Energetic and informational masking effects of hospital noise

Abstract

The ability to understand speech in a hospital setting is limited by the overlap of speech and noise energy at the level of the cochlea, sometimes called “energetic masking.” However, there are also additional “informational masking” effects that can occur when the noise is comprised of informational sounds such as speech, alarms, or other meaningful auditory events (e.g., Kidd and Colburn, 2017). While energetic overlap has been well-studied and is quantified in a number of international standards such as the Speech Intelligibility Index (ANSI, 2004), there is no similar metric for informational masking. Two of the main difficulties with predicting informational masking, and thus the intelligibility of speech in real world environments, are 1) the lack of tools that defines the meaningfulness of an interfering sound and 2) the much greater variability in susceptibility of individual listeners to informational as opposed to energetic masking. These ideas will be illustrated with data from several recent studies of speech intelligibility with various types of maskers, including hospital noise, and several current and emerging techniques for assessing speech intelligibility for individual listeners in simulated environments will be described.