Mouse visual cortex contains a region of enhanced spatial resolution

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.

Population receptive fields in nonhuman primates from whole-brain fMRI and large-scale neurophysiology in visual cortex

“…RFs ( Hartline, 1938 ; Sherrington, 1906 ) typically describe stimulus locations that evoke or modulate neuronal responses, but they can be generalized to different stimulus features such as color or spatial frequency. RFs are usually measured by determining the neuronal firing rate elicited by visual stimuli ( Hubel and Wiesel, 1998 ; Hubel and Wiesel, 1968 ; Hubel and Wiesel, 1959 ), but they can also be defined based on other neuronal signals such as subthreshold activity ( Priebe, 2008 ), properties of the local field potential (LFP; Victor et al, 1994 ), or calcium levels that can, for instance, be measured with fluorescent calcium indicators ( van Beest et al, 2021 ; Bonin et al, 2011 ).…”

Different patterns of visual processing for shapes in V1 of mouse and monkey

“…Figure 1E shows that the top corners evoked significantly smaller responses (in the posterior part of V1) than the responses evoked by bottom corners (in the anterior part of V1) for all percentile thresholds (mean±1SEM mm 2 , n=25; 60%: 0.62±0.03, 0.79±0.05 for top and bottom respectively; 70%: 0.48±0.02, 0.64±0.04 for top and bottom respectively; 80%: 0.35±0.02, 0.48±0.03 for top and bottom respectively; 90%: 0.20±0.011, 0.28±0.02 for top and bottom respectively; Wilcoxon rank sum test, p<0.005). Additionally, and in accordance with previous reports, the activation patches for the corner stimuli showed an anisotropic spread along the anterior-posterior axis (Schuett, Bonhoeffer and Hübener, 2002; Garrett et al ., 2014; Ji et al ., 2015b; van Beest et al ., 2021). In summary, using the corner stimuli we mapped the shape contours onto V1 and found that the point-spread function (PSF) is larger in the anterior part of V1.…”

“…1E). In addition, and in accordance with previous studies, we found anisotropy of the visual responses along the anterior-posterior axis (Schuett, Bonhoeffer and Hübener, 2002; Garrett et al ., 2014; Ji et al ., 2015b; van Beest et al ., 2021). How can inhomogeneous cortical representation meet the ecological requirements of mice living in natural enviroment?…”

Superior colliculus drives stimulus-evoked directionally biased saccades and attempted head movements in head-fixed mice

“…As natural stimuli are often multimodal, directing non-visual stimuli toward the center of view maximizes the likelihood of detecting the visual component of the stimulus. Alternatively, despite mouse retinae lacking discrete, anatomically defined specializations such as foveae or areas centralis, there are subtler nonuniformities in the distribution and density of photoreceptors and retinal ganglion cell subtypes, and magnification factor, receptive field sizes, and response tuning vary across the visual field in higher visual centers; it may be desirable to center a salient tactile stimulus on a particular retinal region ( Ahmadlou and Heimel, 2015 ; Baden et al, 2013 ; van Beest et al, 2021 ; Bleckert et al, 2014 ; Dräger and Hubel, 1976 ; Feinberg and Meister, 2015 ; Li et al, 2020 ; de Malmazet et al, 2018 ). Although touch-evoked saccades alone may be too small to center the stimulus location on any particular region of the retina, they may do so in concert with directed head movements.…”