Publications by authors named "Masaki Fumoto"

To gain insight into the neurophysiological mechanisms involved in Zen meditation, we evaluated the effects of focused attention (FA) on breathing movements in the lower abdomen (Tanden) in novices. We investigated hemodynamic changes in the prefrontal cortex (PFC), an attention-related brain region, using 24-channel near-infrared spectroscopy during a 20-minute session of FA on Tanden breathing in 15 healthy volunteers. We found that the level of oxygenated hemoglobin in the anterior PFC was significantly increased during FA on Tanden breathing, accompanied by a reduction in feelings of negative mood compared to before the meditation session.

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Relationships between deficits in verbal fluency and poor social functioning have been revealed in patients with schizophrenia. In previous studies, we demonstrated that deficits in idea fluency, which is ranked as a more complex type of verbal fluency and reflects divergent thinking ability, were more closely related to social dysfunction than deficits in simple word fluency. Although functional neuroimaging studies have provided detailed data regarding prefrontal dysfunction during word fluency tasks, the regions that relate to deficits in fluency of ideas and thoughts have not yet been clarified in schizophrenia patients.

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We have proposed a concept that prolonged rhythmic gum chewing causes a suppressed nociceptive flexion reflex via the serotonergic (5-HT) descending inhibitory pathway. However, the mechanism of activation of the 5-HT system by gum chewing remains undetermined. Several human and animal studies have reported that a direct connection exists between the prefrontal cortex (PFC) and 5-HT neurons in the dorsal raphe nucleus; therefore, we hypothesized that activation of the PFC region might be responsible for augmented 5-HT activity.

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This study evaluates a possible involvement of the prefrontal cortex (PFC) and serotonergic (5-HT) system in psychiatric and electroencephalography (EEG) changes during and after pedaling exercise (PE). The subjects performed PE for 15 min using a cycle ergometer. PE rate was kept at 60 rpm, and the work load (93+/-5.

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The present study re-evaluated an existing notion that serotonin (5-hydroxytryptamine; 5-HT) could not cross the brain to the circulating blood via the blood-brain barrier (BBB). To elevate brain 5-HT alone, 5-hydroxytryptophan (5-HTP; 30-75 mg/kg) was administrated intravenously to anaesthetized rats that had undergone gastrointestinal and kidney resections along with liver inactivation (organs contributing to increasing blood 5-HT after 5-HTP administration). A microdialysis method and HPLC system were used to determine the brain 5-HT levels in samples collected from the frontal cortex.

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In the present study, the extent to which the early component of somatosensory evoked potentials (SEPs) and the Hoffmann (H-) reflex induced by stimulation of the posterior tibial nerve are altered during the ascending and descending phases of fast plantarflexion was investigated. SEPSs and H-reflex of the soleus following tibial nerve stimulation were examined during fast plantarfiexion when performed by nine normal subjects. The analyses focused on differences in amplitude modulation of the P30-P40 component of SEP and the H-reflex between the ascending and descending phases of full-wave rectified and averaged soleus electromyographic (EMG) activity.

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Our previous studies have suggested that activation of the hypothalamic paraventricular (PVN) descending oxytocinergic projections is involved in the induction of yawning accompanied by an arousal response, but the possibility that neural systems other than the oxytocinergic system in the PVN also mediate the arousal/yawning response cannot be ruled out. We assessed the activity of corticotropin-releasing factor (CRF) neurons during yawning induced by the PVN stimulation in anesthetized, spontaneously breathing rats using double-staining for c-Fos and CRF. Yawning response was evaluated by monitoring an intercostals electromyogram as an index of inspiratory activity and a digastric electromyogram as an indicator of mouth opening.

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Serotonergic (5-HT) neurons are implicated in modulating nociceptive transmission. It is established that 5-HT neuronal activity is enhanced by rhythmic behaviors such as chewing and locomotion in animals. We thus hypothesized that 5-HT descending inhibitory pathways may be enhanced by rhythmic behavior of gum chewing in humans.

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This study examined the effects of voluntary abdominal breathing (VAB) on the electroencephalogram (EEG) in 22 healthy subjects. VAB was characterized by prolonged rhythmic contraction of abdominal muscles for 20 min in an eyes-closed condition. The breathing rate was instructed to be very slow, i.

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Unlabelled: We constructed a website for inferring a network by applying the graphical Gaussian model, from a large amount of data, including redundant information. The available tools on the website are based on a system, named ASIAN (Automatic System for Inferring A Network), in combination with the two methods in our previous papers, which were designed to analyze gene expression profiles on a genomic scale. One of the remarkable features of the website is its ability to infer a network, concomitant with hierarchical clustering and the following estimation of cluster boundaries.

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The relationship between the size of the soleus (Sol) Hoffmann (H-) reflex and the level of background (BG) electromyographic (EMG) activity was examined during plantarflexing at different force levels. The experiments were carried out on seven healthy male subjects aged 20-37 years. The subjects were asked to perform fast plantarflexion under a reaction-time condition.

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Genome Information Broker (GIB) is a powerful tool for the study of comparative genomics. GIB allows users to retrieve and display partial and/or whole genome sequences together with the relevant biological annotation. GIB has accumulated all the completed microbial genome and has recently been expanded to include Arabidopsis thaliana genome data from DDBJ/EMBL/GenBank.

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