Rate perception adapts across the senses: evidence for a unified timing mechanism.
The brain constructs a representation of temporal properties of events, such as duration and frequency, but the underlying neural mechanisms are under debate. One open question is whether these mechanisms are unisensory or multisensory. Duration perception studies provide some evidence for a dissociation between auditory and visual timing mechanisms; however, we found active crossmodal interaction between audition and vision for rate perception, even when vision and audition were never stimulated together. After exposure to 5 Hz adaptors, people perceived subsequent test stimuli centered around 4 Hz to be slower, and the reverse after exposure to 3 Hz adaptors. This aftereffect occurred even when the adaptor and test were different modalities that were never presented together. When the discrepancy in rate between adaptor and test increased, the aftereffect was attenuated, indicating that the brain uses narrowly-tuned channels to process rate information. Our results indicate that human timing mechanisms for rate perception are not entirely segregated between modalities and have substantial implications for models of how the brain encodes temporal features. We propose a model of multisensory channels for rate perception, and consider the broader implications of such a model for how the brain encodes timing.
Cognitive Science, Occidental College, 1600 Campus Road, Los Angeles CA 90041.
Carmel A
CA
Levitan
Cognitive Science, Occidental College, 1600 Campus Road, Los Angeles CA 90041.
Yih-Hsin A
YH
Ban
Computation and Neural Systems, California Institute of Technology, 1200 E. California Blvd, Pasadena, CA 91125.
Noelle R B
NR
Stiles
1] Computation and Neural Systems, California Institute of Technology, 1200 E. California Blvd, Pasadena, CA 91125 [2] Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Blvd, Pasadena, CA 91125.
Shinsuke
S
Shimojo
D000161:Acoustic Stimulation / Q000379:methods; D000222:Adaptation, Physiological / Q000502:physiology*; D001244:Association; D001307:Auditory Perception / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D003198:Computer Simulation; D005260:Female; D006801:Humans; D008297:Male; D008959:Models, Neurological; D009473:Neuronal Plasticity / Q000502:physiology; D010775:Photic Stimulation / Q000379:methods; D012677:Sensation / Q000502:physiology; D011984:Sensory Receptor Cells / Q000502:physiology; D013998:Time Perception / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult