O:50 Cognitive Deficits, Length of Illness & Symptom Severity in Schizophrenia
K. Eadie∗, G.I. de Zubicaray, S.V. Catts
Department of Psychiatry, University of Queensland, Brisbane, Australia
Background Research using neuropsychological testing has demonstrated that patients with schizophrenia show deficits in multiple neurocognitive domains. The aim of this study is to identify cognitive deficits that correlate with length of illness and symptom severity.
Method Twenty clinically stable outpatients with chronic schizophrenia (18M : 2F) and 14 healthy controls (13M : 1F), matched on age, gender and parental education, were administered a neuropsychological battery consisting of the Hayling Sentence Completion Test (HSCT), WMS-III Verbal Paired Associates & Letter Number Sequencing, Modified Card Sort Test (MCST), Pyramids & Palm Trees Test, National Adult Reading Test (NART), Controlled Oral Word Association Test (COWAT), and WAIS-III. Severity of symptoms was rated with the Structured Clinical Interview – Positive and Negative Syndromes Scale (SCI-PANSS).
Results In comparison to controls, patients showed significant deficits on all of the neuropsychological tasks except for the COWAT. MCST total categories, NART, Verbal IQ and arithmetic, similarities & digit symbol of the WAIS-III had the largest effect size between the groups. The longer the illness duration, the poorer the performance on WAISIII block design and the lower the performance IQ score. The poorer the performance on WMS-III letter number sequencing, the greater the positive symptoms, negative symptoms and general psychopathology.
Conclusion Compared to controls, patients showed large effect sizes on measures of executive functioning, intelligence, working memory, verbal comprehension and speed of processing. The findings suggest that impairment in executive functioning and performance IQ is associated with length of illness, while impairment in working memory is associated with heightened symptom severity.
O:51 Preserved versus compromised intellectual functioning in first-episode psychosis: patterns of cognitive functioning and stability over time
L.K. Byrne∗, A. Redoblado-Hodge, S. Lucase, D. Fitzgerald, J. Brennan
Deakin University, Melbourne, Victoria
Aims/Background The aim of this paper was to examine cognitive profiles in First Episode Psychosis (FEP), based on levels of intellectual functioning at symptom onset. In addition, the stability of neuropsychological functioning over the course of 12 months was explored.
Methods Ninety-one young people (age 13–26) participated in the Western Sydney Early Psychosis Study at Time.1 and 54 were retested 12 months later with a comprehensive neuropsychological battery. Premorbid ability was assessed using the WRAT-3 and current IQ via the WAIS-3 and the WISC-3.
Results Evidence for distinct patterns of cognitive dysfunction in FEP was found. Well over half of our participants (63%) had preserved intellect and correspondingly preserved functioning on a wide range of neuropsychological measures (the Preserved group). A further 26% demonstrated at least a 10 point decline in IQ from their premorbid levels (Deteriorated group). A third group of 11% were found to have compromised intellectual functioning (more than 1 standard deviation below normal) at onset (Compromised group). These latter two groups displayed substantial impairments in neuropsychological functioning including impairments in executive abilities, attention, verbal learning and verbal memory. Patterns of cognitive functioning were relatively stable over time with the Preserved group showing greater improvements than the other two groups.
Conclusions The findings corroborate the hypothesis that there are distinct patterns of neuropsychological impairment in FEP. Furthermore, cognitive deficits that are discernable in FEP are relatively persistent in the short-term. Identifying subgroup patterns early in the course of psychosis may assist in predicting outcomes and drive efforts towards appropriate intervention.
O:52 Personality traits in genetically distinct groups of schizophrenia patients and their relatives
A. Jablensky, J. Badcock, M. Dragovic∗, B. Cloninger
Centre for Clinical Research in Neuropsychiatry, Graylands Hospital/School of Psychiatry and Clinical Neurosciences, University of Western Australia
Background Two homogeneous schizophrenia subtypes, each featuring a specific configuration of neurocognitive performance, neurobehavioral anomalies and selected personality measures, were identified in our previous study (Hallmayer et al., 2005). The first, “Cognitive deficit” (CD) type, comprising patients and a small number of unaffected relatives (n = 76), displayed pervasive deficit on almost all neurocognitive measures. Family members assigned to the remaining types (n = 312) were close to controls on neurocognitive measures but showed significantly deviant scores on temperament and character scales and three dimensions of schizotypy, and were pooled into Non-CD type.
Methods Using canonical correlation analysis we examined whether specific profiles of personality, assessed by the Temperament and Character Inventory (Cloninger et al., 1993) were related to schizotypal dimensions, assessed by the Schizotypal Personality Questionnaire (Raine 1991). Once the relationship was confirmed, we examined its invariance across both groups.
Results Simple mean scores on personality scales and schizotypy factors were generally uninformative, with siblings of schizophrenia patients having virtually identical scores on almost all scales as their parents. However, distinct associations between structure of personality traits (temperament and character) and schizotypal factors emerged in the two schizophrenia subtypes.
Conclusion A simple clinical, primarily negative, symptomatology in CD patients is probably due to reduced cognitive efficiency, whereas dysfunctional cognitive control could be responsible for more prominent positive symptoms in Non-CD patients and their clinically unaffected first degree relatives. This is consistent with Kraepelin's observations that prominent signs of schizophrenia include a lessened ability to produce ideas and concepts and diminished capacity to sift, arrange and correct the existing ones.
