresholds (worse hearing) would be significantly associated with poorer performance on the Brief Assessment of Cognition in Schizophrenia (BACS). Additional analyses explored the relationships between audiometric threshold and functional capacity measured with the Virtual Reality Functional Capacity Assessment Tool (VRFCAT) and symptoms severity rated on the Positive and Negative Syndrome Scale (PANSS).

RESULTS

Hearing threshold was inversely and significantly correlated with the BACS composite score (r = -0.27, p = 0.017). This relationship was reduced but remained significant after controlling for age (r = -0.23, p = 0.04). Hearing threshold was not associated with VRFCAT or psychiatric symptom measures.

CONCLUSIONS

While schizophrenia and HL are independently associated with cognitive impairment, the magnitude of impairment in this sample was greater among those with poorer hearing. Findings warrant further mechanistic study of the relationship between hearing impairment and cognition and have implications for addressing modifiable health risk factors for higher morbidity and mortality in this vulnerable population.

Early auditory processing dysfunction in schizophrenia: Mechanisms and implications

Schizophrenia is a major mental disorder that affects approximately 1% of the population worldwide. Cognitive deficits are a key feature of the disorder and a primary cause of long-term disability. Over the past decades, significant literature has accumulated demonstrating impairments in early auditory perceptual processes in schizophrenia. In this review, we first describe early auditory dysfunction in schizophrenia from both a behavioral and neurophysiological perspective and examine their interrelationship with both higher order cognitive constructs and social cognitive processes. Then, we provide insights into underlying pathological processes, especially in relationship to glutamatergic and N-methyl-D-aspartate receptor (NMDAR) dysfunction models. Finally, we discuss the utility of early auditory measures as both treatment targets for precision intervention and as translational biomarkers for etiological investigation. Altogether, this review points out the crucial role of early auditory deficits in the pathophysiology of schizophrenia, in addition to major implications for early intervention and auditory-targeted approaches.

Dose-Dependent Augmentation of Neuroplasticity-Based Auditory Learning in Schizophrenia: A Double-Blind, Placebo-Controlled, Randomized, Target Engagement Clinical Trial of the NMDA Glutamate Receptor Agonist d-serine

BACKGROUND

Patients with schizophrenia show reduced NMDA glutamate receptor-dependent auditory plasticity, which is rate limiting for auditory cognitive remediation (AudRem). We evaluate the utility of behavioral and neurophysiological pharmacodynamic target engagement biomarkers, using a d-serine+AudRem combination.

METHODS

Forty-five participants with schizophrenia or schizoaffective disorder were randomized to 3 once-weekly AudRem visits + double-blind d-serine (80, 100, or 120 mg/kg) or placebo in 3 dose cohorts of 12 d-serine and 3 placebo-treated participants each. In AudRem, participants indicated which paired tone was higher in pitch. The primary outcome was plasticity improvement, operationalized as change in pitch threshold between AudRem tones [(test tone Hz - reference tone Hz)/reference tone Hz] between the initial plateau pitch threshold (mean of trials 20-30 of treatment visit 1) to pitch threshold at the end of visit(s). Target engagement was assessed by electroencephalography outcomes, including mismatch negativity (pitch primary).

RESULTS

There was a significant overall treatment effect for plasticity improvement (p = .014). Plasticity improvement was largest within the 80 and 100 mg/kg groups (p < .001, d > 0.67), while 120 mg/kg and placebo-treated participants showed nonsignificant within-group changes. Plasticity improvement was seen after a single treatment and was sustained on subsequent treatments. Target engagement was demonstrated by significantly larger mismatch negativity (p = .049, d = 1.0) for the 100 mg/kg dose versus placebo.

CONCLUSIONS

Our results demonstrate sufficient proof of principle for continued development of both the d-serine+AudRem combination and our target engagement methodology. The ultimate utility is dependent on the results of an ongoing larger, longer study of the combination for clinically relevant outcomes.

Hearing Loss Among People With Schizophrenia: Implications for Clinical Practice

OBJECTIVE

The authors characterized hearing loss among individuals diagnosed as having schizophrenia to inform provision of routine behavioral health services to this population.

METHODS

Audiometry data collected between October 2019 and December 2021 from 84 community-dwelling adults with schizophrenia and 81 age-matched participants without the condition were analyzed. Rates of hearing loss were identified within groups and across age decades (20-50 years). Hearing threshold and rates of hearing loss were compared between groups.

