title: Variations in electroencephalographic alpha activity under conditions of differential lighting and auditory feedback.
abstract: The electroencephalographic alpha activity of 13 college students was monitored under conditions of darkness or dim light for six sessions, and for a seventh under the opposite condition. Auditory feedback was given for the presence of alpha activity during a 5-min orientation period and when during ten 2-min trial periods. The results indicate that: (1) alpha production in the presence of feedback did not exceed initial eyes-closed base line production; (2) introducing feedback immediately enhances alpha activity, rather than increasing production gradually; (3) under certain circumstances, dim light is sufficient to suppress alpha; and (4) after many sessions of alpha production in darkness, subjects maintain a given amount of alpha even when visual stimulation is present.
mesh_terms: D000328:Adult; D000513:Alpha Rhythm; D001676:Biofeedback, Psychology / Q000502:physiology*; D003624:Darkness; D005260:Female; D006801:Humans; D008027:Light; D008297:Male; D013016:Sound