Mouse V1 Neurons Research Articles

Spatiotemporal specificity of contrast adaptation in mouse primary visual cortex

Prolonged viewing of high contrast gratings alters perceived stimulus contrast, and produces characteristic changes in the contrast response functions of neurons in the primary visual cortex (V1). This is referred to as contrast adaptation. Although contrast adaptation has been well-studied, its underlying neural mechanisms are not well-understood. Therefore, we investigated contrast adaptation in mouse V1 with the goal of establishing a quantitative description of this phenomenon in a genetically manipulable animal model. One interesting aspect of contrast adaptation that has been observed both perceptually and in single unit studies is its specificity for the spatial and temporal characteristics of the stimulus. Therefore, in the present work we determined if the magnitude of contrast adaptation in mouse V1 neurons was dependent on the spatial frequency and temporal frequency of the adapting grating. We used protocols that were readily comparable with previous studies in cats and primates, and also a novel contrast ramp stimulus that characterized the spatial and temporal specificity of contrast adaptation simultaneously. Similar to previous work in higher mammals, we found that contrast adaptation was strongest when the spatial frequency and temporal frequency of the adapting grating matched the test stimulus. This suggests similar mechanisms underlying contrast adaptation across animal models and indicates that the rapidly advancing genetic tools available in mice could be used to provide insights into this phenomenon.

Spatiotemporal tuning in mouse primary visual cortex

The neural correlates of visual motion perception have historically been studied in non-human primates. However, the mouse has recently gained popularity as a model for studying vision primarily driven by the hope that the genetic tools available in this species may contribute to our understanding of visual processing in the cortex. A recent calcium-imaging study on the spatiotemporal tuning of mouse striate and extrastriate cortex revealed that neurons in the primary visual cortex (V1) were almost never speed tuned, whereas previous electrophysiological studies in macaques noted around one quarter of V1 neurons appeared to be selective for a particular stimulus speed. We were interested in whether this discrepancy was due to methodological or species differences, so we measured the spatiotemporal tuning of mouse V1 neurons using standard electrophysiological techniques. Using comparable analyses to previous studies of speed tuning, our data showed that speed tuning is rare in mouse V1, which corroborates earlier studies in mouse and points to a species difference in motion processing in early cortex between macaques and other mammals.

Orientation specificity of contrast adaptation in mouse primary visual cortex

Contrast adaptation is a commonly studied phenomenon in vision, where prolonged exposure to spatial contrast alters perceived stimulus contrast and produces characteristic shifts in the contrast response functions of primary visual cortex neurons in cats and primates. In this study we investigated contrast adaptation in mouse primary visual cortex with two goals in mind. First, we sought to establish a quantitative description of contrast adaptation in an animal model, where genetic tools are more readily applicable to this phenomenon. Second, the orientation specificity of contrast adaptation was studied to comparatively assess the possible role of local cortical networks in contrast adaptation. In cats and primates, predictable differences in visual processing across the cortical surface are thought to be caused by inhomogeneous local network membership that arises from the pinwheel organization of orientation columns. Because mice lack this pinwheel organization, we predicted that local cortical networks would have access to a broad spectrum of orientation signals, and contrast adaptation in mice would not be specific to the recorded cell's preferred orientation. We found that most mouse V1 neurons showed contrast adaptation that was robust regardless of whether the adapting stimulus matched the cell's preferred orientation or was orthogonal to it.

Dynamics of spatial frequency tuning in mouse visual cortex

Neuronal spatial frequency tuning in primary visual cortex (V1) substantially changes over time. In both primates and cats, a shift of the neuron's preferred spatial frequency has been observed from low frequencies early in the response to higher frequencies later in the response. In most cases, this shift is accompanied by a decreased tuning bandwidth. Recently, the mouse has gained attention as a suitable animal model to study the basic mechanisms of visual information processing, demonstrating similarities in basic neuronal response properties between rodents and highly visual mammals. Here we report the results of extracellular single-unit recordings in the anesthetized mouse where we analyzed the dynamics of spatial frequency tuning in V1 and the lateromedial area LM within the lateral extrastriate area V2L. We used a reverse-correlation technique to demonstrate that, as in monkeys and cats, the preferred spatial frequency of mouse V1 neurons shifted from low to higher frequencies later in the response. However, this was not correlated with a clear selectivity increase or enhanced suppression of responses to low spatial frequencies. These results suggest that the neuronal connections responsible for the temporal shift in spatial frequency tuning may considerably differ between mice and monkeys.