RESULTS

Participants with schizophrenia had significantly higher mean hearing thresholds (p=0.006), indicating worse hearing. This difference remained significant after controlling for age (p=0.01). A significantly larger proportion of participants with schizophrenia had mild hearing loss (24%) compared with age-matched participants (6%) (p=0.002), with higher rates of mild hearing loss observed across all ages.

CONCLUSIONS

Screening for and detection of hearing loss among adults with schizophrenia may be an unmet need. Hearing loss is a treatable source of cognitive and psychosocial disability, warranting scalable assessment and intervention practices.

Toolkit for assessing and addressing cognitive health in early psychosis: Evaluation of feasibility and utility in a coordinated specialty care setting

AIM

Methods to identify and harness individual cognitive strengths while addressing relative weaknesses have the potential to complement recovery services for first-episode psychosis but systematic implementation is needed. We developed a cognitive health toolkit, trained teams from OnTrackNY, a network of coordinated specialty care (CSC) programs and examined toolkit feasibility and clinical utility during the first year of roll-out.

METHODS

The toolkit includes a clinician manual, assessment and decision-making tools, and a menu of cognitive health service options. Assessment uses the WRAT5-Reading subtest and a new Self-Assessment of Cognitive Functioning which, together, determine participant- and clinician-perceived cognitive health need. Program-level data were analysed for rates of assessment, identification of cognitive health needs and cognitive health service provision.

RESULTS

Data from 18 OnTrackNY teams included 933 participants, including 310 new admissions. Across teams, 43.9% of newly admitted participants received a WRAT5-Reading and 41.3% received a self-assessment. Of all assessments completed in the study period, 50.7% were at or within 3-months of admission and 69.1% were within the first year of program participation. Cognitive health need was identified by self-report (57.6%) and clinician-report (69.9%) and led to provision of specific services, including psychoeducation, compensatory skills training and in some cases restorative cognitive training.

CONCLUSIONS

Preliminary feasibility data are encouraging but barriers to assessment need to be identified and addressed. Rates of identified cognitive health need warrant further study of the implementation process and outcomes so that cognitive health assessment and treatment practices may ultimately be disseminated to CSC programs more broadly.

Feasibility and acceptability of remotely accessed cognitive remediation for schizophrenia in public health settings

Cognitive remediation (CR) is an evidence-based therapy used to improve cognition in people with schizophrenia. However, it often requires multiple in-person clinic sessions per week, which can limit scalability. This mixed methods study considered the feasibility and acceptability of a hybrid approach, which allowed for half the sessions to be conducted remotely as homework, without the clinician present. Individuals with schizophrenia were randomized to either all in-clinic or hybrid conditions and completed questionnaires and individual interviews about their experience. CR clinicians provided feedback in complement. Because of limited access to technology, most Hybrid CR participants had to come to clinic to access computers and often sought clinician support to do their homework. Participants in the two conditions were equally satisfied per the Client Satisfaction Questionnaire, and the majority reported perceived benefit and enjoyment. Both CR participants and clinicians identified access to technology as a barrier to program feasibility, while availability of clinician support positively impacted acceptability. Suggestions to improve CR highlighted adopting a flexible approach to providing CR that accounts for participant access to technology, potential benefit from peer interaction, and need for clinician support.

Predicting response to cognitive training for schizophrenia using results from two studies with different outcomes

BACKGROUND

Collaborative data sharing between research groups provides an opportunity to explore the basis for the heterogeneity in cognitive training outcomes reported in the schizophrenia literature. The current analyses focused on the contribution of site and participant characteristics to these heterogeneous outcomes.

METHODS

Data from two independent studies, from New York (NY) and Los Angeles (LA), were combined to yield a sample of 132 outpatient adults with schizophrenia/schizoaffective disorder. While similar treatment doses, cognitive exercises and outcome measures were used, sites differed in use of coaching, group discussion and compensation. Between-site differences in participant demographic and baseline clinical characteristics were tested. Regression examined predictors of change in cognition (MCCB) and functional capacity (UPSA) which could explain site differences in treatment effects.

RESULTS

Medium to large treatment effect size differences in MCCB and UPSA favored the NY site over LA. When the studies were combined, the effect of site was significant for both outcomes with a medium effect size difference. After controlling for background characteristics, the effect of site was reduced for both outcomes, but remained significant for cognition. Improvement in UPSA was associated with better baseline MCCB (p < 0.001), lower baseline UPSA (p < 0.001) and younger age (p = 0.019). The overall model with site, baseline scores, and participant background characteristics explained about 30% to 40% of the variance in outcomes.

