Silvia Corbera

Social Cognitive Impairments and Negative Symptoms in Schizophrenia: Are There Subtypes With Distinct Functional Correlates?

Social cognitive impairments and negative symptoms are core features of schizophrenia closely associated with impaired community functioning. However, little is known about whether these are independent dimensions of illness and if so, whether individuals with schizophrenia can be meaningfully classified based on these dimensions (SANS) and potentially differentially treated. Five social cognitive measures plus Scale for the Assessment of Negative Symptoms (SANS) and Positive and Negative Syndrome Scale (PANSS) scores in a sample of 77 outpatients produced 2 distinct factors--a social cognitive factor and a negative symptom factor. Factor scores were used in a cluster analysis, which yielded 3 well-defined groupings--a high negative symptom group (HN) and 2 low negative symptom groups, 1 with higher social cognition (HSC) and 1 with low social cognition (LSC). To make these findings more practicable for research and clinical settings, a rule of thumb for categorizing using only the Mayer-Salovey-Caruso Emotional Intelligence Test and PANSS negative component was created and produced 84.4% agreement with the original cluster groups. An additional 63 subjects were added to cross validate the rule of thumb. When samples were combined (N = 140), the HSC group had significantly better quality of life and Global Assessment of Functioning (GAF) scores, higher rates of marriage and more hospitalizations. The LSC group had worse criminal and substance abuse histories. With 2 common assessment instruments, people with schizophrenia can be classified into 3 subgroups that have different barriers to community integration and could potentially benefit from different treatments.

Factor Structure of Social Cognition in Schizophrenia: Is Empathy Preserved?

Social cognitive impairments are core features of schizophrenia and are closely associated with poor functional outcome. This study sought to identify specific aspects of social cognition and their relationships to measures of social function, quality of life, and neurocognition. Principal component analysis was performed using social cognitive measures in patients with schizophrenia and healthy matched controls and revealed three factors: Interpersonal Discomfort, Basic Social Cognition, and Empathy. Patients had higher scores on Interpersonal Discomfort and lower scores on Basic Social Cognition than controls, but the two groups were the same on Empathy. Lower social performance was significantly correlated with poor Basic Social Cognition in patients and with high Interpersonal Discomfort in controls. While neurocognition was significantly associated with Basic Social Cognition in both groups, it was not associated with Empathy. Social cognitive interventions should emphasize improving basic social cognitive processing deficits, managing Interpersonal Discomfort, and utilizing preserved capacity for empathy as a potential strength in social interactions.

Social skills training and computer-assisted cognitive remediation in schizophrenia

A growing body of research shows that cognitive remediation (COG REM), consisting of drill-and-practice and/or strategy training in neurocognitive functions, produces moderate improvements in neurocognition. These improvements generalize to functioning when COG REM is provided with other rehabilitation interventions (Wykes et al., 2011). The number of studies using COG REM as an adjunct to other behavioral-based rehabilitation interventions however remains small and consists of widely varying interventions with few active control conditions. This study compared the effects of an extended (6-month), standardized, computer-assisted cognitive remediation intervention, administered along with a standardized program of social skills-training (SST), with those of an active control condition that included participation in the same SST program and a computer skills training program (Computer Skills). Sixty-four individuals with schizophrenia recruited from two treatment sites were randomly assigned to one of two conditions and were assessed by blinded raters on neurocognitive measures, performance-based measures of social skill, and ratings of psychosocial function before and after treatment. Results revealed that the COG REM group improved significantly more in attention, working memory, and empathy than the Computer Skills group, but there were no differences between groups on other measures of psychosocial functioning or skills. Taken together, these findings suggest that COG REM used in the context of other evidence-based psychosocial interventions (SST) improves working memory in schizophrenia and suggests that this effect may generalize to improved empathy.

Successful computer-based visual training specifically predicts visual memory enhancement over verbal memory improvement in schizophrenia

We investigated whether improved early visual processing on cognitive remediation (CR) exercises generalizes to visual and auditory learning and information manipulation in schizophrenia. Fourteen participants received neuropsychological testing before and after CR consisting of visual, auditory and cognitive control training. Achievement on visual training exercises was strongly and significantly correlated with improved visual learning, but not improved verbal learning or increased ability to manipulate visual information. Improvement in training, not training time, predicted cognitive gain. Implications for improving cognitive outcomes from CR include ensuring the trained task is learned and providing exercises of multiple modalities.

