Recent attempts to predict individual differences in TTS and PTS

Abstract

From the outset, large individual differences in temporary threshold shift (TTS) and permanent threshold shift (PTS) have been apparent in the results of studies on the effects of noise on hearing. A hypothesis proffered almost fifty years ago suggested that the TTS resulting from a brief exposure to a moderately intense exposure stimulus might be a good predictor of the PTS incurred by that same individual following repeated exposures to more intense acoustic stimulation. In the ensuing fifty‐year period, numerous investigations have attempted to establish this “simple” relationship between TTS and PTS. The end result of five decades of research in this area has been the realization that the relationship between TTS and PTS is not a simple one. One new approach to the quantification of TTS data, however, has produced a new index called the integrated temporary threshold shift (ITTS) which shows more promise as a predictor of PTS. In addition, much recent research has focused on using the results of non‐TTS paradigms to predict individual differences in noise‐induced TTS. These new developments and their implications for research and industry will be reviewed.