DISCUSSION

Participant and treatment characteristics are both predictive of outcomes, but treatment characteristics may be more consequential to cognitive gain, while participant characteristics may be more consequential to change in functional capacity.

Addressing cognitive health in coordinated specialty care for early psychosis: Real-world perspectives

AIM

Addressing cognitive health during the early phase of psychosis has the potential to enhance recovery outcomes, yet methods to assess and treat cognitive problems are not a systematic part of Coordinated Specialty Care (CSC) in the United States. We sought to understand how CSC providers perceive cognitive health and gauge the acceptability and appropriateness of cognitive interventions to inform the development and implementation of a cognitive health toolkit for OnTrackNY, a CSC program.

METHODS

Electronic surveys were sent to clinicians from 22 OnTrackNY teams. One unstructured and 10 structured questions assessed knowledge and beliefs about cognition, current cognitive health practices, the likelihood of adopting new practices, perceived facilitators, and barriers to assessing and treating cognitive health.

RESULTS

Fifty-three clinicians responded. Clinicians identified a range of terms associated with cognitive impairment with specific neurocognitive deficits cited most frequently. The majority perceived the evidence for cognitive impairment at the time of first episode to be moderate to strong, that specific interventions for cognition are warranted, and that there is a significant link between cognition and community functioning. While current practices vary, 88% indicated a high likelihood of integrating tools to address cognitive problems if provided. Compensatory approaches to aid cognitive functioning were viewed most favourably.

CONCLUSIONS

Results suggest that addressing cognitive health is acceptable and appropriate for OnTrackNY but there is a need for systematic training to integrate empirically supported interventions with existing recovery-oriented practices. Piloting a cognitive health toolkit will inform the potential uptake of assessment and treatment practices more broadly.

The cognitive training version of the MUSIC® model of motivation inventory: A follow-up validity study

Further validation of the MUSIC® Model of Motivation Inventory (MMI) for use in Cognitive Remediation (CR) for schizophrenia is needed. The MMI was compared to the Intrinsic Motivation Inventory - Schizophrenia Research and Perceived Competency Scale following early treatment exposure in a CR clinical trial. MMI Usefulness, Success, and Interest scales were significantly correlated with corresponding comparison scales. The MMI was not correlated with pre-morbid cognitive ability. Higher expectancy for success and perceived usefulness were significantly associated with greater intensity of session attendance. Results support the convergent, divergent, and predictive validity of the MMI for CR research and clinical use.

Cognitive remediation for schizophrenia: An expert working group white paper on core techniques

Cognitive remediation is now widely recognized as an effective treatment for cognitive deficits in schizophrenia. Its effects are meaningful, durable, and related to improvements in everyday functional outcomes. As with many therapies, the evolution of cognitive remediation has resulted in treatment programs that use a variety of specific techniques, yet share common core principles. This paper is the product of a cognitive remediation expert working group consensus meeting to identify core features of the treatment and produce recommendations for its design, conduct, reporting, and implementation. Four techniques were identified as core features of cognitive remediation: facilitation by a therapist, cognitive exercise, procedures to develop problem-solving strategies, and procedures to facilitate transfer to real world functioning. Treatment techniques within each of these core features are presented to facilitate decisions for clinical trials and implementation in clinical settings.

Impact of baseline early auditory processing on response to cognitive remediation for schizophrenia

BACKGROUND

Early auditory processing (EAP) has increasingly become a focus of efforts to identify biomarkers of treatment response in schizophrenia. EAP deficits lead to poor functional outcome via impaired cognition, and treatments that target EAP may drive downstream cognitive improvements. Assessment of baseline need provides an opportunity for cognitive remediation (CR) programs that give EAP training to personalize treatment and optimize its impact. This initial efficacy study examined the differential benefit of EAP training for those with and without baseline EAP deficits as defined by performance on the Tone Matching Test.

METHODS

103 outpatient adults diagnosed with schizophrenia or schizoaffective disorder were classified as having intact (48.5%) or impaired (51.5%) EAP and randomized to a CR program with restorative exercise plans that either included EAP training (N = 49) or did not (N = 54). Cognitive and functional outcomes were measured post-treatment and 3 months later.

