Amanda McCleery

Cognitive functioning in first-episode schizophrenia: MATRICS Consensus Cognitive Battery (MCCB) Profile of Impairment

BACKGROUND Although many studies have assessed cognitive functioning in first-episode schizophrenia (FESz), the pattern and severity of impairment across cognitive domains remain unclear. Moreover, few studies have directly compared the pattern of cognitive performance between FESz and chronic schizophrenia (CSz). In this study we examined the cognitive impairment profile in FESz using a standardized neurocognitive battery (MATRICS Consensus Cognitive Battery; MCCB). METHODS MCCB data were compared from 105 FESz patients, 176 CSz patients and 300 non-psychiatric (NP) participants. Mixed model analysis evaluated group differences in MCCB profiles and relative strengths and weaknesses in the MCCB profiles of patients. Clinical implications of MCCB performance were also examined; we compared the proportion of participants from each group who exhibited clinically-significant global cognitive impairment based on the MCCB Overall Composite score. RESULTS FESz and CSz showed impaired performance across all MCCB domains relative to NP. With the exception of relative preservation of working memory and social cognition in FESz, the MCCB domain scores were similar in FESz and CSz. The distribution of impairment on the Overall Composite score did not significantly differ between FESz and CSz; compared to NP, both patient groups were overrepresented in moderate and severe impairment categories. CONCLUSION The pattern, magnitude, and distribution of severity of impairment in FESz were similar to that observed in CSz. However, early in the illness, there may be relative sparing of working memory and social cognition.

Latent structure of cognition in schizophrenia: a confirmatory factor analysis of the MATRICS Consensus Cognitive Battery (MCCB)

Background The number of separable cognitive dimensions in schizophrenia has been debated. Guided by the extant factor analytic literature, the NIMH Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) initiative selected seven cognitive domains relevant to treatment studies in schizophrenia: speed of processing, attention/vigilance, working memory, verbal learning, visual learning, reasoning and problem solving, and social cognition. These domains are assessed in the MATRICS Consensus Cognitive Battery (MCCB). The aim of this study was to conduct a confirmatory factor analysis (CFA) of the beta battery of the MCCB to compare the fit of the MATRICS consensus seven-domain model to other models in the current literature on cognition in schizophrenia. Method Using data from 281 schizophrenia outpatients, we compared the seven correlated factors model with alternative models. Specifically, we compared the 7-factor model to ( a ) a single-factor model, ( b ) a three correlated factors model including speed of processing, working memory, and general cognition, and ( c ) a hierarchical model in which seven first-order factors loaded onto a second-order general cognitive factor. Results Multiple fit indices indicated the seven correlated factors model was the best fit for the data and provided significant improvement in model fit beyond the comparison models. Conclusions These results support the assessment of these seven cognitive dimensions in clinical trials of interventions to improve cognition in schizophrenia. Because these cognitive factors are separable to some degree, it is plausible that specific interventions may have differential effects on the domains.

Cross-diagnostic comparison of visual processing in bipolar disorder and schizophrenia

Patients with Schizophrenia (SZ) show deficits across various stages of visual information processing. Whether patients with Bipolar Disorder (BD) exhibit these deficits is unclear. In this study, we conducted a detailed comparison of specific stages of early visual perception in BD and SZ. Forty-three BD patients, 43 SZ patients, and 51 matched healthy control subjects (HC) were administered three visual processing paradigms emphasizing: 1) an early stage of object formation (location backward masking), 2) a middle stage of object substitution (four-dot backward masking), and 3) a later stage at the perception-attention interface (rapid serial visual processing (RSVP) task eliciting the attentional blink). SZ performed significantly worse than BD and HC on location and four-dot masking. BD did not significantly differ from HC on either masking task. Both patient groups performed significantly worse than HC on the RSVP task; unlike SZ, BD did not show a significant attentional blink effect compared to HC. Our results indicate that BD patients were intact at the early and middle stages of visual processing (object formation and substitution) but intermediate between the SZ and HC groups at a later processing stage involving perceptual and attentional processes (RSVP task). These findings suggest that SZ is characterized by a diffuse pathophysiology affecting all stages of visual processing whereas in BD disruption is only at the latest stage involving higher order attentional functions.

