Diane C. Gooding

Clinical Status of At-Risk Individuals 5 Years Later: Further Validation of the Psychometric High-Risk Strategy.

The authors hypothesized that at-risk individuals identified on the basis of their Chapman scale scores would be diagnosed with schizophrenia-spectrum disorders at follow-up. In the present study, the authors interviewed 135 young adults approximately 5 years following their initial assessment. The at-risk groups included high scorers on the Perceptual Aberration and/or Magical Ideation Scales (n=59) and high scorers on the revised Social Anhedonia Scale (n=32). The control participants (n=44) scored below 0.5 SD of the same-sex group means on all the scales. At the follow-up, the groups differed in terms of their likelihood of having a schizophrenia-spectrum diagnosis, Chi2(2)=9.79, p<.01. The at-risk groups reported more frequent and severe psychotic-like experiences relative to the control group. These findings support the predictive validity of the Chapman psychosis-proneness scales and may enhance the power of early detection efforts.

Wisconsin Card Sorting Test deficits in schizotypic individuals.

The present study investigates executive functioning in schizotypic college students and control subjects using the Wisconsin Card Sorting Test (WCST). Inhibitory control and working memory, two aspects of executive functioning, were examined in deviantly high scorers on the Perceptual Aberration and Magical Ideation Scales (n=97), high scorers on the revised Social Anhedonia Scale (n=58), and in control subjects (n=104). The schizotypic groups displayed significantly more perseverative errors and achieved fewer categories than the control group. The two schizotypic groups did not differ from each other. We identified a subset of schizotypic individuals who also produced clinically deviant WCST profiles. The findings support the hypothesis that executive function deficits may precede the onset of schizophrenia and related illnesses.

Working memory and Wisconsin Card Sorting Test performance in schizotypic individuals : a replication and extension

The present study examined spatial working memory and Wisconsin Card Sorting Test (WCST) performance in psychosis-prone individuals, either those with extremely high scores on the Social Anhedonia Scale (SocAnh; n = 49) or deviant scores on the Perceptual Aberration-Magical Ideation Scales (Per-Mag; n = 66). Sixty-three individuals with normal scores on the Chapman Psychosis-Proneness Scales served as control subjects. In order to evaluate working memory performance, participants were administered three tasks, namely, sensorimotor, degraded stimulus, and delayed-response tasks. Although the SocAnh and Per-Mag groups displayed poorer performance than control subjects on the working memory task, they did not differ significantly from each other. The SocAnh group exhibited slower reaction times on the working memory task compared to the control group. The groups did not differ in their performance on sensorimotor or degraded stimulus control tasks. Both psychosis-prone groups differed significantly from control subjects in terms of their WCST performance. Working memory performance was inversely associated with the number of perseverative errors (r = -0.17) and the number of trials to complete the first category on the WCST (r= -0.15). These findings extend the literature by indicating that some psychosis-prone individuals with social-interpersonal schizotypal deficits also display subtle spatial working memory impairments.

Spatial, object, and affective working memory in social anhedonia: an exploratory study

The domain-specificity of working memory was examined in psychosis-prone individuals with elevated social anhedonia scores. A group of individuals with deviant scores on the revised Social Anhedonia Scale (n=43) were compared with a normal control group (n=39) on delayed match-to-sample tasks involving spatial, identity, and affective information. The social anhedonia group performed less well on the spatial and emotion delayed match-to-sample tasks relative to the normally hedonic group. The two groups did not differ in terms of their performance on the identity delayed match-to-sample task. Although the social anhedonia group reported less positive affect, greater negative affect, and more alexithymic tendencies relative to the control group, there were no significant associations between these personality traits and working memory performance. In summary, the findings suggest that poorer working memory performance is not domain-specific in socially anhedonic individuals. The authors conclude that the socially anhedonic groups relatively poor performance on the emotion delayed match-to-sample task reflects difficulty and/or inefficiency in handling cognitively taxing tasks.

Cognition and Brain Function in Schizotypy: A Selective Review

Schizotypy refers to a set of personality traits thought to reflect the subclinical expression of the signs and symptoms of schizophrenia. Here, we review the cognitive and brain functional profile associated with high questionnaire scores in schizotypy. We discuss empirical evidence from the domains of perception, attention, memory, imagery and representation, language, and motor control. Perceptual deficits occur early and across various modalities. While the neural mechanisms underlying visual impairments may be linked to magnocellular dysfunction, further effects may be seen downstream in higher cognitive functions. Cognitive deficits are observed in inhibitory control, selective and sustained attention, incidental learning, and memory. In concordance with the cognitive nature of many of the aberrations of schizotypy, higher levels of schizotypy are associated with enhanced vividness and better performance on tasks of mental rotation. Language deficits seem most pronounced in higher-level processes. Finally, higher levels of schizotypy are associated with reduced performance on oculomotor tasks, resembling the impairments seen in schizophrenia. Some of these deficits are accompanied by reduced brain activation, akin to the pattern of hypoactivations in schizophrenia spectrum individuals. We conclude that schizotypy is a construct with apparent phenomenological overlap with schizophrenia and stable interindividual differences that covary with performance on a wide range of perceptual, cognitive, and motor tasks known to be impaired in schizophrenia. The importance of these findings lies not only in providing a fine-grained neurocognitive characterization of a personality constellation known to be associated with real-life impairments, but also in generating hypotheses concerning the aetiology of schizophrenia.