RESULTS

Only in EAP impaired participants was there a significant benefit from EAP training on verbal learning. Treatment condition did not significantly impact global cognitive or functional outcomes for either EAP group. Cognitive gains partially mediated the relationship between gains in EAP and functional capacity.

CONCLUSION

These findings support the importance of addressing basic auditory deficits when attempting to remediate higher order auditory impairments such as verbal learning. In addition, they highlight the need for routine assessment of EAP in cognitive remediation participants, as well as the need for more effective programs to reverse these impairments.

Translating cognitive behavioral interventions from bench to bedside: The feasibility and acceptability of cognitive remediation in research as compared to clinical settings

Cognitive remediation (CR) research typically addresses internal validity, and few studies consider CR in a real-world context. This study evaluated the fit between the program conditions and treatment model in research and clinical settings, with the goal of informing future research on the contextual challenges associated with the implementation of CR. Data was drawn from an initiative by New York State's Office of Mental Health (OMH), to implement CR programs for adults with Serious Mental Illness (SMI) in 16 state operated outpatient clinics. One of these clinics first became a research site for a CR randomized clinical trial, which allowed for a comparison of the feasibility and acceptability of CR in a research as compared to a clinical setting. RESULTS: The research site averaged almost triple the number of referrals as the clinical sites. Over nine months 46.51% of clinic referrals were enrolled in the CR program whereas 64.29% of research referrals were enrolled. Clinical site utilization averaged 70.53% while research site utilization averaged 90.47%. At the clinical sites, 97% of respondents reported CR was an excellent or good experience. There was high treatment fidelity for program structure and content across sites. CONCLUSIONS: This comparison of CR in clinical and research sites highlights the decrease in referrals, enrollment and utilization that occurs when a program moves from a highly controlled setting to the real world. Still, the acceptability, fill rates and utilization indicated that CR can be successfully implemented in large scale, geographically diverse, publically funded clinic settings.

Personalised treatment for cognitive dysfunction in individuals with schizophrenia spectrum disorders

Cognitive deficits are a well-recognised issue for individuals diagnosed with schizophrenia spectrum disorders. Despite positive group findings for the use of cognitive remediation (CR) interventions, there are substantial individual differences in response to treatment. In addition, the aggregate CR literature reports low moderate effect sizes for cognitive and functional outcomes. Based on personalised medicine theory, this paper uses extant CR literature to examine the individual characteristics determined to predict treatment response. These characteristics, which fall into the broad categories of cognitive, psychological, and biological can be used as tailoring variables to personalise CR to an individual's unique profile. Personalisation through the use of these tailoring variables has the potential to improve the delivery of CR to maximise treatment outcomes.

The Role of Motivation in Cognitive Remediation for People with Schizophrenia

Motivation impairment is an often prominent component of schizophrenia symptomatology that impacts treatment engagement and reduces the functional benefit from psychosocial interventions. Intrinsic motivation in particular has been shown to be impaired in schizophrenia. Nowhere is the role of intrinsic motivation impairment more evident than in cognitive remediation for schizophrenia. This chapter describes the theoretical determinants of motivation to learn and illustrates how those determinants have been translated into therapeutic techniques that enhance intrinsic motivation in a clinical context. We review the extant research that indicates how motivation enhancing techniques yield treatment-related improvements within cognitive remediation therapy and, more broadly, in other behavioral skills-based interventions for schizophrenia.

Cognitive deficit and mental health in homeless transition-age youth

BACKGROUND AND OBJECTIVES

There is increasing recognition of the cognitive consequences of socioeconomic adversity during childhood, which can impair learning and negatively affect social and emotional development. However, there is a paucity of research on cognitive functioning and mental health among transition-age homeless youth. This study aimed to address this knowledge gap by examining the prevalence and functional significance of cognitive impairment and mental health disorders in a sample of 18- to 22-year-old homeless youth.

METHODS

Participants (N = 73) were recruited from a vocational support program at Covenant House New York, a care agency for homeless youth. Assessments included diagnostic assessment for mental health disorders and evaluation of neurocognition and vocational outcomes.

RESULTS

Youth demonstrated histories of academic instability, academic achievement below expectation, and high rates of untreated psychiatric disorders, the most prominent of which were anxiety, substance use, and mood disorders. Of those who had a mental health diagnosis, more than half demonstrated cognitive deficits. Performance on measures of working memory and verbal memory was <70% of that of the age-matched normative population. Cognitive impairment was associated with a significant risk for making a wage insufficient for independent living.

