“…The characteristic presbycusic deficit seen in all normative data is a gradually sloping, high-frequency hearing loss. The loss increases gradually at first and then accelerates more rapidly with increasing age, especially for the higher frequencies (Berger et al, 1977;Corso, 1963;Glorig & Nixon, 1960;Glorig & Nixon, 1962;Glorig & Roberts, 1965;Robinson & Sutton, 1979;Spoor, 1967), and is bilaterally symmetrical (Dayal, Kane & Mendelsohn, 1970;Klotz & Kilbane, 1962;Sataloff & Menduke, 1957). However, not all presbycusic hearing losses follow the typical audiometric configuration.…”