Functional cell types in the mouse superior colliculus
Abstract
The superior colliculus (SC) represents a major visual processing station in the mammalian brain that receives input from many types of retinal ganglion cells (RGCs). How many parallel channels exist in the SC, and what information does each encode? Here we recorded from mouse superficial SC neurons under a battery of visual stimuli including those used for classification of RGCs. An unsupervised clustering algorithm identified 24 functional types based on their visual responses. They fall into two groups: one that responds similarly to RGCs, and another with more diverse and specialized stimulus selectivity. The second group is dominant at greater depths, consistent with a vertical progression of signal processing in the SC. Cells of the same functional type tend to cluster near each other in anatomical space. Compared to the retina, the visual representation in the SC has lower dimensionality, consistent with a sifting process along the visual pathway.
Data availability
The data and code that produced the figures are available in a public Github repository https://github.com/yatangli/Li-CellTypes-2023
Article and author information
Author details
Funding
National Institute of Neurological Disorders and Stroke (R01 NS111477)
- Markus Meister
Simons Foundation (543015SPI)
- Markus Meister
National Eye Institute (K99EY028640)
- Ya-tang Li
Helen Hay Whitney Foundation
- Ya-tang Li
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 animal procedures were performed according to relevant guidelines and approved by the Caltech IACUC (protocol 1656).
Copyright
© 2023, Li & Meister
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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