CONCLUSIONS

These data confirm the need to focus on cognitive as well as emotional and physical health in transition-age youth. Comprehensive intervention at this later developmental stage has the potential to facilitate the acquisition of skills needed for academic, vocational, and independent living success in adulthood.

Current trends in the empirical study of cognitive remediation for schizophrenia

Cognitive remediation (CR) for schizophrenia is a learning-based behavioural skills training intervention designed to enhance neuro and (or) social cognitive skills, with the ultimate goal of generalization to improve psychosocial outcomes. This review summarizes conceptual approaches to CR for schizophrenia and the evidence for efficacy in clinical research settings. Four issues are at the forefront of ongoing research: the identification of techniques that produce the largest cognitive change, delineation of techniques that enhance transfer of cognitive skills to functional skills, the identification of CR methods that can be personalized to meet the specific cognitive and functional needs of each individual, and, all the while, ensuring that when CR methods are developed in a research setting, they remain scalable for delivery in the larger clinical community. In response to these issues, 3 prominent research trends have emerged: the rise of a new generation of computerized restorative cognitive training, the integration of CR with skills training to promote generalization, and the application of techniques to enhance motivation and learning during CR. As data on the neural basis of learning in people with schizophrenia become available, new technologies that harness the ability of the brain to make sustainable, functional changes may be integrated within a therapeutic context that promotes a personalized approach to learning. The development of transportable and scalable methods of CR that maximize the ability of people with schizophrenia to improve cognition will help them achieve personal goals for recovery.

The relationship of trait to state motivation: the role of self-competency beliefs

Even when people with schizophrenia describe themselves as generally motivated and eager to engage in activities, they may not actually be motivated in the present moment. In order to better understand the relationship between trait and state motivation, we aimed to assess trait motivation and state intrinsic motivation, and investigate their relations to each other and to criterion-related variables including cognition, negative symptoms, and beliefs about one's own competency-also known as perceived competency (PC). Further, we investigated whether PC mediates the relationships between state intrinsic motivation (IM) and trait motivation dimensions. Forty individuals with schizophrenia or schizoaffective disorders were administered two self-report measures of motivation, the Motivational Trait Questionnaire (Kanfer, R., Ackerman, P., 2000. Individual differences in work motivation: further explorations of a trait framework. Appl. Psychol. 49 (3), 470-482) and the Intrinsic Motivation Inventory for Schizophrenia Research (Choi, J., Medalia, A., 2010. Intrinsic motivation and learning in a schizophrenia spectrum sample. Schizophr. Res. 118, 12-19), as well as measures of PC, cognition and symptoms. The results showed that in people with schizophrenia, trait approach motivation, but not trait avoidance motivation, is positively correlated with state intrinsic motivation and PC. There was evidence that PC partially mediates the relationship between trait approach motivation and state intrinsic motivation to do the task. These results support the role of therapies that directly address self-competency beliefs and set the groundwork for future investigations on the impact of such treatments on motivation.

Neuropsychology of the deficit syndrome: new data and meta-analysis of findings to date

The deficit syndrome is thought to characterize a pathophysiologically distinct subgroup of patients with schizophrenia. Supporting this notion, prior research examining the neuropsychological correlates of the deficit syndrome has suggested the presence of a differential impairment in frontal and parietal functions. This article reports findings from 2 studies attempting to replicate and extend previous reports of a differential neuropsychological impairment in deficit schizophrenia. In the first study, we administered a comprehensive neuropsychological battery to 20 deficit and 25 nondeficit patients with schizophrenia and 25 normal healthy controls. In the second study, a meta-analysis was conducted of 13 separate studies examining the neuropsychology of the deficit syndrome. There was little evidence from either of the present studies that the deficit syndrome is associated with a selective impairment in frontal and parietal lobe functions. The first study failed to find significant differences in frontal or parietal abilities for deficit vs nondeficit patients. The meta-analytic findings revealed that deficit patients were globally more neuropsychologically impaired than nondeficit patients (effect size [ES] = 0.41). Relative to nondeficit patients, deficit patients performed poorest on tests of olfaction (ES = 1.11), social cognition (ES = 0.56), global cognition (ES = 0.52), and language (ES = 0.51). The neuropsychological impairments associated with the deficit form of schizophrenia do not follow an obvious anatomically defined pattern of impairment. The question of whether deficit patients exhibit a unique cognitive impairment profile will require a more sophisticated and rigorous examination of the neuropsychology of the deficit syndrome.