Eye Tracking Dysfunction in Schizophrenia: Characterization and Pathophysiology

Eye tracking dysfunction (ETD) is one of the most widely replicated behavioral deficits in schizophrenia and is over-represented in clinically unaffected first-degree relatives of schizophrenia patients. Here, we provide an overview of research relevant to the characterization and pathophysiology of this impairment. Deficits are most robust in the maintenance phase of pursuit, particularly during the tracking of predictable target movement. Impairments are also found in pursuit initiation and correlate with performance on tests of motion processing, implicating early sensory processing of motion signals. Taken together, the evidence suggests that ETD involves higher-order structures, including the frontal eye fields, which adjust the gain of the pursuit response to visual and anticipated target movement, as well as early parts of the pursuit pathway, including motion areas (the middle temporal area and the adjacent medial superior temporal area). Broader application of localizing behavioral paradigms in patient and family studies would be advantageous for refining the eye tracking phenotype for genetic studies.

Antisaccade task performance in questionnaire-identified schizotypes

Individuals who scored high on Perceptual Aberration-Magical Ideation Scales (Per-Mag; n = 90), the Social Anhedonia Scale (SocAnh; n = 39), and control participants (n = 89) were administered saccadic refixation (prosaccade) and saccadic suppression (antisaccade) tasks. Eye movements were scored in terms of error rates and latency. None of the groups differed in terms of their performance on the prosaccade task. Both the Per-Mag (p < 0.01) and SocAnh (p < 0.05) groups exceeded the controls in terms of mean antisaccade errors. The high-risk groups did not differ from each other. Eighteen of the Per-Mag individuals and 10 of the SocAnh individuals displayed deviant antisaccade performance. These findings are particularly interesting in light of suggestive evidence that antisaccade task deficits may serve as a marker of susceptibility to schizophrenia. It is hypothesized that the individuals who scored aberrantly on the Chapman scales and displayed antisaccade performance deficits are most likely to be at risk for the development of psychosis.

Spatial working memory performance in patients with schizoaffective psychosis versus schizophrenia: a tale of two disorders?

We explored the relationship between schizophrenia and schizoaffective disorder by comparing the two patient groups in terms of their performance on measures of executive functioning (spatial working memory and Wisconsin Card Sorting Test). Patients with schizophrenia (N=34) and those with schizoaffective disorder (N=23) performed significantly poorer than community controls (N=30). However, the schizoaffective and schizophrenia groups did not differ from each other in terms of working memory accuracy or mean response latencies. Similarly, the two patient groups did not differ in terms of the number of categories achieved or number of perseverative errors on the Wisconsin Card Sorting Test. Among the patients, working memory accuracy was associated with number of WCST perseverative errors and number of categories achieved, though working memory performance was not associated with number of WCST nonperseverative errors. These findings indicate that both schizophrenia and schizoaffective disorder are associated with executive functioning deficits. The findings are discussed in the context of the ongoing debate regarding the conceptualization of schizoaffective disorder.

Smooth pursuit eye tracking and visual fixation in psychosis-prone individuals

Subjects identified by Perceptual Aberration-Magical Ideation (Per-Mag) scores (n=97), Social Anhedonia (SocAnh) scores (n=45), and Physical Anhedonia (PhysAnh) scores (n=31) as well as normal controls (n=94), underwent psychophysiological and clinical assessment. This is the first published investigation of pursuit system functioning in three groups of questionnaire-identified at-risk individuals. Pursuit during a simple non-monitor tracking task was measured using root-mean-square error (RMSE) scores and pursuit gain scores. Fixation performance was measured in terms of number of saccades away from the central fixation point. The at-risk subjects were more likely to display aberrant smooth pursuit tracking than controls, though there were no significant differences between the at-risk subjects endorsing items relevant to positive-symptom schizotypy and those endorsing items pertaining to negative-symptom schizotypy. The groups did not differ significantly in their visual fixation performance. Participants were also evaluated for the presence of Axis I symptomatology and psychotic-like experiences. Neither the experimental subjects nor the control subjects displayed a significant association between ocular motor performance and psychotic-like experiences. These findings are consistent with prior evidence that pursuit tracking is a trait characteristic, independent of clinical status.

Normative emotion-modulated startle response in individuals at risk for schizophrenia-spectrum disorders

The nature of the affective deficit that characterizes social anhedonia is not well understood. Emotionally evocative visual stimuli were presented to undergraduates identified as anhedonic or normal, based on their scores on the revised Social Anhedonia Scale. The affective stimuli were chosen to elicit positive and negative emotion; a subset of slides were specifically chosen to include social-interpersonal content. In the acoustic startle paradigm, participants were administered startle probes (50-ms 95 dB white noise bursts) while viewing images from the International Affective Picture System. Socially anhedonic individuals did not differ from normally hedonic individuals in terms of their physiological response to the stimuli, regardless of the nature of the content of the stimuli. However, on the self-report measures of trait affectivity, the socially anhedonic individuals reported significantly lower levels of positive affect and higher levels of negative affect. These findings suggest that the affective deficits reported by socially anhedonic individuals are not global in nature.