EFFECT OF TIME-SCALE MODIFICATION OF SPEECH ON THE SPEECH RECOGNITIONTHRESHOLD IN NOISE FOR ELDERLY LISTENERS

The effect of time scale modification of speech on the speech recognit ion threshold in noise (SRT(N)) was investigated for a group of 44 eld erly subjects, varying in age from 56 to 88 years with sloping mild-to -moderate sensorineural hearing losses. Subjects' pure-tone average th resholds at 500, 1000 and 2000 Hz (PTA1) ranged from 3 to 58 dB. The s tudy confirms the well-known fact that speech recognition in noise det eriorates with increasing age. Furthermore, time-compressing speech re sults in an even greater influence of age on the SRT(N). The apparent age effect on SRT(N) values referenced to SRT(N) in the control condit ion is mostly caused indirectly by the significant correlation between age and PTA1, although there was a slight tendency for age to have a greater independent effect on relative SRT(N) values when the amount o f time compression increased. The percentage of explained variance in relative SRT(N) values by the subject variables in this study was limi ted, indicating that there are other factors not investigated in this study (e.g. cochlear mechanisms, short-term memory, feature extractors ) that significantly influence the effect of time compression on SRT(N ).