Kategorisierung und Arbeitsgedächtnis bei schizophrenen Patienten : eine kontrollierte PET-Studie

This study researched schizophrenic patients compared to healthy control subjects regarding their neuropsychological performances in categorization and working memory tasks. The according brain activity was measured by PET. We were led by two hypotheses: 1. Schizophrenic patients make more mistakes in classing items with certain categories 2. Schizophrenic patients show abnormal activity within the left temporal lobe.For activation we used the Strooptest v1.0 by S. Erberich, IZKF Aachen, and the working memory task taken from the TAP Software by Zimmermann and Fimm (1994). Our findings in in the working memory task indicate a discretely diminished activity within the right dorsolateral prefrontal cortex in schizophrenic patients. Further, we found a diminished activity within the cerebellum and the right thalamus in schizophrenic patients. This supports Andreasens (1998) theory of "cognitive dysmetria" in schizophrenic patients. Additional differences in activation could be found within the temporal lobes of both sides and the Cingulum. Apart from that, hippocampal and basal ganglia (caudate nucleus and claustrum) were activated differently. Both in the working memory and in the categorization tasks the schizophrenic patients did not make significantly more mistakes than the control subjects. Their correct-positive reaction times were significantly slower in both tasks, though. Activation patterns demonstrated by schizophrenic patients and healthy controls in medial and lateral temporal structures were different when working on categorization tasks. Only the healthy controls activated the the right fusiform gyrus temporally. Further, only the schizophrenic patients activated limbic structures on both sides. This indicates that our second hypothesis is correct. With only slightly worse neuropsychological performances, the schizophrenic patients activated larger areas of the left medial temporal lobe. This indicates that our second hypothesis is correct. The schizophrenic patients did not demonstrate more false-positive reactions in the categorization task than the healthy healthy controls. This either indicates that our first hypothesis is wrong or that the degree of difficulty of the task was too low to provoke significantly more false-positive reactions.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2004

Author dc:creator

• Brinkmann, Frank

Contributors dc:contributor

• Erkwoh, Ralf

• info:eu-repo/classification/ddc/610
• Medizin
• Kategorisierung
• Arbeitsgedächtnis
• PET
• Schizophrenie
• funktionelle Hirnbildgebung

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123631%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:62033