Auditory evoked responses (ABR, MLR, SVR) and brain mapping in the elderly

The influence of age on evoked auditory brainstem responses (ABRs) is still a matter of controversy. It is well known that in the elderly the ABRs show a progressive latency shift of the principal components. While many authors have reported a I-V internal latency shift, others claim that there is not a delay in the central conduction time (CCT) with ageing. Middle latency auditory evoked responses (MLRs) are also reported to be impaired in the elderly, but the few results published need further investigations. This study investigates some of the controversial aspects of electrophysiological assessment of the auditory system in the elderly. 36 healthy subjects (18 males and 18 females), mean age 67.2 years +/- 5.8, underwent ABRs, MLRs and SVRs and SVRs brain mapping evaluation. All the data were compared with our normative data for young adults. Our results confirm previous reports of a latency shift of all principal components of ABR, but do not demonstrate a significant CCT impairment in the elderly. The MLRs, SVRs and brain mapping analysis also support this conclusion.