Schizotypy, alexithymia, and socioemotional outcomes.

Studies have found higher levels of alexithymia in schizophrenic subjects relative to controls, with an overall higher level of emotional arousal and social withdrawal. The present study is an extension of this research to the assessment of schizotypy in a nonclinical sample. Seventy-two undergraduate students (40 female; 21.6 ± 6.38 years) were recruited to participate in this study. Consistent with earlier research, our results show that both schizotypy and alexithymia are associated with relatively poor socioemotional functioning across the variables of depression, anxiety, social functioning, and overall quality of life. Further, our results show that the significant associations found between alexithymia and these 4 outcome variables was predicated on shared variance with schizotypy. When both alexithymia and schizotypy were regressed onto these variables as independent predictors, the contribution of alexithymia was consistently nonsignificant. The implications of these findings are discussed in terms of hypothesized substrates of alexithymia.

Longitudinal stability of social cognition in schizophrenia: A 5-year follow-up of social perception and emotion processing

BACKGROUND Individuals with schizophrenia exhibit marked and disproportional impairment in social cognition, which is associated with their level of community functioning. However, it is unclear whether social cognitive impairment is stable over time, or if impairment worsens as a function of illness chronicity. Moreover, little is known about the longitudinal associations between social cognition and community functioning. METHOD Forty-one outpatients with schizophrenia completed tests of emotion processing (Mayer-Salovey-Caruso Emotional Intelligence Test, MSCEIT) and social perception (Relationships Across Domains, RAD) at baseline and approximately five years later. Stability of performance was assessed using paired t-tests and correlations. Longitudinal associations between social cognition and community functioning (Role Functioning Scale, RFS) were assessed using cross-lagged panel correlation analysis. RESULTS Performance on the two social cognition tasks were stable over follow-up. There were no significant mean differences between assessment points [ps≥0.20, Cohensds≤|0.20|], and baseline performance was highly correlated with performance at follow-up [ρs≥0.70, ICC≥0.83, ps<0.001]. The contemporaneous association between social cognition and community functioning was moderately large at follow-up [ρ=0.49, p=0.002]. However, baseline social cognition did not show a significant longitudinal influence on follow-up community functioning [z=0.31, p=0.76]. CONCLUSIONS These data support trait-like stability of selected areas of social cognition in schizophrenia. Cross-lagged correlations did not reveal a significant unidirectional influence of baseline social cognition on community functioning five years later. However, consistent with the larger literature, a moderately large cross-sectional association between social cognition and community functioning was observed. Based on stability and cross-sectional associations, these results suggest that social cognition might have short-term implications for functional outcome rather than long-term consequences.

Internal versus external auditory hallucinations in schizophrenia: symptom and course correlates

Introduction. The auditory hallucinations associated with schizophrenia are phenomenologically diverse. “External” hallucinations classically have been considered to reflect more severe psychopathology than “internal” hallucinations, but empirical support has been equivocal. Methods. We examined associations of “internal” versus “external” hallucinations with (1) other characteristics of the hallucinations, (2) severity of other symptoms and (3) course of illness variables, in a sample of 97 stable outpatients with schizophrenia or schizoaffective disorder who experienced auditory hallucinations. Results. Patients with internal hallucinations did not differ from those with external hallucinations on severity of other symptoms. However, they reported their hallucinations to be more emotionally negative, distressing and long-lasting, less controllable and less likely to remit over time. They also were more likely to experience voices commenting, conversing or commanding. However, they also were more likely to have insight into the self-generated nature of their voices. Patients with internal hallucinations were not older, but had a later age of illness onset. Conclusions. Differences in characteristics of auditory hallucinations are associated with differences in other characteristics of the disorder, and hence may be relevant to identifying subgroups of patients that are more homogeneous with respect to their underlying disease processes.

