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This study registered consecutive cases to elucidate the efficacy of rTMS treatment for depression within the Japanese public health insurance system. Of the 102 patients with depression who received rTMS over the left dorsolateral prefrontal cortex, 44 (43.1 %) patients reached remission and 14 (13.7 %) patients did not reach remission but responded to treatment. No serious adverse events occurred. Low baseline HAMD-17 score was associated with remission after rTMS treatment. Favorable outcomes of rTMS treatment were shown in this cohort within the Japanese public insurance system. Our results provide insights into rTMS treatment for depression in real-world clinical setting., Competing Interests: Declaration of Competing Interest Authors Imazu, Ikeda, Shinosaki, and Takahashi have received speaker honoraria from Teijin Pharma Limited. Author Kanazawa has received materials supervision fee from Teijin Pharma Limited., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Competing Interests: Declaration of Competing Interest Shinichi Yamada, Shun Takahashi, Yuji Ohoshi, Takuya Ishida, Tomikimi Tsuji, Kazuhiro Shinosaki, Masaki Terada, Satoshi Ukai declare that there are no conflicts of interest related to the study.

Although diffusion tensor imaging (DTI) have revealed brain abnormalities in bipolar disorder (BD) subjects, DTI methods might not detect disease-related abnormalities in the white matter (WM) where nerve fibers are crossing. We investigated BD myelin-related abnormal brain regions in both gray matter and WM for 29 BD and 33 healthy control (HC) participants using T1-weighted (T1w)/T2-weighted (T2w) ratio images that increase myelin-related contrast irrespective of nerve fiber orientation. To check effect of the brain volume, the results were compared with those of voxel-based morphometry (VBM). We found significantly lower T1w/T2w signal intensity in broad WM regions in BD subjects, including the corpus callosum, corona radiata, internal capsule, middle cerebellar peduncle and cerebellum. Regional volume reduction was found in the WM bilateral posterior thalami and retrolenticular part of the internal capsules of BD subjects. We also performed tract-based spatial statistics (TBSS) in 25 BD and 24 HC participants and compared those for the T1w/T2w ratio images. Both methods detected the BD corpus callosum abnormality. Further, the ratio images detected the corona radiata and the cerebellar abnormality in BD. These results suggest that T1w/T2w ratio image analysis could take a complementary role with the DTI method in elucidating myelin-related abnormalities in BD., (Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.)

Leigh syndrome is a mitochondrial disease characterized by subacute necrotizing encephalomyelopathy. Almost all cases of Leigh syndrome develop at infancy or early childhood and die within several years due to rapidly progressive muscle weakness and respiratory failure. Here, we present a rare case of a patient who developed Leigh syndrome associated with thiamine-responsive pyruvate dehydrogenase-complex deficiency at 2 years of age and has survived to adolescence through effective high dose thiamin therapy. At 15 years of age, the patient presented persecutory delusions and auditory hallucinations, suggesting an association between mitochondrial dysfunction and schizophrenia-like psychotic symptoms., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In a search for the physiological correlates of mental activity, localized EEG desynchronization induced by mental arithmetic was assessed by the entropy of the EEG power spectrum (irregularity index II). The topographic mapping of II can show a localized cortical activation. Directional EEG patterns during mental arithmetic were further examined with a directed mutual information measure (information flow). These two information measures were compared between resting and mental arithmetic conditions in 10 right-handed subjects as well as one left-handed subject. II significantly increased during mental arithmetic in the left temporo-centro-parietal region in right-handed subjects, thus exhibiting its activation. Significant changes in information flow during mental arithmetic were found in the directions mostly from the temporo-centro-parietal region to other areas and within the frontal region in right-handed subjects: information flow from the left temporal and the mid-frontal areas increased and information flow mostly from the left hemisphere decreased. One left-handed subject showed greater II in right post-temporal area. These findings suggest that the left temporo-centro-parietal activation is specific to calculation processing, and the frontal information flow is related to the active performance of mental arithmetic.

Interhemispheric responses of alpha activity were investigated by use of half-field sinusoidally modulated light (SML) stimulation at the subject's alpha frequency. The left and right visual half-fields as well as full-field were separately stimulated by the SML. The power spectrum of SML responses, averaged with Wiener filtering, was obtained at the left and the right occipital area (O1 and O2) in 11 normal subjects. Power in each hemisphere, phase difference and coherence between O1 and O2 were estimated at an alpha frequency. A laterality index of power was defined as (P(l)-P(r))/(P(l) + P(r)) where P(l) is a power value at O1, and P(r) at O2. In most of the subjects, laterality index decreased in the order: left half-field, full-field and right half-field stimulation. This relationship revealed greater SML responses on the ipsilateral occipital area. There were significant differences in laterality index among 3 visual field conditions, thus showing that full-field responses ranged in lateralization between the left and right half-field responses in most of the subjects. This hemispheric distribution suggests that half-field SML stimulation affected alpha activity selectively in each hemisphere, mostly in the ipsilateral hemisphere.

Relationships between epileptiform discharges and background activity were examined by power spectral entropy (PSE), measuring a degree of EEG irregularity. The EEGs were recorded from 10 electrodes placed at F3, F4, C3, C4, T3, T4, P3, P4, O1 and O2 in 11 epileptic patients with widespread lateralized spike and wave complexes (SWCs). Bipolar records were also made from the antero-posterior derivations. The locations of the maximum PSE coincided with those of the maximum amplitude of SWC in most of the patients. Bipolar derivations with the maximum PSE always included the locations with the maximum PSE obtained from a linked ears reference. Pearson's correlation coefficient between PSE and SWC amplitude was 0.62 +/- 0.14 (mean +/- S.D.) in 11 patients, thus indicating that the scalp distribution of PSE was closely related to that of the amplitude of SWC. These findings suggest that the background EEG is disorganized in or near the epileptogenic focus. A focal background abnormality can therefore be estimated by PSE.

