Shared mechanisms of auditory and non-auditory vocal learning in the songbird brain
Abstract
Songbirds and humans share the ability to adaptively modify their vocalizations based on sensory feedback. Prior studies have focused primarily on the role that auditory feedback plays in shaping vocal output throughout life. In contrast, it is unclear how non-auditory information drives vocal plasticity. Here, we first used a reinforcement learning paradigm to establish that somatosensory feedback (cutaneous electrical stimulation) can drive vocal learning in adult songbirds. We then assessed the role of a songbird basal ganglia thalamocortical pathway critical to auditory vocal learning in this novel form of vocal plasticity. We found that both this circuit and its dopaminergic inputs are necessary for non-auditory vocal learning, demonstrating that this pathway is critical for guiding adaptive vocal changes based on both auditory and somatosensory signals. The ability of this circuit to use both auditory and somatosensory information to guide vocal learning may reflect a general principle for the neural systems that support vocal plasticity across species.
Data availability
Source data are provided for all main figures and relevant figure supplements (Figure 2b-f, Figure 2 - Figure Supplements 1-7, Figure 3b-e, Figure 3 - Figure Supplement 1, and Figure 4b-d). MATLAB code for generating these figures is also provided in the associated source code files. Data and source code have also been uploaded to a public data repository on figshare, in a project titled 'Shared mechanisms of auditory and non-auditory vocal learning in the songbird brain.'
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McGregor_et_al_Figure_2_Source_data_1.mat. figshare. Dataset.FigShare, 10.6084/m9.figshare.20183318.v1.
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McGregor_et_al_Figure_3_Source_Code_1.m. figshare. Software.FigShare, 10.6084/m9.figshare.20183312.v1.
Article and author information
Author details
Funding
National Institutes of Health (R01- EB022872)
- James N McGregor
- Abigail L Grassler
- Amanda Louise Jacob
- Samuel J Sober
National Institutes of Health (R01- NS084844)
- James N McGregor
- Abigail L Grassler
- Amanda Louise Jacob
- Samuel J Sober
National Institutes of Health (R01- NS099375)
- James N McGregor
- Abigail L Grassler
- Amanda Louise Jacob
- Samuel J Sober
Simons Foundation (Emory International Consortium on Motor Control)
- Samuel J Sober
Howard Hughes Medical Institute
- Paul I Jaffe
- Michael S Brainard
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experimental protocols were approved by the Emory University and UC San Francisco Institutional Animal Care and Use Committees (protocol #201700359)
Copyright
© 2022, McGregor et al.
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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