Intensity discrimination in noise: Effect of aging

Intensity discrimination thresholds for a 70 dB SPL, 500-Hz pure tone presented in quiet, broadband, and notched noise were measured for six younger and older adults all with good audiograms using a two-alternative forced-choice paradigm. All six younger adults had smaller thresholds in the broadband-noise compared to the notched-noise condition. The majority of the older adults had much larger thresholds than the younger adults in the broadband-noise condition and there was no significant difference between their thresholds in broadband and notched-noise conditions. This pattern of findings suggests that most of the older adults had difficulty making use of the temporal fine structure cues available in the broadband-noise condition, consistent with a possible age-related decline in temporal synchrony coding.