Unique spatial integration in mouse primary visual cortex and higher visual areas

Abstract

Neurons in the visual system integrate over a wide range of spatial scales. This diversity is thought to enable both local and global computations. To understand how spatial information is encoded across the mouse visual system, we use two-photon imaging to measure receptive fields in primary visual cortex (V1) and three downstream higher visual areas (HVAs): LM (lateromedial), AL (anterolateral) and PM (posteromedial). We find significantly larger receptive field sizes and less surround suppression in PM than in V1 or the other HVAs. Unlike other visual features studied in this system, specialization of spatial integration in PM cannot be explained by specific projections from V1 to the HVAs. Instead, our data suggests that distinct connectivity within PM may support the area’s unique ability to encode global features of the visual scene, whereas V1, LM and AL may be more specialized for processing local features.

Mouse higher visual areas provide both distributed and discrete contributions to visually guided behaviors

“…Stimulus contrast, like orientation, robustly modulates neuronal activity across all visual areas [16,17]. To determine which, if any of the three HVAs is required for perception of this broadly represented stimulus feature, we next trained mice on a go/no-go contrast detection task ([30,36]; Figure 4A ).…”

“…First, the monitor was positioned at 45° relative to the body axis, and stimuli were presented at 3 positions (Elevation (El): 10 deg, Azimuth (Az): −10, 10 and 30 deg, 40° sinusoidal gratings, drifting at 2 Hz, 10 s duration, 10 s inter-trial interval) to activate locations in the contralateral visual field ( Figure S1A ). This allowed us to identify sites of retinotopic reversals to define area identity and boundaries [7,16,20]. Next, we positioned the monitor at 0° relative to the body axis, and stimuli were presented at the location used during the behavioral task (El:10, Az: 30-40 deg, green in Figure S1B ).…”

“…However, while there are some sensory stimulus properties that seem to be both functionally and perceptually localized to specific areas [10–12], there are also a number of examples of stimulus properties that have distributed representation across the visual system [13–15]. For instance, in the mouse visual system, the sensitivity of neurons to orientation and contrast is remarkably similar across higher order cortical areas [16–19]. These distributed representations beg the question of which areas are actually responsible for perception of these features.…”

How Cortical Circuits Implement Cortical Computations: Mouse Visual Cortex as a Model

“…Similarly, mouse V1 projects to approximately ten retinotopically organized HVAs (Wang & Burkhalter 2007). Although these HVAs are not arranged in as clear a hierarchy as they are in primates (Nassi & Callaway 2009, Harris et al 2019, they show some degree of specialization for certain properties of visual stimuli (Andermann et al 2011, Glickfeld & Olsen 2017, Juavinett & Callaway 2015, La Chioma et al 2019, Marshel et al 2011, Murgas et al 2020, Roth et al 2012, Sit & Goard 2020. Projections from V1 are often schematized as dedicated pathways, yet among all V1 neurons projecting to HVAs, only 25% target a single HVA, while 60% target two to three HVAs, and 15% target four or more (Han et al 2018).…”

Motion Streak Neurons in the Mouse Visual Cortex

“…The laboratory mouse has become a popular model for studying visual processing over the past decade due to the availability of powerful genetic tools and measurement techniques (Niell and Stryker, 2008;Wang et al, 2010;Glickfeld and Olsen, 2017;Huberman and Niell, 2011;Cang et al, 2018;Hooks and Chen, 2020). A variety of visual stimuli have been used to study mouse visual functions of V1 (Sohya et al, 2007;Niell and Stryker, 2008;Dyballa et al, 2018) and HVAs (Andermann et al, 2011;Marshel et al, 2011;Tohmi et al, 2014;Murakami et al, 2017;La Chioma et al, 2019;Murgas et al, 2020). Recent experiments have used moving dots with an increasing interest in motion processing in mouse visual cortex (Smith et al, 2017;Marques et al, 2018;Dyballa et al, 2018;Sit and Goard, 2020).…”