Dong Woo Lee

Neural correlates of clinical symptoms and cognitive dysfunctions in obsessive-compulsive disorder.

Although results from neuropsychological and neuroimaging studies have postulated the involvement of the frontal lobe and the subcortical brain regions in the pathophysiology of obsessive-compulsive disorder (OCD), neuroimaging studies have provided little evidence that cognitive abnormalities in patients with OCD are related to dysfunctions in these areas. This study was designed to determine whether the clinical features and cognitive deficits of OCD might be taken to reflect frontal-subcortical dysfunction. Fourteen patients with OCD and 14 case-matched normal subjects completed clinical and cognitive evaluation, including four sets of neuropsychological tests that assessed the executive functions and visual memory. Cerebral glucose metabolic rates were measured by using positron emission tomography (PET) with 18F-fluorodeoxyglucose. Behavioral and PET data were analyzed using statistical parametric mapping for group differences and behavioral-metabolic correlates. The right orbitofrontal cortex showed increased metabolic activity and the left parieto-occipital junction showed decreased metabolic activity in patients. Metabolism in the right hippocampus, the left putamen and the right parietal region was associated with the severity of obsessive-compulsive symptoms. Correlations between metabolic rates and neuropsychological test scores in the prefrontal cortex and the putamen occurred only in the patient group. These results suggest that patients with OCD have distinct features of brain metabolic activities for performing cognitive tasks as well as presenting obsessive-compulsive symptoms. In particular, the frontal-subcortical circuits might mediate not only symptomatic expression but also cognitive expression in patients with OCD.

Brain single photon emission computed tomography findings in depressive pseudodementia patients

BACKGROUNDnRecently, there have been studies suggesting that depressive pseudodementia would include early-stage dementing disorder. Through the comparison of the 99mTc-HMPAO single photon emission computed tomography (SPECT) image of depressive pseudodementia subjects, healthy comparison subjects, depressed subjects free of cognitive impairment, and dementia of Alzheimers type (DAT) subjects, we aimed to see part of pathophysiology of the depressive pseudodementia of elderly patients.nnnMETHODSnStudy subjects consisted of seven patients with depressive pseudodementia, seven healthy comparison subjects, seven patients with depression free of cognitive impairment, and eleven patients with DAT. Depression patients were diagnosed according to DSM-III-R. DAT patients were diagnosed by DSM III-R and NINCDS-ADRDA criteria of DAT. Other measures for assessment include Hamilton Rating Scale for Depression and Mini Mental State Exam. All underwent 99mTc-HMPAO SPECT scan. The images of each group were analyzed using statistical parametric mapping of Friston, which compares the images on voxel-by-voxel basis.nnnRESULTSnThe results were as follows (1) The DAT group showed significant decreases of cerebral blood flow (CBF) in the right frontal, right temporal region, and both parietal regions as compared with control group (P < 0.05). (2) The depression group showed a significant decrease of CBF in the left frontal region as compared with control group (P < 0.05). (3) The depressive pseudodementia group showed significant decreases of CBF in both parietal regions as compared with control group (P < 0.05). (4) The depressive pseudodementia group showed significant decreases of CBF in the right temporal region and both parietal regions as compared with depression group (P < 0.05). (5) The DAT group showed significant decreases of CBF in the right temporal region, both frontal regions, and both parietal regions as compared with depressive pseudodementia group (P < 0.05).nnnLIMITATIONSnThe small number of subjects may make it difficult to generalize from our results. Because decreased CBF in depressive pseudodementia is found while the subjects were depressed, we cannot tell whether it is a state marker or a trait marker.nnnCONCLUSIONSnThe depressive pseudodementia group showed decreased CBF in the temporo-parietal region, similar to that of the DAT group and different from that of the depression group.

ASSOCIATIONS BETWEEN SUBJECTIVE MEMORY COMPLAINTS AND EXECUTIVE FUNCTIONS IN A COMMUNITY SAMPLE OF ELDERLY WITHOUT COGNITIVE DYSFUNCTION

P3-535 ASSOCIATIONS BETWEEN SUBJECTIVE MEMORY COMPLAINTS AND EXECUTIVE FUNCTIONS IN A COMMUNITY SAMPLE OF ELDERLY WITHOUT COGNITIVE DYSFUNCTION Jae-Nam Bae, Won-Hyoung Kim, Byung-Soo Kim, Sung-Man Chang, Dong Woo Lee, Maeng-Je Cho, Inha University Hospital, Incheon, Republic of South Korea; Kyungpook National University Hosptial, Daegu, Republic of South Korea; Inje University College of Medicine, Seoul, Republic of South Korea; Seoul National University Hospital, Seoul, Republic of South Korea. Contact e-mail: jnbae@inha.ac.kr