Learning-related population dynamics in the auditory thalamus
Abstract
Learning to associate sensory stimuli with a chosen action involves a dynamic interplay between cortical and thalamic circuits. While the cortex has been widely studied in this respect, how the thalamus encodes learning-related information is still largely unknown. We studied learning-related activity in the medial geniculate body (MGB; Auditory thalamus), targeting mainly the dorsal and medial regions. Using fiber photometry, we continuously imaged population calcium dynamics as mice learned a go/no-go auditory discrimination task. The MGB was tuned to frequency and responded to cognitive features like the choice of the mouse within several hundred milliseconds. Encoding of choice in the MGB increased with learning, and was highly correlated with the learning curves of the mice. MGB also encoded motor parameters of the mouse during the task. These results provide evidence that the MGB encodes task- motor- and learning-related information.
Data availability
The data and custom code that support the findings of this study are publicly available at: https://osf.io/mt3bc/.
Article and author information
Author details
Funding
ERC consolidator grant (#616063)
- Adi Mizrahi
Israel Science Foundation (#224/17)
- Adi Mizrahi
Marie Sklodowska-Curie postdoctoral fellowship (659719)
- Ariel Gilad
Israel Science Foundation (#2453/18)
- Ariel Gilad
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 experiments were approved by Institutional Animal Care and Use Committee (IACUC) at the Hebrew University of Jerusalem, Israel (Permit Number: NS-19-15706-4).
Copyright
© 2020, Gilad 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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