Abstract
The purpose of this research was to examine the state of the activity of the prefrontal area during the calculation tasks in the morning and the afternoon by non-invasive the Near Infrared Spectroscopy (NIRS). The NIRS was studied for 8 volunteers (30.5±5.9 y).As a method, the near infrared rays light with a high permeability (wavelength 775, 810, 850 nm) was irradiated from the outside, and the state of the hemoglobin in blood that flowed in the tissue was measured by analyzing light that had permeated the tissue. The change of hemoglobin dynamics were sampled at 2Hz, 2ch (HAMAMATSU Corporation, NIRO-200).As the result, an increase of oxy-Hb (hemoglobin of making to oxygen) of the head was suspected for calculation tasks. And the tendency to increase was showed, when the first half of the calculation tasks was compared with the latter half. But the difference in the morning and the afternoon was not admitted.More detailed tasks to calculate will be measured by NIRS in future. [J Physiol Sci. 2007;57 Suppl:S163]
