Threshold for periodic tone pulses as a function of duration and repetition rate in the normal auditory system is controlled by a time constant of the order of 200–300 msec. Thresholds measured in the neurally impaired ear are greatly influenced by the fact that neural adaptation increases as (1) the time interval between pulses decreases (below 200 msec), and (2) the duration of the signal is prolonged. Threshold measures further reflect variations in response behaviors such as reaction time. For any one individual, the time constant of the ear is related to a critical “decay” time that depends on both signal duration and interstimulus interval. In standard audiometric practice, lengthened signal durations combined with short off‐intervals strain already altered time constants in neurally impaired ears, leading subjects to trade intensity for the critical times necessary to perceive the signal. An adaptive method in which signal duration, off‐interval, repetition rate, and time for subject response are controlled and defined will avoid the adverse intensity‐for‐time trade that can occur during conventional psychoacoustic measures of threshold in auditory pathology. [Research supported in part by grants from the NINDS of the U. S. Public Health Service.]