Exploring listeners' speech rate preferences

Fast speech may reduce intelligibility, but there is little agreement as to whether listeners benefit from slower speech in noisy conditions. The current study explored the relationship between speech rate and masker properties using a listening preference technique in which participants were able to control speech rate in real time. Spanish listeners adjusted speech rate while listening to word sequences in quiet, in stationary noise at signal-to-noise ratios of 0, +6 and +12 dB, and in modulated noise for 5 envelope modulation rates. Following selection of a preferred rate, participants went on to identify words presented at that rate. Listeners favoured faster speech in quiet, chose increasingly slower rates in increasing levels of stationary noise, and showed a preference for speech rates that led to a contrast with masker envelope modulation rates. Participants showed distinct preferences even when intelligibility was near ceiling levels. These outcomes suggest that individuals attempt to compensate for the decrement in cognitive resources availability in more adverse conditions by reducing speech rate and are able to exploit differences in modulation properties of the target speech and masker. The listening preference approach provides insights into factors such as listening effort that are not measured in intelligibility-based metrics.