Author(s)

Noriyuki Kamata, Yoshimi Matsuo, Ayako Matsuya, Satoru Inoue, Kazuo Abe

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The purpose of this study was to investigate neuronal mechanisms active during the percep-tion of forward postural limits in a standing po-sition and to specify fall-related brain activity using optical functional near-infrared spectros-copy. The study group included six right-handed, healthy female volunteers (range: 19, 20 years). The optical imaging device comprised 16 opto-des designed to provide 24-channel recording of changes in hemoglobin oxygenation. We meas-ured the changes of oxygenated hemoglobin levels in the frontal region when subjects per-ceived reachability in a standing position. Com- pared with those in other regions, the oxygen-ated hemoglobin levels in the right frontal region compatible with the right prefrontal cortex sig-nificantly increased. This result suggests that brain activities in the right prefrontal cortex are related to perception of reachability. Overesti-mation of postural limits has been reported as one of the risk factor for falling. This overesti-mation might be induced by dysfunction in the prefrontal cortex, resulting in a failure to inhibit a motor program that would have caused a loss of balance in reaching. Activation of the right prefrontal cortex may be a key factor for pre-venting accidental falls in the elderly and in pa-tients with neurological disorders.

Postural Limits; Falls; Functional Near-Infrared Spectroscopy (fNIRS); Prefrontal Cortex (PFC)

Kamata, N. , Matsuo, Y. , Matsuya, A. , Inoue, S. and Abe, K. (2009) Right prefrontal cortex is activated for perceiving postural limits: a functional near-infrared spectroscopy study. Health, 1, 239-243. doi: 10.4236/health.2009.13039.