Kouzou Takeuchi

Reduction in hippocampal formation volume is caused mainly by its shortening in chronic schizophrenia: Assessment by MRI

We performed contiguous, 1 mm thick, magnetic resonance imaging scans in 18 men with chronic schizophrenia and in 18 age-matched healthy subjects to test in living patients the findings of a previous postmortem study. The schizophrenic patients showed bilaterally shortening (left, -6%; right, -9%) and volume reduction (left, -9%; right, -11%) of the hippocampal formation (HF). Volumes of HF correlated positively with HF length in the schizophrenic patients. The reduction in bilateral HF volumes was small after controlling for HF lengths (left, -3%; right, -3%). In schizophrenic patients, significant negative correlations were found bilaterally between the length of HFs and the scores for attention, bizarre behavior, and positive formal thought disorder. The results suggest that the volume reduction seen in the HFs of schizophrenic patients was caused mainly by a shortening of the HF and that these clinical symptoms may be associated with shorter HF length.

Phosphorus magnetic resonance spectroscopy in schizophrenia: Correlation between membrane phospholipid metabolism in the temporal lobe and positive symptoms

1. To determine any correlations between phosphorus metabolites in the temporal lobes and clinical symptoms in schizophrenic patients, the authors performed 31phosphorus magnetic resonance spectroscopy in 31 medicated patients and age- and sex- matched normal subjects. 2. Schizophrenic patients demonstrated an increased level of phosphodiesters (PDE) in the temporal lobes bilaterally and a decreased level of beta-adenosine triphosphate (beta-ATP) in the left temporal lobe. 3. A significant positive correlation was observed between the level of PDE in the left temporal lobe and the score of positive symptoms on the Brief Psychiatric Rating Scale. 4. These results suggest that altered membrane phospholipid metabolism in the left temporal lobe is associated with neuroleptic-resistant positive symptoms in schizophrenic patients.

Changes in glucose metabolism due to aging and gender-related differences in the healthy human brain.

Using [(18)F]fluoro-deoxy-glucose-PET, we studied relative metabolic changes due to age- and gender-related differences in the brain of 126 healthy subjects from their twenties to seventies. We used a data-extraction technique, the three-dimensional stereotactic surface projections (3D-SSP) method, to measure metabolic changes with fewer effects of regional anatomic variances. Simple regression analysis revealed significant age-related increases in relative metabolic values in the parahippocampal and amygdala regions in both sexes in their twenties to forties, and significant age-related decreases in both sexes in their fifties to seventies. Relative values in the frontal lobe showed significant age-related decreases in both sexes in their twenties to forties, but these effects were not seen in subjects in their fifties to seventies. Significant gender differences in correlation coefficients of relative values with age were shown in the parahippocampal, primary sensorimotor, temporal, thalamus and vermis regions in subjects in their 20s to 40s, but disappeared in subjects in their twenties to forties, but were not apparent in subjects in their fifties to seventies except in the vermis. Males in their twenties to sixties and females in their fifties showed significant laterality in relative values in the temporal lobes. Our study demonstrated age- and gender-related differences in glucose metabolism in healthy subjects.

Correlation of third ventricular enlargement and EEG slow wave activity in schizophrenic patients

Twenty-eight schizophrenic patients and 22 normal control subjects underwent magnetic resonance imaging (MRI) and topographic electroencephalography (EEG) in a study attempting to correlate morphological and electrophysiological findings. Schizophrenic patients had larger anterior horns of the lateral ventricles and third ventricles than normal control subjects. Schizophrenic patients showed more delta wave activity in the right parietooccipital region than normal control subjects. Alpha 2 wave activity was reduced in the entire region in schizophrenic patients. In schizophrenic patients, a significant positive correlation was seen between the area of the third ventricle and delta wave activity in the right occipital region. These results suggest that schizophrenic patients may have a dysfunction of diencephalic structures associated with morphological abnormality.

31P magnetic resonance spectroscopy of the medial temporal lobe of schizophrenic patients with neuroleptic-resistant marked positive symptoms

Abstract31P magnetic resonance spectroscopy was performed in 16 medicated schizophrenic patients with neuroleptic-resistant marked positive symptoms and in 16 healthy volunteers matched for age and sex in order to determine what changes in phosphorus metabolites are detected in such patients as compared to the controls. The schizophrenic patients showed an increased level of phosphodiesters in the bilateral medial temporal lobes. They also showed a decrease in the level of β-ATP in the left medial temporal lobe. These findings suggest that schizophrenic patients with prominent positive symptoms refractory to neuroleptics may have a disturbance of bilateral membrane phospholipid and left-sided high-energy phosphate metabolism in the medial temporal lobe.

Argyria and convulsive seizures caused by ingestion of silver in a patient with schizophrenia

Abstract The case study of a schizophrenic patient with argyria which resulted from the chronic and excessive ingestion of antismoking pills contain silver, is presented. Convulsive seizures developed after the patient had been addicted to the pills for 40 years. An extremely high concentration of silver was detected in serum. This case provides support for the hypothesis that silver may cause convulsive seizures as a result of systemic poisoning.

