Hostname: page-component-8448b6f56d-c4f8m Total loading time: 0 Render date: 2024-04-17T06:24:25.017Z Has data issue: false hasContentIssue false

Event-related potentials elicited during a context-free homograph task in normal versus schizophrenic subjects

Published online by Cambridge University Press:  01 July 2000

DEAN F. SALISBURY
Affiliation:
Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA McLean Hospital, Belmont, Massachusetts, USA Brockton Veterans Affairs Medical Center, Brockton, Massachusetts, USA
BRIAN F. O'DONNELL
Affiliation:
Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA Brockton Veterans Affairs Medical Center, Brockton, Massachusetts, USA
ROBERT W. McCARLEY
Affiliation:
Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA McLean Hospital, Belmont, Massachusetts, USA Brockton Veterans Affairs Medical Center, Brockton, Massachusetts, USA
PAUL G. NESTOR
Affiliation:
Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA Brockton Veterans Affairs Medical Center, Brockton, Massachusetts, USA
MARTHA E. SHENTON
Affiliation:
Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA McLean Hospital, Belmont, Massachusetts, USA Brockton Veterans Affairs Medical Center, Brockton, Massachusetts, USA
Get access

Abstract

Thought disorder in schizophrenia may involve abnormal semantic activation or faulty working memory maintenance. Event-related potentials (ERPs) were recorded while sentences reading “THE NOUN WAS ADJECTIVE/VERB” were presented to 34 schizophrenic and 34 control subjects. Some nouns were homographs with dominant and subordinate meanings. Their sentence ending presented information crucial for interpretation (e.g., The bank was [closed, steep]). Greatest N400 activity to subordinate homograph-meaning sentence endings in schizophrenia would reflect a semantic bias to strong associates. N400 to all endings would reflect faulty verbal working memory maintenance. Schizophrenic subjects showed N400 activity to all endings, suggesting problems in contextual maintenance independent of content, but slightly greater N400 activity to subordinate endings that correlated with the severity of psychosis. Future research should help determine whether a semantic activation bias in schizophrenia toward strong associates is reflected in ERP activity or whether this effect is overshadowed by faulty verbal working memory maintenance of context.

Type
Research Article
Copyright
2000 Society for Psychophysiological Research

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)