A new dimension of sensory dysfunction: stereopsis deficits in schizophrenia

BACKGROUND

Schizophrenia is a neurocognitive disorder with a wide range of cognitive and sensory impairments. Early visual processing has been shown to be especially impaired. This article investigates the integrity of binocular depth perception (stereopsis) in schizophrenia.

METHODS

Seventeen schizophrenia patients and 19 healthy control subjects were compared on the Graded Circles Stereo Test. Results of stereoacuity were compared between patients and control subjects using t test.

RESULTS

Schizophrenia patients demonstrated significantly (p = .006) reduced stereoacuity (mean = 142 arcseconds) versus control subjects (mean = 55 arcseconds). At the normative level for adults, patients performed below chance.

CONCLUSIONS

These findings demonstrate an impairment of binocular depth perception and further confirm deficits of early visual processing in schizophrenia. Findings are discussed in context of magnocellular/dorsal stream processing with implications for visual processing and cognitive deficits.

Neuropsychological functioning and social anhedonia: results from a community high-risk study

Social anhedonia has shown promise as a vulnerability marker for schizophrenia-spectrum pathology. Validity data have come, in part, from findings indicating that cognitive deficits occurring in schizophrenia are also evident in individuals with elevated levels of social anhedonia. However, prior research on this topic has been limited because it has been based almost exclusively on the study of selective samples of college students. The present article reports baseline findings of neuropsychological functioning in social anhedonics and controls from a representative community sample. Data on a wide array of neuropsychological abilities from 18-19 year-old participants with (n = 85) vs. without (n = 87) elevated levels of social anhedonia were analyzed. We hypothesized that, compared to controls, social anhedonics would show impairments in memory and sustained attention. Additionally, we sought to determine if more severe cognitive impairment in anhedonics was associated with greater schizophrenia-spectrum pathology and poorer overall functioning. Compared to controls, socially anhedonic participants performed more poorly on two visual-spatial memory tasks and a test of visual-spatial construction. The groups did not statistically differ on any of the other neuropsychological measures including general cognitive ability and sustained attention. Group differences were not the result of depression, bipolar or substance abuse disorders. Neuropsychological functioning showed little relationship to current clinical symptoms and functioning. Longitudinal assessment of these participants as they move through the risk period should provide important insights into the neuropsychological correlates of the schizophrenia prodrome.

Spatial working memory as a cognitive endophenotype of schizophrenia: assessing risk for pathophysiological dysfunction

Research suggests that first-degree relatives and individuals with schizophrenia spectrum personality disorders (SSPD) may represent nonpenetrant carriers of the genetic diathesis for schizophrenia. This study examined visuospatial working memory (SWM) as a cognitive endophenotype of schizophrenia by expanding the concept of risk for pathophysiological dysfunction beyond overt psychosis. Risk was thus defined by familial status and the presence or absence of SSPD. SWM was assessed in the following groups, in order of decreasing likelihood of genetic vulnerability: 23 patients with schizophrenia, 17 SSPD relatives of patients with schizophrenia, 23 non-SSPD relatives of patients with schizophrenia, 14 SSPD community members with no family history of psychosis, and 36 non-SSPD community members. SWM performance during a computer task was quantified by A-Prime. Relative risk ratios for SWM deficits were compared among the groups. Compared with community non-SSPD volunteers, relative risk (RR) of SWM deficits was significantly elevated in patients with schizophrenia (RR = 3.76, p = .002) and SSPD family members (RR = 2.97, p = .027), but not in the family non-SSPD (RR = 1.88, p = .241) or community SSPD (RR = 1.03, p = .971) groups. The pattern of SWM performance deficits reflected the proposed model of latent genetic liability, upholding SWM as a viable cognitive endophenotype. The results underscore the importance of including both familial liability and the schizophrenia spectrum when considering risk for schizophrenia and schizophrenia-related traits. This is particularly relevant for research efforts to identify pathophysiological components of the disease.

