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Acupuncture therapy has been applied to various psychiatric diseases and chronic pain since acupuncture stimulation might affect brain activity. From this point of view, we investigated the effects of acupuncture on autonomic nervous system and brain hemodynamics in human subjects using ECGs, EEGs and near-infrared spectroscopy (NIRS). Our previous studies reported that changes in parasympathetic nervous activity were correlated with number of de-qi sensations during acupuncture manipulation. Furthermore, these autonomic changes were correlated with EEG spectral changes. These results are consistent with the suggestion that autonomic changes induced by needle manipulation inducing specific de-qi sensations might be mediated through the central nervous system, especially through the forebrain as shown in EEG changes, and are beneficial to relieve chronic pain by inhibiting sympathetic nervous activity. The NIRS results indicated that acupuncture stimulation with de-qi sensation significantly decreased activity in the supplementary motor complex (SMC) and dorsomedial prefrontal cortex (DMPFC). Based on these results, we review that hyperactivity in the SMC is associated with dystonia and chronic pain, and that in the DMPFC is associated with various psychiatric diseases with socio-emotional disturbances such as schizophrenia, attention deficit hyperactive disorder, etc. These findings along with the previous studies suggest that acupuncture with de-qi sensation might be effective to treat the various diseases in which hyperactivity in the SMA and DMPFC is suspected of playing a role., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Although local thermotherapy reduces mental stress and neck stiffness, its physiological mechanisms are still not fully understood. We speculated that local thermotherapy exerts its effect, in addition to its direct peripheral effects, through the central nervous system that is involved in controlling stress responses. In the present study, we investigated the effects of a heat- and steam-generating (HSG) sheet on cerebral hemodynamics and autonomic nervous activity using near-infrared spectroscopy (NIRS) and the electrocardiograms (ECGs). Thirteen healthy young female subjects participated in this study. HSG or simple (control) sheets were repeatedly applied to the neck for 120 s with 180 s intervals of rest between applications. During the experiment, brain hemodynamic responses (changes in Oxy-Hb, Deoxy-Hb, and Total-Hb) and autonomic nervous activity based on heart rate variability (HRV) were monitored. Subjective perception of neck stiffness and fatigue was significantly improved after application of the HSG sheet. NIRS findings indicated that the application of HSG sheets decreased Oxy-Hb concentration in the anterior-dorsal region of the medial prefrontal cortex (adMPFC), while increasing parasympathetic nervous activity and decreasing sympathetic nervous activity. Furthermore, changes in Oxy-Hb in the adMPFC were significantly and negatively correlated with those in parasympathetic nervous activity during application of the HSG sheet. These findings suggest that application of the HSG sheet to the neck region induced mental relaxation and ameliorated neck stiffness by modifying activity of the adMPFC., (Copyright 2010 Elsevier B.V. All rights reserved.)

Visual mental imagery is critical for successfully navigating the environment, which in turn activates many cortical regions simultaneously. Theta oscillation is implicated in navigation and brain synchronization. In this study, EEG coherence was analyzed during 3 tasks: subjects (1) mentally simulated jogging along the walls of a gym and pressed a button when they imagined arriving at a corner (jogging imagery task), (2) thought of and memorized one digit after pressing a button 5 times and recalled the digits sequentially after pressing the button again (digit imagery task), and (3) pressed a button (button pressing task). The results indicated that theta-wave (4-8 Hz) power was significantly higher in the frontal and parietal regions during the digit and jogging imagery tasks. Coherence at the theta band showed almost no differences between the button pressing and digit imagery tasks. Coherence between the distant regions, especially between the frontal and parieto-occipital regions and between interhemispheric regions, was significantly higher during the jogging imagery task. Increase in theta power during the jogging imagery task reflects working memory load to manipulate internal information. Theta oscillation appears to play an important role in large-scale synchronization to form the functional neuronal networks required for mental navigation.