The sifting of visual information in the superior colliculus
Abstract
Much of the early visual system is devoted to sifting the visual scene for the few bits of behaviorally relevant information. In the visual cortex of mammals a hierarchical system of brain areas leads eventually to the selective encoding of important features, like faces and objects. Here we report that a similar process occurs in the other major visual pathway, the superior colliculus. We investigate the visual response properties of collicular neurons in the awake mouse with large-scale electrophysiology. Compared to the superficial collicular layers, neuronal responses in the deeper layers become more selective for behaviorally relevant stimuli; more invariant to location of stimuli in the visual field; and more suppressed by repeated occurrence of a stimulus in the same location. The memory of familiar stimuli persists in complete absence of the visual cortex. Models of these neural computations lead to specific predictions for neural circuitry in the superior colliculus.
Data availability
The data used in the manuscript as well as the analysis codes have been made available on CaltechDATA, under the accession number 1401 (doi:10.22002/D1.1401). We have provided the code for generating Figure 2 (fig2.m).
Article and author information
Author details
Funding
Simons Foundation (543015SPI)
- Markus Meister
National Science Foundation (Graduate Research Fellowship)
- Alvita Tran
National Institutes of Health (1R01NS111477)
- Markus Meister
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Fred Rieke, University of Washington, United States
Ethics
Animal experimentation: This study was performed according to approved institutional animal care and use committee (IACUC) protocols (#1656) of Caltech. All surgery was performed under isoflurane anesthesia and every effort was made to minimize suffering.
Version history
- Received: July 30, 2019
- Accepted: March 9, 2020
- Accepted Manuscript published: April 14, 2020 (version 1)
- Version of Record published: May 19, 2020 (version 2)
Copyright
© 2020, Lee 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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