Functional Specialization of Mouse Higher Visual Cortical Areas

Abstract

SUMMARY The mouse is emerging as an important model for understanding how sensory neocortex extracts cues to guide behavior, yet little is known about how these cues are processed beyond primary cortical areas. Here, we used two-photon calcium imaging in awake mice to compare visual responses in primary visual cortex (V1) and in two downstream target areas, AL and PM. Neighboring V1 neurons had diverse stimulus preferences spanning five octaves in spatial and temporal frequency. By contrast, AL and PM neurons responded best to distinct ranges of stimulus parameters. Most strikingly, AL neurons preferred fast-moving stimuli while PM neurons preferred slow-moving stimuli. By contrast, neurons in V1, AL, and PM demonstrated similar selectivity for stimulus orientation but not for stimulus direction. Based on these findings, we predict that area AL helps guide behaviors involving fast-moving stimuli (e.g., optic flow), while area PM helps guide behaviors involving slow-moving objects.

Distinct Functional Properties of Primary and Posteromedial Visual Area of Mouse Neocortex

“…Our results for SF and TF tuning are similar to previous reports in V1 (Niell and Stryker, 2008;Gao et al, 2010;Van den Bergh et al, 2010;Andermann et al, 2011;Marshel et al, 2011). Two recent publications have investigated spatiotemporal tuning properties of PM (Andermann et al, 2011;Marshel et al, 2011). Their results parallel our observation of higher SF tuning in PM compared with V1.…”

“…Their results parallel our observation of higher SF tuning in PM compared with V1. It has also been reported that neurons in PM were significantly more tuned for speed than neurons in V1 and also preferred lower peak speeds (Andermann et al, 2011). On the contrary, we find the percentage of speed-tuned neurons to be lower in PM than in V1 and peak speed preferences to be highly overlapping although with a trend toward lower speeds in PM (Figs.…”

Neurofibrillary tangle-bearing neurons are functionally integrated in cortical circuits in vivo

“…The OSI and DSI were calculated as described previously (34). In short, OSI was calculated as the maximum directional response, ΔR max , divided by the sum of responses in all other directions, ΣΔR other (0 ≤ OSI ≤ 1; 1 = perfectly orientation-tuned).…”

“…However, the actual functional properties of NFT-bearing neurons in intact neural circuits have not been explored previously (13). We addressed this question directly using awake in vivo two-photon calcium imaging in a mouse model of NFT formation (rTg4510) by applying recently developed imaging approaches allowing for single-neuron-level and population-level assessment of neural activity in awake mice (14). Because two-photon calcium imaging allows for measurement of response properties in many neurons simultaneously, we were able to directly isolate the impact of NFT deposition in a neuronal microcircuit by evaluating population-level network dynamics and, more specifically, by differentiating the function of individual NFT-bearing and neighboring non-NFT-bearing neurons.…”

The Network for Intracortical Communication in Mouse Visual Cortex

“…But the lesioning techniques used in these studies did not afford the spatial resolution for linking the behavioral deficit unequivocally to specific areas, a problem that will likely be overcome by optogenetic approaches (Lien and Scanziani 2013). Recently, significant progress was made by two-photon imaging of calcium transients in upper layer neurons of multiple areas in mouse visual cortex (Andermann et al 2011;Marshel et al 2011;Roth et al 2012). These recordings showed that tuning to high spatial frequency was more common in LI than in AL, RL and AM, which are more selective for high temporal frequency and the direction of motion.…”