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Most schizophrenia research is undertaken on clinical samples in current contact with mental health services. It is not clear to what extent such samples are representative of the population of people with schizophrenia or whether they differ significantly, for example, from those who are being treated predominantly in primary care settings or who are recruited from non-clinical sources. Data from a volunteer schizophrenia research register and two recent Australian studies are reported, the Low Prevalence (psychotic) Disorders Study and an associated study of schizophrenia in general practice, in which all participants completed the same clinical assessment interview. Participants meeting criteria for schizophrenia or schizoaffective disorder were classified according to their source of recruitment: volunteer research register (n=128), general practice (n=123), community (n=236) or public inpatient (n=178) mental health services. Hierarchical discriminant function analyses revealed significant differences between these recruitment sources with respect to illness-onset factors, relationship and support factors, current functioning and course of illness. A severity/functioning gradient was observed across the four recruitment sources, possibly reflecting a spectrum of neurobiological impairment from good to poor prognosis. The implications of these findings for sampling strategies in schizophrenia research are discussed. [Copyright &y& Elsevier]

We used a psychophysiological marker of visual attention (the visual scanpath) to investigate the effects of atypical (risperidone) vs. typical (haloperidol) antipsychotic medication on facial emotion perception in schizophrenia (n=28) and healthy control (n=28) groups. Of the schizophrenia subjects, 15 were prescribed risperidone. Visual scanpaths to ‘happy’, ‘sad’ and ‘neutral’ faces were recorded using video-oculography, and concurrent emotion-recognition accuracy was assessed using multiple-option tasks. Compared to control subjects, both schizophrenia subgroups showed a restriction in visual scanning (reduced total fixation number and decreased scanpath length). Haloperidol-treated schizophrenia subjects exhibited an additional and consistent pattern of reduced attention (fixation) to salient features for neutral and happy. By contrast, risperidone-treated subjects showed a relatively greater attention to salient features for these expressions, in which they did not differ from controls. Recognition accuracy for happy and neutral showed a similar lack of impairment. These findings suggest that risperidone may play a specific role in schizophrenia in the ability to attend to salient features, and to integrate this information into an accurate percept for neutral and positive expressions in particular. [Copyright &y& Elsevier]

Background: Abnormal visual scanpaths to faces and facial expressions in schizophrenia may underlie schizophrenic subjects’ disturbed interpersonal communication. This study is the first to examine the specificity of these impairments to schizophrenia, by including an affective disorder psychiatric control group.Methods: The visual scanpath performance of 65 schizophrenia, 52 affective disordered, and 61 control subjects were compared in two experiments. In the “face recognition” experiment, subjects viewed four identifiable (non-degraded) neutral faces versus four matched non-identifiable (degraded) control faces. In the “facial affect recognition” experiment, subjects viewed positive (happy), negative (sad), and neutral (control) facial emotion stimuli. Concurrent behavioral tasks were face matching (face recognition) and expression matching (facial affect recognition), each under two multiple-choice conditions (7 or 3 options).Results: Scanpath disturbances were most apparent in schizophrenia subjects, who maintained a comparatively “restricted” scanpath style to all face stimuli. Schizophrenics subjects also showed the greatest recognition difficulties, particularly for neutral and happy faces. Scanpath parameters for affective disorder subjects differed only from the schizophrenia (but not the control) group, except for attention to facial features where they generally avoided facial features in all expressions and showed the greatest attentional problems of all groups for degraded faces.Conclusions: Our results suggest that a global restriction of visual scanpaths is specific to schizophrenic psychosis and might be a trait marker for this disorder, whereas scanpath abnormalities in affective disorder might instead reflect severe state-based (or discrete) attentional disturbances. [ABSTRACT FROM AUTHOR]

