著者

Sawahata Hirohito Toda Haruo Suzuki Takafumi Hasegawa Isao

出版者

Niigata University School of Medicine

雑誌

Acta medica et biologica = Acta medica et biologica (ISSN:05677734)

巻号頁・発行日

vol.58, no.2, 2011-09

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The primary visual cortex (V1) of the rat consists of a monocular (contralateral-eye-dominant) region (V1M) and a binocular region (V1B) that receives anatomical and functional inputs converging from both eyes. However, V1B contains a heterogeneous mosaic of neurons stochastically discharging with various degrees of ocular dominance, and it has been difficult to 5 estimate the size and behavior of the neuronal populations recruited by stimulation to individual eyes. To functionally characterize the V1B, we explore the similarities and differences of activation patterns between the contralateral and ipsilateral visual stimulation conditions in V1. Using a high density electrode array, 32-channel electrocorticogram (ECoG) was recorded from the whole surface of V1 of anesthetized Long-Evans rats. Despite a similarity of the spatial 10 activation patterns in the early phase, contralateral eye stimulation evoked consistently stronger responses and higher signal coherency between the most responsive site and adjacent sites than ipsilateral stimulation. Time-frequency analyses confirmed that contralateral activations were more widely distributed from V1B to V1M in low frequency powers (2-30 Hz). On the other hand, high frequency powers (30-100 Hz) were localized in V1B. These findings revealed 15 time-frequency domain properties of V1B. We speculate that the sustained high frequency activity reflected visual information flow from V1B to higher cortical centers.

著者

Fujinawa Osamu Endo Naoto Sakada Takenori

出版者

新潟大学

雑誌

Acta medica et biologica (ISSN:05677734)

巻号頁・発行日

vol.55, no.1, pp.23-34, 2007-03

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The objective of this study was to investigate the relationship between health-related quality of life (HRQOL) and physical fitness levels (PFLs) in elderly women with low bone mass and without fractures, with a further goal of developing preventive programs involving efficient exercises for osteoporotic fractures and falls. The subjects comprised 133 females over 65 years of age whose quantitative ultrasound (QUS) values were < 90% of the young adult means (YAM). Muscle strength (knee extensors, hand grip, and trunk flexors), flexibility, one-leg standing time with eyes open (one-leg stand), time required for a 10-m walk while stepping over six obstacles (10-m walk), and 6-min walking distance (6-min walk) were measured to assess PFL. The subjects' HRQOL scores were relatively high (122.5 ± 15.5; maximum, 160 points) despite their low PFLs, as compared to the Japanese standard PFL in a similar age group. An age-adjusted stepwise multiple regression analysis between PFLs and QUS or HRQOL in 115 subjects which all measurements were performed, revealed that the 10-m walk significantly contributed to the QUS (R2 = 0.152, p = 0.001) and to the total HRQOL score (R2 = 0.025, p = 0.039). With regard to the PFLs, the 6-min walk and one-leg stand contributed to the 10-m walk (R2 = 0.470, p = 0.012). In conclusion, the 10-m walk was observed to be a good indicator for the estimation ofHRQOL and PFLs; subsequently, balance exercise, brisk walking, and endurance walking are good exercises that can be included in preventive programs to maintain a high HRQOL.