Temporal integration and presbycusis.

On 8 presbycusic Ss with similar sensorineural hearing losses, temporal integration (TI) was estimated by comparing HTLs for signal durations of 500 and 20 msec, at frequencies .5-6 kc/s. Normal-hearing young adult controls were also tested. Degree of group hearing loss for the presbycusic Ss was related to group TI data, but did not account for the amount of decrease in TI with these older Ss. Slightly reduced TI (6 db) was found in Ss' area of normal hearing even though the test frequency and adjacent frequencies were within a normal-hearing range. Reduced TI occurred most consistently in Ss with HTLs greater than or equal to 40 db. Individual variance suggested caution in using TI as a diagnostic clinical procedure.