Does Temporal Predictability Enhance Auditory Temporal Resolution? Behavioral Results from a Gap Detection Paradigm

Perception takes advantage of the dynamic structure of our sensory environment. Temporal predictions of when an event will occur are built from temporal regularities, and used to orient attention in time. These temporal predictions improve motor responses to, and perceptual processing of, predicted inputs. Here, we studied whether the perceptual benefits from temporal predictions can be explained by an enhanced temporal resolution of the sensory system. Studies in the visual modality indeed showed that temporal resolution was improved by non-rhythmic temporal predictions, derived from a predictive foreperiod interval separating two events.To extend this finding to the auditory modality, we combined a gap detection task, assessing temporal resolution, with a foreperiod paradigm inducing non-rhythmic temporal predictions. 26 human participants were behaviorally tested on a two-alternative-forced-choice version of the gap detection task. We measured performance for varying gap durations by means of psychometric curves. To induce temporal predictability, we kept the foreperiod intervals between the onset of the stimulus and the gap constant in half of the blocks. In the other blocks, the foreperiod intervals were randomly varied. Our analyses showed that temporal predictions did not improve the performance in the gap detection task. However, response time improvements did indicate the use of temporal predictions, and suggested a possible decrease of decision times by temporal predictability. Hence, non-rhythmic temporal predictions did not benefit auditory temporal resolution as we operationalized it. Further research is needed to assess the generality of these findings.