A new method for quantifying irregularity of EEGs is proposed in this study. The entropy, an information measure, determines the uniformity of proportion distribution. The peakedness or flatness of the distribution of the EEG power spectrum, representing EEG rhythmicity, can be measured by the entropy, because the power spectrum consists of proportions of power at each frequency. The irregularity of the EEG was measured by the entropy of the power spectrum, called an irregularity index (II). The II was obtained from the power spectrum at F3, F4, C3, C4, P3, P4, O1 and O2 during rest and mental arithmetic in 10 normal subjects. Relative band powers of delta, theta, alpha and beta bands and alpha peak frequency were also obtained. EEGs during rest were significantly more irregular anteriorly than in the occipital areas. Alpha activity was also more irregular in the anterior region. A greater degree of EEG desynchronization during mental arithmetic was found over the left hemisphere and the right occipital area. The II was more sensitive to such desynchronization than alpha band power and alpha peak frequency. The differences in spectral structures between rest and mental arithmetic conditions, mainly over the left hemisphere, were also confirmed by the Kullback-Leibler information.

Ten epileptic patients who had absence and tonic-clonic seizures were examined. They showed almost generalized 2-5 Hz spike and wave complexes (SWCs) with maxima at the frontal or central locations. Their EEGs were recorded from F3, F4, C3, C4, P3, P4, O1 and O2. One 15 sec EEG epoch, which included the background activity followed by SWCs, was divided into 20 segments. On the basis of Akaike's information criterion obtained from an AR model fitted to each segment by the least squares method, a distance measure between segments was obtained. The 20 segments were classified according to the distance measure with the combined use of both cluster analysis and multidimensional scaling. The power spectrum was also obtained for each segment. There were 2-6 clusters at some locations, always including the largest amplitude locations of the SWCs (the frontal or central locations). The clusters could be grouped into 3 major types, each forming a period: (1) one large cluster distant from the SWCs (the period of background activity); (2) small clusters just before the SWCs (the period just before the SWCs); (3) small clusters during the SWCs (the period of the SWCs). The period just before the SWCs, which occurred earliest at the largest amplitude location, may be a transition state of the background activity to the SWCs. A few segments remote from the SWCs belonged to the small cluster just before or during the SWCs in some patients, thus suggesting that an EEG event similar to EEG changes just before or during the SWCs occurred. The EEG event buried within the background can be considered as a poorly developed epileptiform discharge. A gradual increase or decrease in alpha frequency before the SWCs was found in most patients; this suggests that changes in the level of vigilance occur before SWCs.

Hemispheric specialization for the linguistic process was studied by the 'entropy analysis' method which distinguishes the direction of information flow for mutually coupled time series. Meaningful and non-meaningful stimuli were presented to 14 subjects. EEGs were recorded from homologous Wernicke's and occipital areas in the two hemispheres. The amount of information flow both from the left to right hemisphere and from the right to left hemisphere was obtained under the 3 conditions (i.e., meaningful, non-meaningful and resting baseline conditions) in each area. The information flow from the left to right hemisphere was significantly larger under the meaningful condition than from the right to left hemisphere in Wernicke's area, but no significant differences in the information flow could be found between the two directions under the non-meaningful condition in Wernicke's or the occipital area. Therefore, the dominant direction of the left to right hemisphere was observed under the meaningful condition in Wernicke's area but not in the occipital (non-speech) area, while no dominant direction was observed under the two control (i.e., non-meaningful and baseline) conditions in either area. These results may suggest that the dominant direction of information flow with the meaningful stimuli is related to linguistic meaningfulness in Wernicke's area.

The direction of spread of alpha activity over the scalp was studied using the modified 'entropy analysis' method which distinguishes the direction of time differences between two correlated signals in the alpha band. The resting EEG was recorded from F3, F4, C3, C4, P3, P4, O1 and O2, each referenced to linked ears in 10 subjects. The directed measure of correlation of alpha activity in two directions (e.g., from O1 and O2 and from O2 to O1) was obtained from all possible pairs of electrodes. The dominant longitudinal direction of alpha activity was found to be anterior to posterior within as well as across hemispheres. No dominant transverse direction was found. This suggests that the spread of alpha activity over the scalp is in the dominant anterior-posterior direction.

Source determination of alpha activity was studied using the relative power contribution analysis (RPCA) method which allows determination of the relative contributions of different areas to the power of a certain area at different frequencies. In 20 normal subjects, EEGs were recorded from F3, F4, C3, C4, P3, P4, O1 and O2, each referenced to a linked ear. An 8-dimensional autoregressive model was fitted to the EEGs of 10.24 sec. Based on the model, RPCA was performed. For each area, alpha activity was divided into two parts: one originating in its own area (endogenous) and another in the other areas (exogenous). Endogenous alpha activity increased as the area was more posterior. In the anterior regions (frontal and central), endogenous alpha power (power of endogenous alpha activity) was small, while exogenous alpha power was large. In the posterior regions (parietal and occipital), the amount of endogenous alpha power did not differ markedly from that of exogenous alpha power. The posterior regions, which generate more endogenous alpha activity, can be considered to play a dominant role in alpha generating mechanisms. In some subjects, alpha generators with a different frequency from that of the occipital areas were observed.