This study explored the effects of various tasks, designed to alter the degree of “attention to stimuli” on the variability of the EEG activity which gives rise to the average acoustically evoked response. Evoked responses to 50 dB SL clicks were recorded from the vertex of eight male subjects under four conditions (1) quiet, (2) .counting, (3) discriminating, and (4) reading. Results showed the quiet condition to yield the greatest variability while reading exhibited the least.