Faculty Opinions recommendation of A morphological basis for orientation tuning in primary visual cortex.

AbstractPrimary sensory areas of the mammalian neocortex have a remarkable degree of plasticity, allowing neural circuits to adapt to dynamic environments. However, little is known about the effects of traumatic brain injury on visual circuit function. Here we used anatomy and in vivo electrophysiological recordings in adult mice to quantify neuron responses to visual stimuli two weeks and three months after mild controlled cortical impact injury to primary visual cortex (V1). We found that, although V1 remained largely intact in brain-injured mice, there was ~35% reduction in the number of neurons that affected inhibitory cells more broadly than excitatory neurons. V1 neurons showed dramatically reduced activity, impaired responses to visual stimuli and weaker size selectivity and orientation tuning in vivo. Our results show a single, mild contusion injury produces profound and long-lasting impairments in the way V1 neurons encode visual input. These findings provide initial insight into cortical circuit dysfunction following central visual system neurotrauma.

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Temporo-nasally biased moving grating selectivity in mouse primary visual cortex

10.1101/708644 ◽

2019 ◽

Author(s):

Marie Tolkiehn ◽

Simon R. Schultz

Keyword(s):

Visual Cortex ◽

Spatial Frequency ◽

Primary Visual Cortex ◽

Moving Objects ◽

Direction Selectivity ◽

Orientation Tuning ◽

High Signal ◽

Forward Movement ◽

Upward Moving

AbstractOrientation tuning in mouse primary visual cortex (V1) has long been reported to have a random or “salt-and-pepper” organisation, lacking the structure found in cats and primates. Laminar in-vivo multi-electrode array recordings here reveal previously elusive structure in the representation of visual patterns in the mouse visual cortex, with temporo-nasally drifting gratings eliciting consistently highest neuronal responses across cortical layers and columns, whilst upward moving gratings reliably evoked the lowest activities. We suggest this bias in direction selectivity to be behaviourally relevant as objects moving into the visual field from the side or behind may pose a predatory threat to the mouse whereas upward moving objects do not. We found furthermore that direction preference and selectivity was affected by stimulus spatial frequency, and that spatial and directional tuning curves showed high signal correlations decreasing with distance between recording sites. In addition, we show that despite this bias in direction selectivity, it is possible to decode stimulus identity and that spatiotemporal features achieve higher accuracy in the decoding task whereas spike count or population counts are sufficient to decode spatial frequencies implying different encoding strategies.Significance statementWe show that temporo-nasally drifting gratings (i.e. opposite the normal visual flow during forward movement) reliably elicit the highest neural activity in mouse primary visual cortex, whereas upward moving gratings reliably evoke the lowest responses. This encoding may be highly behaviourally relevant, as objects approaching from the periphery may pose a threat (e.g. predators), whereas upward moving objects do not. This is a result at odds with the belief that mouse primary visual cortex is randomly organised. Further to this biased representation, we show that direction tuning depends on the underlying spatial frequency and that tuning preference is spatially correlated both across layers and columns and decreases with cortical distance, providing evidence for structural organisation in mouse primary visual cortex.

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Heterogeneity in local distributions of orientation-selective neurons in the cat primary visual cortex

Visual Neuroscience ◽

10.1017/s095252380000818x ◽

1996 ◽

Vol 13 (3) ◽

pp. 509-516 ◽

Cited By ~ 28

Author(s):

Pedro E. Maldonado ◽

Charles M. Gray

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Local Level ◽

Spike Trains ◽

Preferred Orientation ◽

Orientation Tuning ◽

Area 17 ◽

Average Difference ◽

Orientation Preference ◽

Neuronal Spike Trains

AbstractWe have employed the tetrode technique, which allows accurate discrimination of individual neuronal spike trains from multiunit recordings, in order to examine the variation of orientation selectivity among local groups of neurons. We recorded a total of 321 cells from 62 sites in area 17 of halothane-anesthetized cats; each site contained between three to ten neurons that were estimated to be less than 65 μm away from the tetrode tip. For each cell, we determined the orientation tuning in response to moving bars. Of the cells tested, 8.4% were unresponsive, 22.7% had no preferential response to any particular orientation, while 68.8% were tuned. The average difference in preferred orientation between cell pairs recorded at the same site was 10.7 deg, but the variance in preferred orientation differences differed significantly among sites. Some clusters of cells exhibited the same or nearly the same orientation preference, while others had orientation preferences that differed by as much as 90 deg. Our data demonstrate that the tuning for orientation is more heterogeneously distributed at a local level than previous studies have suggested.

