Encyclopedia of Animal Cognition and Behavior

Living Edition
| Editors: Jennifer Vonk, Todd Shackelford

The Comparator

  • Jessica X. Brooks
  • Kathleen E. CullenEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-47829-6_217-1


The theoretical concept of a “comparator” has been proposed in order to explain how the brain distinguishes sensory information that is expected based on our own voluntary behaviors versus that generated by events in the external world. Specifically, the comparator is thought to subtract the motor-based estimate of sensory inflow from actual sensory signal to suppress the representation of expected stimuli. This self-monitoring mechanism ensures accurate motor control and stable perception.


It is important to correctly detect our own actions in order to effectively interact with and build an accurate representation of our environment. However, our sensory systems are activated by both external events (sensory exafference) and our own actions (sensory reafference). The prevailing view is that the brain largely achieves control of posture and accurate perceptual representation of the environment during voluntary actions by suppressing self-generated sensory...
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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of PhysiologyMcGill UniversityMontrealCanada
  2. 2.Biomedical EngineeringThe Johns Hopkins UniversityBaltimoreUSA

Section editors and affiliations

  • Joseph Boomer
    • 1
  1. 1.University at BuffaloBuffaloUSA