title: An Adapting Auditory-motor Feedback Loop Can Contribute to Generating Vocal Repetition.
abstract: Consecutive repetition of actions is common in behavioral sequences. Although integration of sensory feedback with internal motor programs is important for sequence generation, if and how feedback contributes to repetitive actions is poorly understood. Here we study how auditory feedback contributes to generating repetitive syllable sequences in songbirds. We propose that auditory signals provide positive feedback to ongoing motor commands, but this influence decays as feedback weakens from response adaptation during syllable repetitions. Computational models show that this mechanism explains repeat distributions observed in Bengalese finch song. We experimentally confirmed two predictions of this mechanism in Bengalese finches: removal of auditory feedback by deafening reduces syllable repetitions; and neural responses to auditory playback of repeated syllable sequences gradually adapt in sensory-motor nucleus HVC. Together, our results implicate a positive auditory-feedback loop with adaptation in generating repetitive vocalizations, and suggest sensory adaptation is important for feedback control of motor sequences.
authors.affiliation: Department of Physics and Center for Neural Engineering, the Pennsylvania State University, University Park, Pennsylvania, United States of America.
authors.forename: Jason D
authors.initials: JD
authors.lastname: Wittenbach
authors.affiliation: Department of Physiology and Center for Integrative Neuroscience, University of California at San Francisco, San Francisco, California, United States of America; Department of Neurosurgery and Center for Neural Engineering and Prosthesis, University of California at San Francisco, San Francisco, California, United States of America.
authors.forename: Kristofer E
authors.initials: KE
authors.lastname: Bouchard
authors.affiliation: Department of Physiology and Center for Integrative Neuroscience, University of California at San Francisco, San Francisco, California, United States of America; Howard Hughes Medical Institute, San Francisco, California, United States of America.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Brainard
authors.affiliation: Department of Physics and Center for Neural Engineering, the Pennsylvania State University, University Park, Pennsylvania, United States of America.
authors.forename: Dezhe Z
authors.initials: DZ
authors.lastname: Jin
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology*; D001306:Auditory Pathways / Q000502:physiology; D003198:Computer Simulation; D004525:Efferent Pathways / Q000502:physiology; D025461:Feedback, Physiological / Q000502:physiology; D008297:Male; D008959:Models, Neurological; D009044:Motor Cortex / Q000502:physiology*; D009068:Movement / Q000502:physiology; D020308:Songbirds / Q000502:physiology*; D014828:Vocalization, Animal / Q000502:physiology*