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Orientation Tuning, But Not Direction Selectivity, Is Invariant to Temporal Frequency in Primary Visual Cortex

Journal of Neurophysiology ◽

10.1152/jn.01224.2004 ◽

2005 ◽

Vol 94 (2) ◽

pp. 1336-1345 ◽

Cited By ~ 21

Author(s):

Bartlett D. Moore ◽

Henry J. Alitto ◽

W. Martin Usrey

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Visual Stimulus ◽

Visual Processing ◽

Cortical Neurons ◽

Temporal Frequency ◽

Direction Selectivity ◽

Orientation Tuning ◽

Orientation Contrast ◽

Wide Range

The activity of neurons in primary visual cortex is influenced by the orientation, contrast, and temporal frequency of a visual stimulus. This raises the question of how these stimulus properties interact to shape neuronal responses. While past studies have shown that the bandwidth of orientation tuning is invariant to stimulus contrast, the influence of temporal frequency on orientation-tuning bandwidth is unknown. Here, we investigate the influence of temporal frequency on orientation tuning and direction selectivity in area 17 of ferret visual cortex. For both simple cells and complex cells, measures of orientation-tuning bandwidth (half-width at half-maximum response) are ∼20–25° across a wide range of temporal frequencies. Thus cortical neurons display temporal-frequency invariant orientation tuning. In contrast, direction selectivity is typically reduced, and occasionally reverses, at nonpreferred temporal frequencies. These results show that the mechanisms contributing to the generation of orientation tuning and direction selectivity are differentially affected by the temporal frequency of a visual stimulus and support the notion that stability of orientation tuning is an important aspect of visual processing.

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Orientation tuning for faces in the Fusiform Face Area and Primary Visual Cortex

Journal of Vision ◽

10.1167/12.9.27 ◽

2012 ◽

Vol 12 (9) ◽

pp. 27-27

Author(s):

V. Goffaux ◽

F. Duecker ◽

C. Schiltz ◽

R. Goebel

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Orientation Tuning ◽

Fusiform Face Area ◽

Face Area

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Sub-Optimality of the Early Visual System Explained Through Biologically Plausible Plasticity

Frontiers in Neuroscience ◽

10.3389/fnins.2021.727448 ◽

2021 ◽

Vol 15 ◽

Author(s):

Tushar Chauhan ◽

Timothée Masquelier ◽

Benoit R. Cottereau

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Receptive Fields ◽

Spike Timing ◽

Orientation Tuning ◽

Biologically Relevant ◽

Tuning Curves ◽

Stdp Rule ◽

Early Visual Cortex ◽

Minimisation Problem

The early visual cortex is the site of crucial pre-processing for more complex, biologically relevant computations that drive perception and, ultimately, behaviour. This pre-processing is often studied under the assumption that neural populations are optimised for the most efficient (in terms of energy, information, spikes, etc.) representation of natural statistics. Normative models such as Independent Component Analysis (ICA) and Sparse Coding (SC) consider the phenomenon as a generative, minimisation problem which they assume the early cortical populations have evolved to solve. However, measurements in monkey and cat suggest that receptive fields (RFs) in the primary visual cortex are often noisy, blobby, and symmetrical, making them sub-optimal for operations such as edge-detection. We propose that this suboptimality occurs because the RFs do not emerge through a global minimisation of generative error, but through locally operating biological mechanisms such as spike-timing dependent plasticity (STDP). Using a network endowed with an abstract, rank-based STDP rule, we show that the shape and orientation tuning of the converged units are remarkably close to single-cell measurements in the macaque primary visual cortex. We quantify this similarity using physiological parameters (frequency-normalised spread vectors), information theoretic measures [Kullback–Leibler (KL) divergence and Gini index], as well as simulations of a typical electrophysiology experiment designed to estimate orientation tuning curves. Taken together, our results suggest that compared to purely generative schemes, process-based biophysical models may offer a better description of the suboptimality observed in the early visual cortex.

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