The effect of reverberation on listening effort

The current study investigates whether long reverberation increases listening effort during speech recognition. Listening effort during word recognition in multi-talker babble noise was assessed with or without high levels of reverberation. A dual-task paradigm was adopted, in which the primary task was word recognition in noise at individually selected signal-to-noise ratio (SNR) that yielded an average performance level of 50% correct, and the secondary task was a visual-tracking task with individually adjusted difficulty level to yield an average performance level of 85% correct. In each 30-s trial, seven monosyllabic words were presented sequentially at a rate of four seconds per word. Young normal-hearing listeners were instructed to verbally repeat each word while performing the secondary task. In the reverberant condition, a cascade of all-pass filters was used to achieve a reverberation time of 1 s without altering the original spectrum of the speech. For the primary task in isolation, the reverberant condition required 10 dB or more in SNR to achieve the 50% target performance level. When the listeners performed the two tasks simultaneously, no consistent adverse effect of reverberation was found on the performance of the primary or secondary task compared to the no-reverberation condition.