Emotion self-regulation and empathy depend upon longer stimulus exposure

Observation of others in pain induces positive elevation (pain effect) in late event-related potentials (ERP). This effect is associated with top-down attention regulating processes. It has previously been shown that stimulus exposure duration can affect top-down attentional modulation of response to threat-related stimuli. We investigated the effect of exposure duration on ERP response to others in pain. Two late ERP components, P3 and late positive potentials (LPP), from 18 healthy people were measured while they viewed pictures of hands in painful or neutral situations for either 200 or 500 ms, during two task conditions (pain judgment and counting hands). P3 and LPP pain effects during the pain judgment condition were significantly greater with 500 ms than 200 ms stimulus presentation. Ours is the first study to suggest that engagement of empathy-related self-regulatory processes reflected in late potentials requires longer exposure to the pain-related stimulus. Although this is important information about the relationship between early sensory and subsequent brain processing, and about engagement of self-regulatory processes, the neural basis of this time-dependence remains unclear. It might be important to investigate the relationship between stimulus duration and empathic response in clinical populations where issues of self-regulation, empathic response and speed of information processing exist.

Neural activation abnormalities during self-referential processing in schizophrenia: An fMRI study

Impairments in self-awareness contribute to disability in schizophrenia. Studies have revealed activation abnormalities in schizophrenia in cortical midline structures associated with self-reference. We used functional magnetic resonance imaging to compare activation throughout the brain in people with schizophrenia and healthy controls (Kelly et al., 2002) while they indicated whether trait adjectives described attributes of themselves, their mother or a former president of the United States. Blood oxygenation level dependent signal in each condition was compared to resting fixation. Patients were less likely and slower to endorse positive self-attributes, and more likely and quicker to endorse negative self-attributes than controls. Activation abnormalities reported previously in cortical midline structures were again noted. In addition, patients showed greater signal increases in frontal, temporal gyri and insula, and smaller signal decreases in posterior regions than healthy controls when thinking about themselves. Group differences were less evident when subjects were thinking about their mothers and tended to go in the opposite direction when thinking about a president. Many of the areas showing abnormality have been shown in other studies to differ between patients and controls in structure and with other activation paradigms. We suggest that general neuropathology in schizophrenia alters the neural system configurations associated with self-representation.

Cognitive remediation for adults with schizophrenia: Does age matter?

Cognitive remediation (CR), a novel behavioral intervention designed to improve cognitive deficits through repeated task practice and/or strategy acquisition has gained increasing empirical support in people with schizophrenia, but substantial individual differences in treatment response remain (Wykes et al., 2011). The role of age on response to CR in schizophrenia remains understudied. We evaluated the role of three age ranges in treatment response to CR relative to a closely-matched computer skills control intervention in a blinded, randomized control trial (RCT) with 112 adults with schizophrenia divided into three groups: an early-stage group (ES; 25 years or younger, mean=3.4 years of illness; n=45), an early-chronic group (EC; 26-39, mean=7.6 years of illness; n=31) and a late-chronic group (LC; 40 and over, mean=18.2 years of illness; n=36). With respect to cognitive outcomes, early-stage and early-chronic individuals with schizophrenia showed greater improvement in response to CR on a working memory measure at a trend level, relative to late-chronic clients. These findings were confirmed in analyses of a subsample of clients who received an adequate dose of treatment. These findings emphasize the need for adaptations of currently-existing CR programs to more effectively address the needs of older client populations.

