Publisher Summary This chapter discusses the bilateral alpha rhythm in children during listening and looking. When humans are felling relaxed, drowsy, or in meditative states, the EEG clocks a predominance of alpha waves having a frequency between 8 and 12 Hz. If a subject in this state is given a problem to solve, the alpha waves are replaced by asynchronous beta waves having a frequency greater than 12 Hz. The percentage of alpha rhythm may thus be used as a rough measure of the amount of ongoing information processing at a particular cortical location. The more alpha rhythm that is present, the less ongoing information processing is assumed to be occurring. The experiment described in the chapter was intended as a preliminary investigation of the effects of cognitive task on children's bilateral alpha rhythm. The Alphaphone Brainwave Analyzers had several advantages—such as being portable and easily connected to the subject—they did not provide the desired precision in the collection and analysis of data. Ideally, in an experiment measuring EEG activity, it's desirable to have a continuous record of the overall alpha density in each hemisphere. A comparison of the area under the waveform in the alpha band in each hemisphere would then provide an accurate measure of the relative amount of alpha in each hemisphere during different cognitive tasks.
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