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Accumulating evidence suggests that schizophrenic patients do not use context efficiently. Also, studies suggest similarities in clinical and cognitive profiles between schizophrenic and schizotypal personality disorder (SPD) individuals, and epidemiological studies point to a genetic link between the two disorders. This study examined electrophysiological correlates of processing sentence context in a group of SPD women in a classical N400 sentence paradigm. The study assessed if the dysfunction in context use found previously in schizophrenia and male SPD also exists in female SPD. We tested 17 SPD and 16 matched normal control women. The results suggest the presence of abnormality in context use in female SPD similar to that previously reported for male schizophrenic and SPD individuals, but of lesser degree of severity. In SPD women, relative to their comparison group, a more negative N400 was found only to auditory congruent sentences. DescriptorsSentence processing; Schizotypal personality disorder women; Context; Event-related potentials; Language; N400 Language dysfunction in schizophrenia is regarded as one of the primary features of this disease. Speech in schizophrenic patients is often characterized by loose and bizarre associations, lack of coherence, and inability to maintain a theme. It has been recently proposed that these features of schizophrenic speech are the result of dysfunction in semantic memory operations. The two processes suggested to be abnormal are the activation in semantic memory networks (Manschreck et al

A right ear advantage in healthy adults for perceiving consonant-vowels was associated with a left-lateralized ERP component peaking at 200 milliseconds after syllable onset (N2). Patients with schizophrenia failed to show either of these task-dependent asymmetries, which may indicate a dysfunction of left temporal regions involved in phonetic classification. A task-independent asymmetric reduction of a later positive potential in patients with schizophrenia resembled left temporal P3 reductions reported for auditory oddball tasks.

The findings support the hypotheses that undifferentiated schizophrenia is associated with underactivation of left hemisphere resources for verbal processing and that paranoid schizophrenia is characterized by preserved left hemisphere processing.

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