Illusory perception of auditory filled duration is task- and context-dependent.

Area of Science:

• Auditory Perception
• Psychophysics
• Cognitive Neuroscience

Background:

• The filled-duration illusion demonstrates that auditory stimuli can alter time perception.
• Auditory sequences with clicks create empty intervals whose perceived duration may differ from isolated intervals.

Purpose of the Study:

• To investigate how task demands and context influence the perceived duration of single empty intervals compared to intervals within auditory sequences.
• To explore the factors modulating temporal illusions in auditory perception.

Main Methods:

• Five experiments were conducted using auditory stimuli, varying continuous tones, click sequences, and interval durations (e.g., 140 ms).
• Participants performed duration discrimination or comparison tasks involving isolated empty intervals, filled durations, and sequences of empty intervals.
• Specific manipulations included using oddball clicks to define target intervals within sequences.

Main Results:

• A 140 ms empty interval was perceived as longer than an equivalent inter-stimulus interval in a sound sequence (Experiments 1 & 3).
• The 140 ms empty interval was perceived as shorter than a 140 ms continuous beep (Experiment 2).
• A compression effect was observed, where a target empty interval (oddball clicks) was perceived as shorter than other equivalent intervals in a sequence (Experiment 4), and assimilation effects were noted (Experiment 5).

Conclusions:

• Perceived duration of auditory empty intervals is context-dependent and modulated by task demands.
• Bayesian inference provides a framework for explaining these contextually modulated temporal illusions.
• Findings highlight the dynamic and inferential nature of auditory time perception.