Two theories of temporal summation in hearing were compared. In both theories the ear performs a running average on the incoming sound in accordance with the convolution integral. In one of the theories, called the ’’rectangular’’ theory, sound is transformed by a power function and weighted by a brief rectangular function; in the other theory, called the ’’exponential’’ theory, sound is transformed so that an initial large effect decays to a steady level and it is weighted by a decaying exponential function. The rectangular theory was shown to predict that brief tone bursts and brief gaps in a tone are equally detectable if the duration of the burst and gap are equal, but the exponential theory was shown to predict that brief tone bursts are more readily detectable than brief gaps of equal duration. Experimental findings support the exponential theory: The percentage of correct responses in a two‐alternative forced‐choice task was greater for tone bursts than for tone gaps of equal duration. This result was obtained for tones and gaps from 25 to 200 msec in duration and for two different levels of a 1000‐Hz tone. In addition, the exponential theory, with a time constant of 5 sec−1 for the weighting function, was compatible with the relation between the percentage of correct responses and the theoretical quantity determining detectability.
Subject Classification: [43]65.68, [43]65.50, [43]65.75.