Generating a diverse repertoire of receptive fields in mouse visual cortex

Event Abstract Back to Event Generating a diverse repertoire of receptive fields in mouse visual cortex Dmitry Tsigankov1, Audrey Sederberg2 and Matthias Kaschube1* 1 Goethe University, Frankfurt Institute for Advanced Studies, Germany 2 University of Chicago, Department of Neurobiology, United States In mouse visual cortex (V1), the receptive fields and responses of neurons are highly diverse [1]. Selectivities for the orientation, direction and visual field location of visual stimuli are arranged nearly randomly across local groups of neurons. In this model study we show that to a very good approximation this organization naturally arises in a very large class of generic random recurrent networks without the need of any stimulus dependent plasticity. We consider a recurrent random network of neurons in V1 layer 4 receiving input from the LGN. Neurons are modeled as firing rate units with a nonlinearity. Assuming the network receives weakly orientation but not direction selective afferent inputs, we show that as a function of average strength of recurrent connections, most neurons increase their orientation selectivity and become also direction selective. For sufficiently strong recurrent connections the distributions of both orientation and direction selectivity closely approaches the experimentally observed distributions in mice [2]. In this regime, neurons show diverse levels of average activity with the majority of cells firing at relatively low rates. Computing the structure of the neurons’ receptive fields we find that they are often composed of several ON- and OFF regions reminiscent of cortical simple cells [1]. We discuss the effect of excitatory and inhibitory connections and the robustness of selectivities with respect to different recurrent connections and visual stimuli. We conclude that a diverse repertoire of receptive fields arises naturally in networks with sufficiently strong recurrent connections. Our results account for the recent observations that neurons in mouse V1 are orientation and direction selective already shortly after the time of eye opening and that dark rearing appears to have little effect on these properties [2]. Acknowledgements Bernstein Focus: Neurotechnology Frankfurt, FKZ 01GQ0840 References [1] Bonin et al., J Neurosc (2011) [2] Rochefort et al., Neuron (2011) Keywords: Dark Rearing, Direction Selectivity, firing rate, Mouse, orientation selectivity, Randomness, Recurrent network Conference: Bernstein Conference 2012, Munich, Germany, 12 Sep - 14 Sep, 2012. Presentation Type: Poster Topic: Sensory processing and perception Citation: Tsigankov D, Sederberg A and Kaschube M (2012). Generating a diverse repertoire of receptive fields in mouse visual cortex. Front. Comput. Neurosci. Conference Abstract: Bernstein Conference 2012. doi: 10.3389/conf.fncom.2012.55.00067 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 19 May 2012; Published Online: 12 Sep 2012. * Correspondence: Prof. Matthias Kaschube, Goethe University, Frankfurt Institute for Advanced Studies, Frankfurt am Main, 60438, Germany, kaschube@fias.uni-frankfurt.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Dmitry Tsigankov Audrey Sederberg Matthias Kaschube Google Dmitry Tsigankov Audrey Sederberg Matthias Kaschube Google Scholar Dmitry Tsigankov Audrey Sederberg Matthias Kaschube PubMed Dmitry Tsigankov Audrey Sederberg Matthias Kaschube Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Functional Specialization of Seven Mouse Visual Cortical Areas

To establish the mouse as a genetically tractable model for high-order visual processing, we characterized fine-scale retinotopic organization of visual cortex and determined functional specialization of layer 2/3 neuronal populations in seven retinotopically identified areas. Each area contains a distinct visuotopic representation and encodes a unique combination of spatiotemporal features. Areas LM, AL, RL, and AM prefer up to three times faster temporal frequencies and significantly lower spatial frequencies than V1, while V1 and PM prefer high spatial and low temporal frequencies. LI prefers both high spatial and temporal frequencies. All extrastriate areas except LI increase orientation selectivity compared to V1, and three areas are significantly more direction selective (AL, RL, and AM). Specific combinations of spatiotemporal representations further distinguish areas. These results reveal that mouse higher visual areas are functionally distinct, and separate groups of areas may be specialized for motion-related versus pattern-related computations, perhaps forming pathways analogous to dorsal and ventral streams in other species.

