Intellectual Functioning as an Endophenotype for Schizophrenia

  • Odette de Wilde

Abstract

Different studies have shown that abnormal cognitive functioning is present in patients with schizophrenia even in the early phase of the disease. Cognitive deficits in patients with schizophrenia are characterised by a generalised intellectual deficit, coupled with abnormalities in specific neuropsychological domains such as working memory, attention and executive functioning.

Intellectual deficits have been suggested to precede psychosis in patients with schizophrenia and also to be a risk factor for developing schizophrenia. If the presence of intellectual deficits would coincide with increased risk to develop schizophrenia they should be present in excess of general population levels in the biological relatives of individuals with schizophrenia.

Studies investigating intellectual functioning in first-degree relatives of patients with schizophrenia indeed have shown deficits in intellectual functioning paralleling the degree of genetic liability in that performance of the relatives fell between the performance of the patients and the controls.

In this chapter recent results in literature investigating the evidence, that a generalized intellectual deficit coupled with deficits in specific domains is also present in first-degree relatives of patients with schizophrenia, is reviewed and discussed in the light of its usefulness in identifying schizophrenia susceptibility genes.

Keywords

Schizophrenia endophenotype intelligence 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Odette de Wilde
    • 1
  1. 1.Department of PsychiatryAcademic Medical Center, University of AmsterdamThe Netherlands

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