New data on perceptual phenomenon in auditory judgment

Report

Singapore noise
© Petr Vaclavek-Fotolia

Researchers from France, the UK, and the US recently reported results of a study showing that prior context in audition has a considerable effect on basic auditory judgement.

Perceptual processing relies on the senses but scientists believe that the senses alone are not necessarily sufficient to help us determine the exact state of the perceived reality. They suspect that resolving this intrinsic ambiguity is a crucial part of perceptual processing and may call on prior context to disambiguate sensory information.

To test this phenomenon in hearing, the researchers included between nine and ten self-reported normal-hearing listeners in five of their experiments, and one hundred unscreened listeners in one experiment. The team developed pairs of tones with ambiguous transitions between frequency components so that listeners were equally likely to report an upward or downward pitch shift between tones. It was found that presenting context tones before the ambiguous pair almost fully determined the direction of shift perceived by the study participants.

The results, published in Nature Communications in late April, provided “behavioural, neural and computational evidence showing that human auditory perception seamlessly binds prior context into current perceptual decisions, and that this influence is exerted over simple features over a wide range of sound parameters,” according to the authors. The article concludes that all the sounds we perceive imprint a predictive trace about the sounds that will follow.

Source: Chambers, C. et al. Prior context in audition informs binding and shapes simple features. Nature Communications. 2017 Apr 20;8:15027

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