AGE-ASSOCIATED DEGENERATION OF BACKWARD-MASKING TASK-PERFORMANCE - EVIDENCE OF DECLINING TEMPORAL RESOLUTION ABILITIES IN NORMAL LISTENERS

A backward masking paradigm was employed to investigate temporal resol ution capabilities in normal-hearing subjects of increasing chronologi cal age. Results have documented: (1) a 2-, 4-, 8-, and 11-fold decibe l magnitude difference for averaged psychoacoustic functions when comp aring data obtained from young adults to those of elderly listeners; ( 2) that backward masking function slopes become significantly steeper with age, especially at very short interstimulus intervals; (3) a sign ificant interaction between age and target frequency; (4) a linear age -associated decrement in presumed temporal resolution abilities, and ( 5) no significant target frequency difference nor any ear differences existed. Both end organ and central nervous system mechanisms were con sidered in explaining these findings.