The human cerebellum is essential for modulating perceptual sensitivity based on temporal expectations
A functional benefit of attention is to proactively enhance perceptual sensitivity in space and time. Although attentional orienting has traditionally been associated with cortico-thalamic networks, recent evidence has shown that individuals with cerebellar degeneration (CD) show a reduced reaction time benefit from cues that enable temporal anticipation. The present study examined whether the cerebellum contributes to the proactive attentional modulation in time of perceptual sensitivity. We tested CD participants on a non-speeded, challenging perceptual discrimination task, asking if they benefit from temporal cues. Strikingly, the CD group showed no duration-specific perceptual sensitivity benefit when cued by repeated but aperiodic presentation of the target interval. In contrast, they performed similar to controls when cued by a rhythmic stream. This dissociation further specifies the functional domain of the cerebellum and establishes its role in the attentional adjustment of perceptual sensitivity in time in addition to its well-documented role in motor timing.
De-identified source data files for all figures and analyses in the article have been provided. Additional demographic information was not uploaded as it was not used in any analysis reported in the text, and can be provided upon request in personal communication with the corresponding author, without additional restrictions.
Article and author information
National Institutes of Health (NS092079)
- Richard B Ivry
National Institutes of Health (NS116883)
- Richard B Ivry
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: All participants provided informed consent to participate in the study and for the publication of de-identified data. The study was approved by the Institutional Review Board at the University of California, Berkeley (CPHS# 2016-02-8439).
- Marisa Carrasco, New York University, United States
- Received: January 21, 2021
- Accepted: June 23, 2021
- Accepted Manuscript published: June 24, 2021 (version 1)
- Version of Record published: June 30, 2021 (version 2)
© 2021, Breska & Ivry
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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