incentive motivation in first episode psychosis
TRANSCRIPT
Presenting Author details: [email protected]. 21, 3007 Bern, Switzerland,Tel.: +41 31 6328811; fax: +41 31 6328944.
Background: Sustained attention is discussed as a core deficit inschizophrenia and as a candidate endophenotype. Various neuropsy-chological tasks are thought to measure sustained attention; one ofthem is the Rapid Visual Information Processing Task (RVIP).Previous studies in schizophrenia patients showed that these patientshave severe problems in performing this task. The aim of the presentstudy was to investigate whether healthy first-degree relatives ofschizophrenia patients show reduced sustained attentional perfor-mance as measured by the RVIP.
Methods: A sample of 23 healthy first-degree relatives of schizo-phrenia patients and 88 controls participated in this study. They allperformed the RVIP, on which three target sequences had to bedetected. Hits and reaction time were recorded during RVIPperformance for each subject. The sensitivity index A′ was derivedfrom these data.
Results: The ANCOVA revealed that the relatives were significantlyless sensitive (A′) at detecting target sequences than the controls,pb .004. The result is corrected by possible age or educationinfluences.
Conclusions: The result supports the assumption that sustainedattention, as measured with a difficult RVIP version, could be apossible endophenotype in schizophrenia. However, it is assumed thatthis result is also influenced by working memory and perceptualdiscrimination processes, as these components are additionallyinvolved in the RVIP.
Acknowledgement: Financial support was provided by the BerneUniversity Research Foundation.
doi:10.1016/j.schres.2007.12.045
INCENTIVE MOTIVATION IN FIRST EPISODE PSYCHOSIS
G.K. Murray 1,2,3, L. Clark2, P.R. Corlett1,2, A.D. Blackwell1,R. Cools2, P.B. Jones1,2,3, T.W. Robbins1,2, L. Poustka4.
1Brain Mapping Unit, Department of Psychiatry, CambridgeUniversity, United Kingdom2Cambridge University Behavioural and Clinical NeuroscienceInstitute, United Kingdom3CAMEO Early Psychosis Service, Cambridge, United Kingdom4Zentralinstitut für Seelische Gesundheit, Mannheim, Germany
Presenting Author details: [email protected] of Psychiatry, Experimental Psychology, Downing Street,CB2 3EB Cambridge, United Kingdom,Tel.: +44 1223764676; fax: +44 1223764675.
Background: It has been proposed that there are abnormalities inincentive motivational processing in psychosis, possibly secondary tosubcortical dopamine abnormalities, but few empirical studies haveaddressed this issue.
Methods: We studied incentive motivation in 18 first episodepsychosis patients from the Cambridge early psychosis service(CAMEO) and 19 control participants using the Cued Reinforcement
Reaction Time Test, which measures motivationally driven behavior.We also gathered information on participants' attentional, executiveand spatial working memory function in order to determine whetherany incentive motivation deficits were secondary to generalizedcognitive impairment. After 12 months, patients were assigneddiagnoses based on all available information and the performance ofschizophrenia patients was compared with that of bipolar patients.
Results: We demonstrated the anticipated reinforcement relatedspeeding effect in controls (17 out of 19 control participantsresponded faster during an “odd-one-out” task in response to a cuethat indicated a high likelihood of a large points reward). Only 4 outof 18 patients showed this effect and there was a significantinteraction effect between Reinforcement Probability and Diagnosison Reaction Time (F1,35=14.2, p=0.001). This deficit was presentin spite of preserved executive and attentional function in patientsand persisted even in antipsychotic medication free patients. Therewas no difference between schizophrenia and bipolar disorder inperformance.
Conclusions: There are incentive motivation processing abnormalitiesin first episode psychosis; these may be secondary to dopaminedysfunction and are not attributable to generalized cognitiveimpairment.
Acknowledgement: Funding from a UK Department of HealthResearch Capacity Development award to Dr Murray.
doi:10.1016/j.schres.2007.12.046
WHAT DO PATIENTS WITH SCHIZOPHRENIA KNOW WHENTHEY CANNOT REMEMBER?
E. Bacon 1, M. Izaute2.
1INSERM U 666, Strabourg, France2LAPSCO, University, Clermont-Ferrand, France
Presenting Author details: [email protected] U 666, Clinique Psychiatrique, Hopital Civil BP 426, 67091Strasbourg Cedex, France,Tel.: +33 3 88 11 64 60; fax: +33 3 88 11 64 46.
Background: Even when people fail to recall a solicited memorytarget, they can provide Feeling Of Knowing judgments (FOK) thatreflect the ability to predict the future retrievability of the item.According to the accessibility model of metamemory (Koriat 1993,1995), FOK rating does not rely on the target answer, but it monitorsthe accessibility of partial and/or contextual information about theunrecognized target, irrespective of their accuracy. FOK validity atpredicting memory performance relies on the accuracy of that set ofrelated information. There are some evidences that the FOKsexpressed by patients with schizophrenia differ from the controlsratings, but that their predictive validity towards a future retrieval ispreserved (Bacon et al., 2001, 2007). Also the accessibility modelproved to be valid in patients following a learning session of simpleinformation (Bacon and Izaute, 2007).
Methods: To further understand the cognitive and metacognitivebehaviour of patients, the accessibility model was investigated for longterm knowledge in a task assessing semantic memory. The taskconsisted of general information questions and was adapted fromKoriat (1995). In case of recall errors, participants were asked to
23ABSTRACTS / Schizophrenia Research 98 (2008) 3–199