Neuropsychological Mechanism of Delusion

Lee, S H; Kim, D W; Park, Y Z; Park, H J; Shin, Y S

Abstract

OBJECTIVES
The Psychopathology of schizophrenia was expected to be related with? focal dysfunction of brain while schizophrenia is recognized and studied as the brain disease. Authors studied correlation between neuropsychological tests and delusion which is representative symptom of schizophrenia in patients with head trauma and psychiatric patients in order to explore the functional localization of brain in delusional symptom.
METHODS
Halstead Reitan Neuropsychological Test Battery and Korean Weschler Intelligent Scale and Minnesota Multipbasic Personality Inventory (MMPI) were administered to one hundred nineteen patients consisted of sixty nine psychiatric patients and fifty patients with brain damage. We tested correlation between results of neuropsychological tests and delusional scale made from twenty four items related with delusion in MMPI. T-test between eighteen higher delusion scorers and twenty one lower scorers was examed in psychiatric group.
RESULTS
In brain damage group, signigicant correlations were found in the tests related with function of frontal lobe such as category test, trail making AB test, tactual performance test, digit symbol test and fingertip number writing test, and significant correlations were also noted in the tests related with function of left temporal and parietal lobes such as information, comprehension, vocabulary, similarities and speech sound perception test. The tests related with the function of right hemisphere such as tactual performance test location, picture completion and performance, and the tests related with subcortical function such as arithmetic, digit span, attention, digit symbol test, digit symbol and trail making AB test were significantly corelated with delusional scale too. In psychiatric group there were significant difference of delusional score in the tests related with subcortical function of left hemisphere such as vocabulary, vocable IQ, comprehension and language, and in the tests related with subcortical function such as N120 voltage, digit symbol and arithmetic.
CONCLUSIONS
Delusion seems to be related with function of frontal lobe, left hemisphere and subcortex in both groups. Right hemisphere may be also partially related with delusion.