On the generalization of tones: A detailed exploration of non-speech auditory perception stimuli

The dynamic changes in natural sounds’ temporal structures convey important event-relevant information. However, prominent researchers have previously expressed concern that non-speech auditory perception research disproportionately uses simplistic stimuli lacking the temporal variation found in natural sounds. A growing body of work now demonstrates that some conclusions and models derived from experiments using simplistic tones fail to generalize, raising important questions about the types of stimuli used to assess the auditory system. To explore the issue empirically, we conducted a novel, large-scale survey of non-speech auditory perception research from four prominent journals. A detailed analysis of 1017 experiments from 443 articles reveals that 89% of stimuli employ amplitude envelopes lacking the dynamic variations characteristic of non-speech sounds heard outside the laboratory. Given differences in task outcomes and even the underlying perceptual strategies evoked by dynamic vs. invariant amplitude envelopes, this raises important questions of broad relevance to psychologists and neuroscientists alike. This lack of exploration of a property increasingly recognized as playing a crucial role in perception suggests future research using stimuli with time-varying amplitude envelopes holds significant potential for furthering our understanding of the auditory system’s basic processing capabilities.