Abstract
The representation of space in mouse visual cortex was thought to be relatively uniform. Here we reveal, using population receptive-field (pRF) mapping techniques, that mouse visual cortex contains a region in which pRFs are considerably smaller. This region, the “focea,” represents a location in space in front of, and slightly above, the mouse. Using two-photon imaging we show that the smaller pRFs are due to lower scatter of receptive-fields at the focea and an over-representation of binocular regions of space. We show that receptive-fields of single-neurons in areas LM and AL are smaller at the focea and that mice have improved visual resolution in this region of space. Furthermore, freely moving mice make compensatory eye-movements to hold this region in front of them. Our results indicate that mice have spatial biases in their visual processing, a finding that has important implications for the use of the mouse model of vision.
Highlights
The representation of space in mouse visual cortex was thought to be relatively uniform
To determine whether there might be regions with enhanced spatial resolution in mouse visual cortex, we investigated the representation of space using population receptive field mapping10,11. population receptive-field (pRF) mapping is a forward-modeling technique in which the Gaussian profile that best fits the response of a point in cortex to mapping stimuli is taken as an estimate of the aggregate receptive field (RF) at that point (Supplementary Fig. 1)
We investigated the relationship between the pRF location and size by binning the azimuth and elevation values of all V1 pixels and averaging pRF sizes per bin. pRFs were smallest at azimuths of 0° and at an elevation of 20° above the horizontal plane (Fig. 1f)
Summary
The representation of space in mouse visual cortex was thought to be relatively uniform. We reveal, using population receptive-field (pRF) mapping techniques, that mouse visual cortex contains a region in which pRFs are considerably smaller. This region, the “focea,” represents a location in space in front of, and slightly above, the mouse. Mouse retinas lack a fovea, the region of the retina with greatly enhanced photoreceptor density in comparison to the periphery, and mouse visual cortex does not possess a foveal representation This has implications for the use of the mouse as a model for the human visual system. To determine whether there might be regions with enhanced spatial resolution in mouse visual cortex, we investigated the representation of space using population receptive field (pRF) mapping. Mice had improved spatial resolution in this region of space and freely moving mice made eye movements to compensate for changes in head position to hold the region of smaller pRF size in front of them, slightly above the horizontal plane
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
