The purpose of this study is to evaluate the brain activity in electroencephalogram (EEG) under the emotional stimuli using mobile computer. Twenty-four healthy subjects were evaluated for their psychosomatic level with Cornell Medical Index (CMI), State-Trait Anxiety Inventory—Japanese version (STAI), and stress check list (SCL) and divided into two groups: low psychological score group (LSG) and high psychological score group (HPG). EEG was measured under emotionally audio-visual tasks (relax, pleasant, and unpleasant) and emotional sentence tasks (pleasant sentence and unpleasant sentence) using audiovisual stimuli in the mobile computer. EEG was analyzed with a discrete Fourier transform (DFT) to obtain power spectra. The results showed that the power spectra in alpha 2 (10–14 Hz) band in temporal area under the unpleasant stimuli were significantly higher than the spectra under the relax stimuli in the mentally unstable group. These events suggest that the emotional stimuli on mobile phone would affect to their brain reaction related to the mental stability.

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Although SMA is thought to contribute to the generation of anticipatory postural adjustments (APAs), which act to stabilize supporting body segments prior to movement, its precise role remains unclear. Non-invasive brain stimulation, such as transcranial direct current stimulation (tDCS), over the primary motor cortex (M1) has been shown to modulate cortical excitability, thereby influencing motor behavior and learning. However, only a few studies have reported that application of tDCS over the SMA changes the excitability of the M1 and motor learning process. This study was performed to elucidate whether cathodal tDCS applied over the SMA modifies the function of APAs. Cathodal tDCS and sham tDCS (2 mA) were applied over the SMA or left of the leg area of the M1 of 11 healthy subjects for 15 min. Subjects performed the task of self-paced rapid shoulder flexion on before, immediately after, and 15 min after tDCS. Electromyographic (EMG) activity was recorded from the deltoid anterior (DEL_A), as the prime mover muscle, and biceps femoris (BF), as the postural muscle during tasks. Latency differences (ΔEMG onset) with the two types of stimuli were calculated by subtracting the EMG burst onset of the BF from that of the DEL_A. Following cathodal tDCS over the SMA, the ΔEMG onset was significantly shortened compared to after sham tDCS, while tDCS over the M1 did not produce any significant effect. These results suggest that the SMA may play a critical role in the generation of voluntary movement accompanied by APAs. Cathodal tDCS could have beneficial method to investigate the function of the SMA in virtual lesion studies.

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Music perception involves acoustic tone activity and scene (melody, harmony) analysis, as well as its processing of musical syntax and semantics, that lead to the activation of the prefrontal cortex (and active motor) actions. The present study aimed to clarify the underlying neural networks during music perception in musicians and non-musicians. We examined spontaneous brain activities in six musicians (five musically trained students and one singer), and five non-musically trained students while listening to Dvorak’s “From the new world” and Mozart’s “Requiem” for 150 seconds for each piece, imaging the music for 60 seconds thereafter, using 60-ch electroencephalography (EEG). The data were analyzed and compared with those of the resting state. We adopted Morlet wavelet time-frequency analysis, and root mean square (RMS) was calculated in each frequency-band (Delta: 1–4 Hz, Theta: 4–8 Hz, Alpha: 8–13 Hz, Beta: 13–30 Hz, Gamma 30–50 Hz). During listening to the music, gamma activity was significantly decreased in all of the regions. While imaging the music, the musicians’ gamma activity was significantly decreased in the entire cortical areas, whereas the non-musicians’ gamma activity increased in the frontal area. A gamma activity decreased during perception of the music, especially in the prefrontal cortex in musicians; it is strongly related to the integration of recognition and emotion which reflects the processing of music in a highly integrated consciousness level. The frontal gamma activity shown here may indicate that musicians image the music in the same or similar condition as they are listening to the music that is, they do image and replay the music in the implicit memory compiled from the explicit acoustic memory while listening to the music. The differences as evidently shown in music perception between well-trained and non-trained students may reflect the differences of their education in musical experiences and expert skills obtained in their music carrier.

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In an effort to accurately predict the outcome of peripheral facial palsy (PFP), we compared integrated electromyogram (integrated EMG) and evoked electromyogram (evoked EMG) data for their prognostic abilities. The subjects consisted of 123 patients with PFP. Patients who took six months or more to recover were defined as the poor outcome group, while those who took three months or less to recover were defined as the early recovery group. We measured activation in the orbicularis oculi muscle employing both integrated EMG and evoked EMG twice: shortly after and two weeks after the onset. Then, we computed the ratios of the electrical activity on the affected side to that on the intact side. Subsequently, we plotted a receiver operating characteristic curve in order to assess the accuracy of the classification of these patients into the aforementioned two outcome groups using each of the four electrical activity ratios. The area under the curve (AUC) was calculated to measure the accuracy of prediction. Logistic regression analysis was performed to determine which variables independently predicted outcomes. The most reliable method for predicting outcomes was the AUC of evoked EMG performed two weeks after the onset for both groups (The discriminatory power was 0.894 for the poor outcome group and 0.931 for the early recovery group). Logistic regression analysis also confirmed that outcomes were significantly related to the ratios (p<0.01). Further studies are required to increase the accuracy of identifying patients with a poor prognosis and to improve the reliability of predicting outcomes in the early stage of the disease.

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