Health and Behavior Sciences
Online ISSN : 2434-7132
Print ISSN : 1348-0898
Volume 6, Issue 2
Displaying 1-6 of 6 articles from this issue
  • Toru Ozawa, Akio Mori, Masaki Takayose, Masami Osawa
    2008 Volume 6 Issue 2 Pages 37-42
    Published: 2008
    Released on J-STAGE: June 18, 2020
    JOURNAL FREE ACCESS

      In order to determine how the direction of motion of a moving visual target influences the brain activity related to timing control, we examined the pattern in which brain wave components occurred in the cerebral cortex of humans during 2 timing control tasks in which the direction of motion of a moving visual target differed. The subjects were 6, healthy, right-handed adults. We used 2 tasks: the anticipation of timing task with target that moves from the right to the left (timing task), and the reverse of this task, i.e., with a target that moves from the left to the right (reversed timing task). The target was displayed on a computer monitor placed approximately 1.3 m away from the subject. Electroencephalograms (EEGs) were recorded using electrodes placed at 128 sites on the scalp. The EEGs were separated into frequency bands of the alpha and beta components by using fast Fourier transform (FFT) analysis, and these bands were then analyzed. In addition, the alpha and beta components were compared between the timing task and reversed timing task at each of 18 sites selected according to the international 10/20 system excluding Cz. We observed a decrease in the alpha component and an increase in the beta component in the left frontal area during the reverse timing task. We consider that this activity reflects ocular movement to the right side. Moreover, a significant difference between the 2 tasks was observed with regard to the right posterotemporal area that was related to prediction, and this suggested that the posterotemporal area was related to timing control for visual stimuli.

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  • Masaki Takayose, Akio Mori, Toru Ozawa, Masanori Yamamoto
    2008 Volume 6 Issue 2 Pages 43-48
    Published: 2008
    Released on J-STAGE: June 18, 2020
    JOURNAL FREE ACCESS

      We investigated that the beta band, a frequency component of electroencephalogram (EEG), shows chronological changes in cerebral information processing during a simple reaction task and an oddball task that used a visual stimulus. The cerebral activity patterns in both the tasks were compared and analyzed in order to demonstrate the discrimination and differences in information processing. Fifteen right-handed healthy subjects participated in the study. The subjects were instructed to press a button with the right thumb as quickly as possible when a target stimulus was presented from a computer display. The EEG was recorded from the scalp using 128 channels, and was then filtered for the beta band (13-30 Hz). The chronological changes in the beta band in the left and right cerebral cortices showed characteristic activity patterns. Initially, the activity reached the visual cortex from the visual stimulus, and then it was transmitted to the temporal and the parietal association areas. Finally, the activity was transmitted from these areas to the frontal association area. The activities of these pathways occurred repetitively twice during the simple reaction task and thrice during the oddball task. The frequencies of activity in all the association areas were higher in the oddball task than in the simple reaction task, and the rate of increase in the activities in both the frontal association areas was remarkable. These results suggest that repeated activities of visual streams reflect visual information processing, and higher cognition of figures is possible if this activity increases. In addition, the frontal association areas are important for discrimination.

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  • Satoshi Takizawa
    2008 Volume 6 Issue 2 Pages 49-55
    Published: 2008
    Released on J-STAGE: June 18, 2020
    JOURNAL FREE ACCESS

      This study aims to examine the characteristics of motor imagery function in the pervasive developmental disorder children (PDD children: age 10.8 ± 1.7, IQ 75.2 ±17.4, total 7). After a series of bodily movements being presented for them and the normal school aged children, this study required for them to select cards where a series of movement was drawn appropriately, and to express a series of it. The author categorized the participants into the four groups which were the PDD group, a lower grade (age 7.5 ± 0.08, total 38), a middle grade (age 9.5 ± 0.08, total 36), and a higher grade (age 11.5 ± 0.08, total 38) and compared each group. The results showed that the rate of the maximum card misidentification in the PDD group exposed further from the groups of normal children. Therefore, the undeveloped body schema in the PDD group might reflect this factor.

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  • Kazuyuki Oka, Miki Sakamoto, Masaki Nakamura, Masuo Muro
    2008 Volume 6 Issue 2 Pages 57-61
    Published: 2008
    Released on J-STAGE: June 18, 2020
    JOURNAL FREE ACCESS

      Satellite cells are the stem cells of skeletal muscle and they play an important role in the regeneration process. Understanding the activities of satellite cells well is essential to investigate the regeneration including hypertrophy, but it is difficult to distinguish satellite cells from myonuclei using a light microscope because the cytoplasm is extremely small. Immunohistochemical markers to identify satellite cells are reported but no general consensus on this has been reached among researchers. A transmission electron microscope (TEM) is the only definitive identification method for satellite cells even today. However, the observation area of the TEM section is limited and it requires a tremendous effort to make the specimen for TEM. In order to overcome these difficulties of TEM, we applied a scanning electron microscope (SEM). The goal of this study is to verify the appropriateness based on the satellite cell identification methods by SEM.

      In this study, the soleus muscles of 3-week-old and 12-week-old female ICR mice were used. Paraffin section were made and after sputter coating with Pt-Pd, the specimens were observed with SEM. Randomly the nuclei located inside the basal lamina were observed and the number of satellite cell nuclei per total number of nuclei was calculated as the rate of satellite cells in each animal. The ratio of satellite cells was compared with the previously published data of TEM.

      The rate of satellite cells was 7.5% on average in 12-week-old soleus muscle and it was 11.7% in 3-week-old soleus muscle. That is, the rate was significantly higher in young animals (P<0.0001). This age-related decreasing tendency coincided with the results in rat soleus muscle using TEM (Gibson et al. 1983). The rate of satellite cells in our experiments was almost the same as the TEM results in mouse soleus muscle (Snow 1981).

      Making specimens for SEM is easy compared to the specimens for TEM and, therefore, SEM is certain to be used widely to identify satellite cells in the future.

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