Orientation Selectivity of Synaptic Input to Neurons in Mouse and Cat Primary Visual Cortex

Primary visual cortex (V1) is the site at which orientation selectivity emerges in mammals: visual thalamus afferents to V1 respond equally to all stimulus orientations, whereas their target V1 neurons respond selectively to stimulus orientation. The emergence of orientation selectivity in V1 has long served as a model for investigating cortical computation. Recent evidence for orientation selectivity in mouse V1 opens cortical computation to dissection by genetic and imaging tools, but also raises two essential questions: (1) How does orientation selectivity in mouse V1 neurons compare with that in previously described species? (2) What is the synaptic basis for orientation selectivity in mouse V1? A comparison of orientation selectivity in mouse and in cat, where such measures have traditionally been made, reveals that orientation selectivity in mouse V1 is weaker than in cat V1, but that spike threshold plays a similar role in narrowing selectivity between membrane potential and spike rate. To uncover the synaptic basis for orientation selectivity, we made whole-cell recordings in vivo from mouse V1 neurons, comparing neuronal input selectivity-based on membrane potential, synaptic excitation, and synaptic inhibition-to output selectivity based on spiking. We found that a neuron's excitatory and inhibitory inputs are selective for the same stimulus orientations as is its membrane potential response, and that inhibitory selectivity is not broader than excitatory selectivity. Inhibition has different dynamics than excitation, adapting more rapidly. In neurons with temporally modulated responses, the timing of excitation and inhibition was different in mice and cats.

Parallel Input Channels to Mouse Primary Visual Cortex

It is generally accepted that in mammals visual information is sent to the brain along functionally specialized parallel pathways, but whether the mouse visual system uses similar processing strategies is not known. It is important to resolve this issue because the mouse brain provides a tractable system for developing a cellular and molecular understanding of disorders affecting spatiotemporal visual processing. We have used single-unit recordings in mouse primary visual cortex to study whether individual neurons are more sensitive to one set of sensory cues than another. Our quantitative analyses show that neurons with short response latencies have low spatial acuity and high sensitivity to contrast, temporal frequency, and speed, whereas neurons with long latencies have high spatial acuity, low sensitivities to contrast, temporal frequency, and speed. These correlations suggest that neurons in mouse V1 receive inputs from a weighted combination of parallel afferent pathways with distinct spatiotemporal sensitivities.

Receptive-field properties of V1 and V2 neurons in mice and macaque monkeys.

We report the results of extracellular single-unit recording experiments where we quantitatively analyzed the receptive-field (RF) properties of neurons in V1 and an adjacent extrastriate visual area (V2L) of anesthetized mice with emphasis on the RF center-surround organization. We compared the results with the RF center-surround organization of V1 and V2 neurons in macaque monkeys. If species differences in spatial scale are taken into consideration, mouse V1 and V2L neurons had remarkably fine stimulus selectivity, and the majority of response properties in V2L were not different from those in V1. The RF center-surround organization of mouse V1 neurons was qualitatively similar to that for macaque monkeys (i.e., the RF center is surrounded by extended suppressive regions). However, unlike in monkey V2, a significant proportion of cortical neurons, largely complex cells in V2L, did not exhibit quantifiable RF surround suppression. Simple cells had smaller RF centers than complex cells, and the prevalence and strength of surround suppression were greater in simple cells than in complex cells. These findings, particularly on the RF center-surround organization of visual cortical neurons, give new insights into the principles governing cortical circuits in the mouse visual cortex and should provide further impetus for the use of mice in studies on the genetic and molecular basis of RF development and synaptic plasticity.

V1 spinal neurons regulate the speed of vertebrate locomotor outputs

The neuronal networks that generate vertebrate movements such as walking and swimming are embedded in the spinal cord. These networks, which are referred to as central pattern generators (CPGs), are ideal systems for determining how ensembles of neurons generate simple behavioural outputs. In spite of efforts to address the organization of the locomotor CPG in walking animals, little is known about the identity and function of the spinal interneuron cell types that contribute to these locomotor networks. Here we use four complementary genetic approaches to directly address the function of mouse V1 neurons, a class of local circuit inhibitory interneurons that selectively express the transcription factor Engrailed1. Our results show that V1 neurons shape motor outputs during locomotion and are required for generating 'fast' motor bursting. These findings outline an important role for inhibition in regulating the frequency of the locomotor CPG rhythm, and also suggest that V1 neurons may have an evolutionarily conserved role in controlling the speed of vertebrate locomotor movements.