Social Disconnection in Schizophrenia and the General Community

Social disability is a defining characteristic of schizophrenia and a substantial public health problem. It has several components that are difficult to disentangle. One component, social disconnection, occurs extensively in the general community among nonhelp-seeking individuals. Social disconnection is an objective, long-standing lack of social/family relationships and minimal participation in social activities. It is associated with negative health effects, including early mortality, and is distinct from subjective loneliness. These 2 topics, social disability in schizophrenia and social disconnection in the general community, have generated entirely distinct research literatures that differ in their respective knowledge gaps and emphases. Specifically, the consequences of social disability in schizophrenia are unknown but its determinants (ie, nonsocial cognition, social cognition, and social motivation) have been well-examined. Conversely, the health consequences of social disconnection in the general community are well-established, but the determinants are largely unknown. Social disconnection is a condition that presents substantial public health concerns, exists within and outside of current psychiatric diagnostic boundaries, and may be related to the schizophrenia spectrum. A comparison of these 2 literatures is mutually informative and it generates intriguing research questions that can be critically evaluated.

Social Cognition during the Early Phase of Schizophrenia

Individuals with chronic schizophrenia exhibit performance deficits on tasks of social cognition, particularly in the domains of emotion processing, theory of mind, social perception, and attributional style, and these impairments are uniquely associated with poor functional outcome. Researchers have begun to investigate the pattern and magnitude of social cognitive impairment among individuals early in the course of schizophrenia and in people considered to be at elevated risk for psychosis, such as clinical high-risk samples and unaffected relatives of probands. This chapter evaluates the emerging research literature on social cognition in the early phase of schizophrenia. For each of the four social cognitive domains noted above, we provide an overview of common assessment methods and review relevant research comparing first episode/recent-onset schizophrenia patients, clinical high-risk samples (i.e., putatively prodromal), and genetic high-risk (i.e., unaffected relatives) to matched healthy control subjects. Deficits in emotion processing, theory of mind, and social perception are clearly detectable in first-episode/recent-onset patients and are comparable in magnitude to those seen in chronically ill patients. Among clinical high-risk and unaffected relatives, the magnitude of impairment is more variable and, in general, appears to be smaller than impairments seen among those with established illness. Attributional style is the least studied social cognitive domain and consistent patterns have not yet been identified. The implications and limitations of existing studies, and important areas for further research, are discussed.

Stress reactivity of emotional and verbal speech content in schizophrenia.

Abstract Speech fundamental frequencies (SFFs) are nonverbal sound frequencies that convey emotion in speech. The degree of SFF long-term averaged spectra (LTAS) convergence between conversants reflects aspects of conversant-reported quality of the interaction (e.g., emotional synchrony). This study investigated whether SFF LTAS convergence between inpatients diagnosed with schizophrenia (n = 20) and an interviewer was associated with severity of illness (SOI), formal speech disturbance (FSD), and stress reactivity of FSD. Participants provided speech samples describing stressful and nonstressful life experiences. In the stress condition, SFF LTAS was negatively correlated with SOI and FSD. Moreover, patients exhibiting stress reactivity of FSD also evidenced stress reactivity of SFF LTAS. These findings suggest that the emotional and verbal contents of speech are disrupted by stress in schizophrenia, and SOI is associated with FSD and reduced emotional communication during stressful conditions. The interaction between stress reactivity of FSD and SFF LTAS supports the construct validity of a reactivity dimension in schizophrenia.

Hallucinations, neuroplasticity, and prediction errors in schizophrenia

Auditory hallucinations, a hallmark symptom of psychosis, are experienced by most people with a diagnosis of schizophrenia at some point in their illness. Auditory hallucinations can be understood as a failure in predictive coding, whereby abnormalities in sensory/perceptual processing combine with biased cognitive processes to result in a dampening of normal prediction error signaling. In this paper, we used a roving mismatch negativity (MMN) paradigm to optimize evaluation of prediction error signaling and short-term neuroplasticity in 30 people with schizophrenia (n = 16 with and n = 14 without recent auditory hallucinations) and 20 healthy comparison participants. The recent hallucinations group exhibited an abnormal roving MMN profile [F(2,27) = 3.98, p = 0.03], significantly reduced prediction error signaling [t(28) = -2.25, p = 0.03], and a trend for diminished short-term neuroplasticity [t(28) = 1.80, p = 0.08]. There were no statistically significant differences between the healthy comparison group and the combined schizophrenia group on any of the roving MMN indices. These findings are consistent with a predictive coding account of hallucinations in schizophrenia, which posits reduced prediction error signaling in those who are prone to hallucinations. These results also suggest that plasticity-mediated formation and online updating of predictive coding models may also be disrupted in individuals with recent hallucinations.