Impairments in generation of early-stage transient visual evoked potentials to magno- and parvocellular-selective stimuli in schizophrenia

OBJECTIVE

Patients with schizophrenia demonstrate significant impairments of early visual processing, potentially implicating dysfunction of the magnocellular visual pathway. The present study evaluates transient visual evoked potential (tVEP) responses to stimuli biased toward the magnocellular (M) or parvocellular (P) systems in patients with schizophrenia vs. normal volunteers first to evaluate relative contributions of M and P systems to specific tVEP components in schizophrenia and, second, to evaluate integrity of early M and P processing in schizophrenia.

METHODS

Seventy-four patients with schizophrenia and schizoaffective disorder were compared with 59 control subjects using separate stimuli to assess the tVEP response to M, P and mixed M/P conditions. Stimuli were biased toward M vs. P processing by manipulation of chromatic and achromatic contrast. C1, P1, N1 and P2 components were compared between patients and controls. All subjects showed 20/32 vision or better.

RESULTS

Waveforms were obtained to low contrast (M), chromatic contrast (P) and high contrast (mixed M/P) stimuli in both patients and controls. C1 was present to P and mixed M/P stimuli. Patients showed a significant reduction in amplitude and an increase in latency of the C1 component. P1 was elicited primarily by M and mixed M/P stimuli, whereas N1 was elicited primarily by P and mixed M/P stimuli. Patients showed reductions in both P1 and N1 amplitudes across conditions. However, only reductions in P1 amplitude survived covariation for between group differences in visual acuity. Further, P1 amplitude reductions in the M condition correlated with a proxy measure of global outcome.

CONCLUSIONS

M- and P-selective stimuli elicit differential components of the tVEP. Patients with schizophrenia show significant reductions in response even to simple visual stimuli. Deficits, particularly within the M system, may correlate significantly with global outcome and level of community functioning.

SIGNIFICANCE

Whereas deficits in high-order cognitive processing have been extensively documented in schizophrenia, integrity of early-stage sensory processing has been studied to a lesser degree. The present findings suggest that deficits in early-stage visual processing are significantly related to overall clinical outcome in schizophrenia. Further, between-group differences in visual acuity may influence VEP results, even for subjects with 'normal' vision (20/32 or better).

Early-stage visual processing and cortical amplification deficits in schizophrenia

BACKGROUND

Patients with schizophrenia show deficits in early-stage visual processing, potentially reflecting dysfunction of the magnocellular visual pathway. The magnocellular system operates normally in a nonlinear amplification mode mediated by glutamatergic (N-methyl-D-aspartate) receptors. Investigating magnocellular dysfunction in schizophrenia therefore permits evaluation of underlying etiologic hypotheses.

OBJECTIVES

To evaluate magnocellular dysfunction in schizophrenia, relative to known neurochemical and neuroanatomical substrates, and to examine relationships between electrophysiological and behavioral measures of visual pathway dysfunction and relationships with higher cognitive deficits.

DESIGN, SETTING, AND PARTICIPANTS

Between-group study at an inpatient state psychiatric hospital and outpatient county psychiatric facilities. Thirty-three patients met DSM-IV criteria for schizophrenia or schizoaffective disorder, and 21 nonpsychiatric volunteers of similar ages composed the control group.

MAIN OUTCOME MEASURES

(1) Magnocellular and parvocellular evoked potentials, analyzed using nonlinear (Michaelis-Menten) and linear contrast gain approaches; (2) behavioral contrast sensitivity measures; (3) white matter integrity; (4) visual and nonvisual neuropsychological measures, and (5) clinical symptom and community functioning measures.

RESULTS

Patients generated evoked potentials that were significantly reduced in response to magnocellular-biased, but not parvocellular-biased, stimuli (P = .001). Michaelis-Menten analyses demonstrated reduced contrast gain of the magnocellular system (P = .001). Patients showed decreased contrast sensitivity to magnocellular-biased stimuli (P<.001). Evoked potential deficits were significantly related to decreased white matter integrity in the optic radiations (P<.03). Evoked potential deficits predicted impaired contrast sensitivity (P = .002), which was in turn related to deficits in complex visual processing (P< or =.04). Both evoked potential (P< or =.04) and contrast sensitivity (P = .01) measures significantly predicted community functioning.

CONCLUSIONS

These findings confirm the existence of early-stage visual processing dysfunction in schizophrenia and provide the first evidence that such deficits are due to decreased nonlinear signal amplification, consistent with glutamatergic theories. Neuroimaging studies support the hypothesis of dysfunction within low-level visual pathways involving thalamocortical radiations. Deficits in early-stage visual processing significantly predict higher cognitive deficits.