Chronological Change in EEGs of a Child while Concentrating on Tasks

Physiological measurements during concentration on tasks have been carried out for three years with children who have been practicing a kind of image training and rapid reading. In this report, EEG changes of one subject, a 9-year-old boy in 2001, are reported. Measurements from three experi-ments were analyzed during tasks with the eyes closed. The tasks were resting, visual imaging and rapid reading using a blindfold (blind reading). Frequency of alpha waves became faster with age. The tendency for high frequency alpha waves during visual imaging and blind reading was clearer as the subject became older. The older the subject became, the larger the a amplitude on the occipital area became. But a suppression during rapid reading was observed at a lower age. During hypnosis-like induction of image and getting the contents of a book while blindfolded, the subject was considered to be in a so-called ASC (altered state of consciousness). In such a state, the ratio of the a amplitude on the frontal to the occipi-tal area (Fp2/O2) becomes usually large. In this work, the ratio became really large during rapid reading. At that time, lag time of alpha waves on the frontal to the occipital area, as an indicator of concentration, be-came shorter than in the resting state. The subject seemed to be in the concentrating state. Fm-shita which is considered to appear in deep concentration, was not observed so often for this subject. Bata waves tended to appear dominantly on the left hemisphere and only sometimes on the right or both occipital areas.