Physiological evidence of a deficit to enhance the empathic response in schizophrenia

Empathy is crucial for maintaining effective social interactions. Research has identified both an early-emotional sharing and a late-cognitive component of empathy. Although considered a functionally vital social cognition process, empathy has scarcely been studied in schizophrenia (SZ). We used event-related potentials (ERPs) to study the temporal dynamics of empathic response in 19 patients with SZ and 18 matched healthy controls (HC) using an empathy for physical pain paradigm. Participants responded to pictures of hands in neutral and painful situations in an active empathic condition and one manipulated by task demands. Additionally, subjective ratings of the stimuli and empathic self-reports were collected. People with SZ had (1) decreased early-emotional ERP responses to pictures of others in pain; (2) decreased modulation by attention of late-cognitive ERP responses; (3) lower ratings of perspective taking and higher ratings of personal distress which were both related to decreased modulation of late-cognitive empathic responses; (4) a significant relationship between high affective overlap between somebody elses pain and their own pain and decreased modulation of late-cognitive empathic responses; (5) a distinct relationship between regulatory deficits in late-cognitive empathy and functioning. Patients had present but reduced early and late empathy-related ERPs. Patients also reported increased personal distress when faced with distress in others. The late ERP responses are thought to be associated with self-regulation and response modulation. The magnitude of these late responses was inversely associated with reported levels of personal distress in both patients and controls. Additionally, regulatory deficits in cognitive empathy were highly related with deficits in functioning. Decreased ability to regulate ones own emotional engagement and response to emotions of others may be an important source of distress and dysfunction in social situations for patients with schizophrenia.

Increasing stimulus duration can normalize late-positive event related potentials in people with schizophrenia: Possible implications for understanding cognitive deficits

This study determined whether increasing stimulus duration for patients with schizophrenia normalized late Event Related Potentials (ERPs) associated with modulation of response to emotion-evoking stimuli. These ERPs are decreased in patients versus healthy controls when both view stimuli of the same duration. Subjects viewed pictures of hands and judged whether the events depicted were painful or non-painful. Pictures were presented to patients for 500 or 800 ms and to healthy controls for 200 or 500 ms. Participants were 19 adult outpatients meeting DSM-IV criteria for schizophrenia or schizoaffective disorder and 18 healthy controls, as assessed by the Structured Clinical Interview. ERPs to neutral stimuli during a 350-900 ms window following stimulus onset were subtracted from ERPs during this same response window to pain stimuli. The area under this difference wave reflected the degree of pain-related positivity and was the dependent measure for analysis. Patient late-positive ERP responses following 500 and 800 ms stimuli were highly similar to responses in healthy controls following 200 and 500 ms stimuli respectively. Patients and controls differed significantly when responses to 500 ms stimuli were compared. People with schizophrenia are known to process information more slowly than healthy people. Our results indicate that slowed early processing of sensory input may limit engagement of higher cognitive and regulatory processes in patients with schizophrenia. This may be one reason that self-regulation is compromised in patients, and may help explain why measures of slowed information processing account for so much variance in other cognitive deficits in schizophrenia.

Measuring theory of mind in schizophrenia research: Cross-cultural validation

Theory of mind (ToM) is the ability to understand mental states of others and it is crucial for building sensitivity to other persons or events. Measuring ToM is important for understanding and rehabilitating social cognitive impairments in persons with schizophrenia. The Social Attribution Task-Multiple Choice (SAT-MC) has been successfully employed to measure ToM between individuals with schizophrenia (SZ) and healthy controls (HC) in North America. Given that the SAT-MC uses geometric shapes, is nonverbal and less culturally loaded than other social cognition measures, it may serve for measuring ToM in schizophrenia across cultures. A total of 120 participants (30 per group; Korean SZ; Korean HC; North American SZ; North American HC) were selected from existing databases to examine the reliability and validity of the SAT-MC. Internal consistency, factor structure, measurement invariance, discriminant validity, and convergent/divergent validity were examined. The SAT-MC had good internal consistency regardless of the clinical and cultural group as evidence by Cronbachs α ≥ 0.78 in all groups. Confirmatory factor analysis confirmed the one-factor model with a good model fit (χ2 = 188.122, TLI = 0.958, CFI = 0.963, RMSEA = 0.045). The SAT-MC was sensitive to detect individual differences in ToM of SZ and HC, regardless of culture (p < 0.001), and significantly correlated with other social cognition tasks (Hinting and Reading the Mind in the Eyes Test) among Korean and North American patients. The SAT-MC is a reliable measure for evaluating ToM in both Koreans and North Americans with or without schizophrenia, supporting its potential utility in diverse language and cultures for schizophrenia research.