Terence W. Picton
Human Neurosci. Res. Unit, Univ. of Ottawa, 451 Smyth Rd., Ottawa, ON K1H 8M5, Canada
While studying the human electroencephalogram, Hallowell and Pauline Davis made the first recordings of the human auditory evoked potentials. In 1939 they published the founding papers for evoked potential audiometry: One by Pauline on recordings during wakefulness and a second by Hallowell on recordings during sleep. Although the possible audiometric usefulness of these responses was recognized, it was not until the 1960's that new averaging computers made their recording sufficiently objective for clinical use. In the 60's and early 70's, Hallowell and his colleagues then produced a series of definitive papers on the acoustical characteristics and clinical usefulness of the auditory ``vertex potential.'' While studying the effects of attention on this response, Hallowell made the first recordings of the P300 wave that is related to human information processing. For the last 15 years of his life, Hallowell put together techniques for evaluating frequency-specific thresholds in infants and young children with the auditory brain-stem response, proposing special stimuli (the 2-1-2 toneburst) and special response measurements (the SN10 wave). Hallowell Davis has been considered the ``father of evoked potential audiometry'': He was there at the beginning and continuously assisted the development of the field with careful research and insightful review.