O:53 Source Monitoring and Auditory Hallucinations in Clinical and Non-clinical Samples
F. Asgari∗, G. Cumming, J. Farhall
School of Psychological Science, La Trobe University
Background Cognitive models of auditory hallucinations (AHs) in individuals with psychosis propose an inability to adequately distinguish between self-generated mental events and externally-generated events. AHs are therefore experienced when internally generated mental events are misattributed to external sources. However, phenomenological studies show that hallucinators do not always attribute the source of their voices externally: In psychotic disorders, attributions of the origin of a voice may change over time from external (true hallucinations) to internal (pseudohallucinations). Further, the presence of pseudohallucinations in people with no clinical diagnosis raises questions about the applicability of the source monitoring theory. The present study investigates source monitoring in voice-hearers from clinical and non-clinical populations.
Method One hundred and sixty participants completed a source monitoring task, a structured interview focussing on phenomenology and measures of cognitive functioning. Of 80 hallucinators with a diagnosis of schizophrenia, 40 attributed their experiences to the self (true hallucinators), and 40 attributed their voices to non-self origins (pseudohallucinators). A further 80 participants had no psychiatric diagnoses; 40 of these had experienced voices in the past, and 40 had never heard voices in the past.
Results Preliminary results showed that true and pseudo hallucinators did not differ in source monitoring ability; however, there was a significant difference between clinical and non-clinical groups. This difference in source monitoring was not significant when verbal memory and IQ were controlled for.
Conclusions A source monitoring deficit may not be essential for the experience of hallucinations. The higher rate of source monitoring errors in hallucinators may be a reflection of more general impairment in cognitive functioning rather than a specific deficit in monitoring the source of events. Implications for cognitive models of AHs will be discussed.
O:54 Normal and Anomalous Classification of Category Exemplars in Schizophrenia
E.R. Bendall∗, K.L. McMahon, M.M. Eastburn, K. Eadie, G.L. Durbridge, M.W. Strudwick, G. Cowin, G.I. de Zubicaray, S.V. Catts
Centre for Magnetic Resonance, University of Queensland
Background Schizophrenia has been associated with semantic memory impairment and previous studies report a difficulty in accessing semantic category exemplars (Moelter et al. 2005 Schizophr Res 78:209–217). The anterior temporal cortex (ATC) has been implicated in the representation of semantic knowledge (Rogers et al. 2004 Psychol Rev 111(1):205–235). We conducted a high-field (4T) fMRI study with the Category Judgment and Substitution Task (CJAST), an analogue of the Hayling test. We hypothesised that differential activation of the temporal lobe would be observed in schizophrenia patients versus controls.
Methods Eight schizophrenia patients (7M : 1F) and eight matched controls performed the CJAST, involving a randomised series of 55 common nouns (from five semantic categories) across three conditions: semantic categorisation, anomalous categorisation and word reading. High-resolution 3D T1-weighted images and GE EPI with BOLD contrast and sparse temporal sampling were acquired on a 4T Bruker MedSpec system. Image processing and analyses were performed with SPM2.
Results Differential activation in the left ATC was found for anomalous categorisation relative to category judgment, in patients versus controls.
Conclusions We examined semantic memory deficits in schizophrenia using a novel fMRI task. Since the ATC corresponds to an area involved in accessing abstract semantic representations (Moelter et al. 2005), these results suggest schizophrenia patients utilise the same neural network as healthy controls, however it is compromised in the patients and the different ATC activity might be attributable to weakening of category-to-category associations.
O:55 Cognitive mechanisms of depression in schizophrenia
F. Waters∗1,2,3, J. Badcock2,3, M. Maybery1
1School of Psychology and 2School of Psychiatry and Clinical Neurosciences, University of Western Australia, 3Centre for Clinical Research in Neuropsychiatry, Graylands Hospital, Perth
Background Depression is a frequent feature of schizophrenia, but the cognitive processes that characterise depressive symptoms in schizophrenia are still unclear. Recent studies of clinical depression have shown faulty inhibitory mechanisms of selective attention for negative information. The current study examined whether patients with schizophrenia also show selective attention towards negative information.
Methods Forty-three patients with schizophrenia and 24 healthy controls completed the Affective Shifting Task (Murphy et al., 1999), in which participants are required to respond to target words of one valence (positive or negative adjectives), while inhibiting responses to words of the alternate affective category.
Results As a group, schizophrenia patients did not show an attentional bias for negative material. However, those patients with high levels of depression demonstrated faster latencies when negative words were the targets. In addition, higher depression scores were associated with an increasing number of false alarms on negative words when they were not the targets.
Conclusion Schizophrenia patients with a depressed mood show distortions in information processing characterised by selective attention for negative information. This cognitive bias may contribute to the development and maintenance of depression.
O:56 The SRM as an Explanatory Model in Schizophrenia
K. Menon∗, T. Bhattacharya
Department of Humanities & Social Sciences Indian Institute of Technology, Powai, Mumbai, India
Explicit models such as the Self-Regulation Model (SRM), (Leventhal, Nerenz, & Steele, 1984) have been shown to be useful in highlighting key beliefs across a wide range of different physical and mental illnesses. Causal models of illness are an important component of what Kleinman (1980) has called ‘explanatory models’ – the notions that people have about the classification, causes, course and appropriate management of an episode of illness. These beliefs profoundly affect emotional & behavioral responses, care-seeking behavior, outcome of illness, and adherence to recommended interventions. Illness beliefs have been associated with a variety of outcomes, including Expressed Emotion (EE) levels in caregivers. This paper attempts to examine the association between illness beliefs and EE levels in primary caregivers of patients with Schizophrenia, using the SRM framework. Patient symptomatology and caregiver-patient relationship were examined in this context. Internal causal attributions and negative illness labeling were found to be associated with higher EE levels. Low symptom chronicity as observed in Paranoid symptom Schizophrenia is associated with higher EE, negative labeling and perception of negative illness consequences. Developing psychological theories common to both physical and mental health may eventually result in an integrated approach to mental illness, thereby fostering favorable prognosis.