Metabolic changes in the brain of patients with late-onset major depression

Positron emission tomography (PET) with fluorodeoxyglucose-F18 was used to examine glucose metabolism in patients with late-onset major depression, all hospitalized non-responders to antidepressant medication. The three-dimensional stereotactic surface projection (3D-SSP) method provided 3D-SSP images and relative metabolic values with minimal partial volume effects. The 3D-SSP score map showed decreased relative metabolism in the prefontal, cingulate and parietal regions in both hemispheres, and in the temporal region on the right, and increased relative metabolism in the occipital pole, vermis, cerebellum, dorsal-frontal, central convexity areas and basal ganglia in both hemispheres in patients compared with controls. The ratio of the parietal to occipital values in right plus left hemispheres was significantly decreased. Correlation coefficients of the anterior cingulate-primary sensorimotor, posterior cingulate-primary sensorimotor and occipital-media frontal in both hemispheres, of the frontal-primary sensorimotor, occipital-parahippocampal, primary visual-medial frontal and parahippocampal-amygdala in the right, and the frontal-vermis, parietal-thalamus, temporal-vermis, occipital-putamen, primary visual-putamen, thalamus-vermis and thalamus-cerebellum in the left were significantly different in patients compared with controls. Patients with late-onset depression who were treatment non-responders showed alterations not only in limbic-cortical circuits, but also in a wider network of thalamo-cortical circuits.

Dysfunctional Cortical Connectivity During the Auditory Oddball Task in Patients with Schizophrenia

Background: We studied the imaginary coherence (IC) of gamma frequency oscillations between brain regions of male schizophrenia patients during an auditory oddball task using magnetoencephalography (MEG) and electroencephalography (EEG). Methods: Subjects were 10 right-handed male schizophrenia patients, evaluated by the positive and negative symptom scale (PANSS), and 10 healthy controls. Functional connectivity during the auditory oddball task was reconstructed in low (30-50 Hz) and high (50-100 Hz) gamma bands, and represented by imaginary coherence (IC) based on significant oscillatory power changes. We calculated correlations between PANSS scores and IC. Results: In the high gamma band, IC between left occipital and right prefrontal lobe areas during the time window 750-1000 ms from stimulus onset showed negative correlations with total negative scores, total positive scores, the sum of positive and negative scores in PANSS, conceptual disorganization, and social avoidance scores. In the low gamma band, IC between the same areas from 250-500 ms also showed a negative correlation with the conceptual disorganization score. In the same time window, IC between left occipital and right frontoparietal lobe areas in the low gamma band showed a positive correlation with hallucinatory behavior; IC between right temporal pole and left prefrontal lobe areas showed a positive correlation with delusion scores, although these ICs were decreased relative to controls. Conclusions: Functional disconnection of high and low gamma bands in auditory oddball task may play an important role in the auditory processing in schizophrenia patients.

Changes in Event-Related Desynchronization and Synchronization during the Auditory Oddball Task in Schizophrenia Patients

Objective: We studied differences in the spatiotemporal dynamics of cortical oscillation across brain regions of patients with schizophrenia and normal subjects during the auditory oddball task using magnetoencephalography (MEG) and electroencephalography (EEG). Methods: Ten right-handed male schizophrenia patients were studied. We used a newly developed adaptive spatial filtering algorithm optimized for robust source time-frequency reconstruction of MEG and EEG data, and obtained consecutive images in functional maps of event-related desynchronization (ERD) and synchronization (ERS) in theta, lower alpha (8–10 Hz), upper alpha (10–13 Hz), and beta bands. Results: Beta ERD power at 750–1000 ms in patients was significantly increased in large right upper temporal and parietal regions and small upper portions of bilateral dorsal frontal and dorsal-medial parietal regions. Theta ERS power in schizophrenic patients during the oddball task was significantly increased in the left temporal pole at 250–500 ms, and was significantly increased in dorsal, medial frontal, and anterior portions of the anterior cingulate cortex in both hemispheres, and the left portion of lateral temporal regions at 500–750 ms, compared to the control group (family-wise error correction p<0.05). Lower alpha ERS power was significantly decreased in the right occipital region at 500–750 ms and in the right midline parietal and bilateral occipital regions at 750–1000 ms. Upper alpha ERS power was significantly decreased in right midline parietal and left occipital regions at 750–1000 ms. Conclusions: ERD/ERS changes were noted in the left temporal pole and midline frontal and anterior cingulate cortex in theta ERS, occipital lobe in alpha ERS, and right temporal-frontal-parietal, midline frontal, and anterior cingulate cortex in beta ERD. These findings may reflect disturbances in interaction among active large neuronal groups and their communication with each other that may be related to abnormal cognitive and psychopathological function. Significance: Study of ERD and ERS by time-frequency analyses using MEG is useful to clarify data processing dysfunction in schizophrenia.

Shortening of the hippocampal formation in first‐episode schizophrenic patients

Abstract Shortening of hippocampal formation (HF) in chronic schizophrenic patients have been demonstrated in our previous study. The purpose of the present study is to test if shortening of the HF occurs in schizophrenic patients suffering their initial psychotic episode. We performed contiguous, 1 mm thick, magnetic resonance imaging scans in 20 first‐episode schizophrenic patients, 21 chronic schizophrenic patients, and 25 healthy subjects. Both groups of schizophrenic patients demonstrated significant shortening of the HF compared with normal controls (first‐episode schizophrenia, 5.3%; chronic schizophrenia, 8.0%). However, the HF length was not significantly different between the first‐episode and chronic schizophrenic patients. No significant correlation was seen between the HF length and the duration of illness in chronic schizophrenic patients. These results suggest that the HF shortening observed in schizophrenic patients may be genetic and/or developmental in origin.