Abstract: People with 22q11.2 deletion syndrome (22q11DS) have deficits in face emotion recognition. However, it is not known whether this is a deficit specific to faces, or represents maladaptive information processing strategies to complex stimuli in general. This study examined the specificity of face emotion processing deficits in 22q11DS by exploring recognition accuracy and visual scanpath performance to a Faces task compared to a Weather Scene task. Seventeen adolescents with 22q11DS (11=females, age=17.4) and 18 healthy controls (11=females, age=17.7) participated in the study. People with 22q11DS displayed an overall impoverished scanning strategy to face and weather stimuli alike, resulting in poorer accuracy across all stimuli for the 22q11DS participants compared to controls. While the control subjects altered their information processing in response to faces, a similar change was not present in the 22q11DS group indicating different visual scanpath strategies to identify category within each of the tasks, of which faces appear to represent a particularly difficult subcategory. To conclude, while this study indicates that people with 22q11DS have a general visual processing deficit, the lack of strategic change between tasks suggest that the 22q11DS group did not adapt to the change in stimuli content as well as the controls, indicative of cognitive inflexibility rather than a face specific deficit. [Copyright &y& Elsevier]

Abstract: Childhood adversity is associated with elevated risk for a wide range of adult psychiatric disorders, and has significant and sustained negative effects on adult behavioural and social functioning. Elevated rates of childhood adversity have been reported for people with a diagnosis of schizophrenia. The aim of the present study was to assess rates of retrospectively reported childhood adversity among adults with schizophrenia and to examine the relationship between childhood adversity and clinical and cognitive features. Data were available for 408 schizophrenia participants and 267 healthy control participants recruited through the Australian Schizophrenia Research Bank (ASRB). History of childhood adversity was obtained using the Childhood Adversity Questionnaire (CAQ). A five-factor solution was identified from the CAQ. Schizophrenia participants reported experiencing more childhood adversities than controls. In both groups, those reporting childhood adversity were more likely to be female and older. Among participants with schizophrenia, positive symptom severity and fewer years of education were associated with childhood adversity. Lower IQ scores and personality traits were associated with reporting a greater number of childhood adversities and with adversity sub-types of abusive, neglectful and dysfunctional parenting. The rate of childhood adversity reported in this sample was high which suggests greater exposure to adverse childhood events among participants with schizophrenia in comparison with healthy controls. We identified unique groups amongst CAQ items that provided a salient framework from which to investigate the connection between childhood adversity and clinical and cognitive features. [Copyright &y& Elsevier]

Abstract: Relationships between substance use, severity of psychosis, and neuropsychological functioning were examined, together with their associations with treatment response and retention status. Participants included 477 people with psychosis (354 volunteers registered on a research database, and 123 enrolled in a treatment trial for substance misuse). Variables of primary interest included substance use history, course of psychotic disorder, and neuropsychological functioning on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Specific RBANS deficits were associated with a more chronic illness course. Compared to those with a stable or chronic course, younger people with a single episode of psychosis were more likely to have uncertain diagnoses, higher levels of substance use problems and variable neuropsychological functioning. History of substance use was not associated with additional overall neuropsychological deficits. Likewise, treatment retention and outcome were not associated with neuropsychological functioning. The findings suggest that, among people with co-existing psychotic and substance use disorders, response to cognitive-behaviour therapy is likely to be independent of neuropsychological functioning. Consideration should also be given to the potential use of neuropsychological assessments to assist differentiation of likely substance-associated psychosis from primary psychosis. [Copyright &y& Elsevier]

Abstract: Previous research demonstrates that people with 22q11.2 deletion syndrome (22q11DS) have social and interpersonal skill deficits. However, the basis of this deficit is unknown. This study examined, for the first time, how people with 22q11DS process emotional face stimuli using visual scanpath technology. The visual scanpaths of 17 adolescents and age/gender matched healthy controls were recorded while they viewed face images depicting one of seven basic emotions (happy, sad, surprised, angry, fear, disgust and neutral). Recognition accuracy was measured concurrently. People with 22q11DS differed significantly from controls, displaying visual scanpath patterns that were characterised by fewer fixations and a shorter scanpath length. The 22q11DS group also spent significantly more time gazing at the mouth region and significantly less time looking at eye regions of the faces. Recognition accuracy was correspondingly impaired, with 22q11DS subjects displaying particular deficits for fear and disgust. These findings suggest that 22q11DS is associated with a maladaptive visual information processing strategy that may underlie affect recognition accuracy and social functioning deficits in this group. [Copyright &y& Elsevier]