This proposal represents a maturation of my interest in schizophrenic thought disorder, and my commitment to a multidisciplinary approach to its study. The program I describe here will provide me with fundamental skills in psycholinguistics and cognitive psychology which are directly relevant to research on schizophrenia, and which have not yet been applied in this field. Schizophrenics' use of language has been characterized as lacking in contextual constraint. Psycholinguists distinguish between various loci of contextual effects in language processing, identifying a lexical stage (access to a word's meaning) and postlexical stages. Maher has described a failure to actively suppress contextually irrelevant associations in schizophrenia, and attributes this to a deficit in postlexical processing. I have proposed an alternative, non-competing hypothesis which suggests that disturbances may also arise within lexical processing which account for similar results. In Phase I of this program, I will develop a parallel distributed computer model of language processing. Variables will be sought which can be manipulated in actual psycholinguistic experiments, and which distinguish between the effects of stimulus persistence and postlexical events on the processing of context. In Phase II, I will perform experiments with normal and schizophrenic subjects using chronometric lexical priming techniques, to test predictions which arise from these computer simulations. Positive findings in patients will be correlated with clinical variables, in order to explore the use of these techniques for diagnostic assessment. Work in Phases I and II will be directed to the testing of specific hypotheses concerning schizophrenic language dysfunction. This will not only allow me to explore the functional characteristics of thought disorder, but will also provide me with a training in theoretical and methodological techniques which will be of general value in psychiatric research.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Physician Scientist Award (K11)
Project #
5K11MH000673-05
Application #
3087957
Study Section
Research Scientist Development Review Committee (MHK)
Project Start
1987-02-01
Project End
1992-01-31
Budget Start
1991-02-01
Budget End
1992-01-31
Support Year
5
Fiscal Year
1991
Total Cost
Indirect Cost
Name
Stanford University
Department
Type
Schools of Medicine
DUNS #
800771545
City
Stanford
State
CA
Country
United States
Zip Code
94305
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