Nonuniform surround suppression of visual responses in mouse V1

Area of Science:

• Neuroscience
• Visual Perception
• Computational Neuroscience

Background:

• Complex receptive fields are crucial for perceptual inference in motion and image segmentation.
• End-stopped neurons exhibit suppressed responsiveness when stimuli extend beyond their receptive field center.
• The presence of such receptive field surround properties in mice remains largely uncharacterized.

Purpose of the Study:

• To investigate surround modulation in layer 2/3 neurons of the mouse primary visual cortex.
• To determine if asymmetric receptive field surrounds and diverse modulation patterns exist in mice.
• To assess the correlation between surround asymmetry and orientation selectivity.

Main Methods:

• Utilized two-photon calcium imaging to record neural activity in mouse primary visual cortex.
• Examined surround modulation by presenting visual stimuli to layer 2/3 neurons.
• Quantified the asymmetry and magnitude of surround suppression.

Main Results:

• Significant surround suppression asymmetry was observed in 17% of visually responsive neurons.
• The degree of asymmetry in surround suppression was correlated with orientation selectivity.
• Neurons displayed varied responses, including uniform suppression, end-stopping, and side-stopping.

Conclusions:

• Mouse primary visual cortex neurons exhibit differential sensitivity to surround stimuli.
• Asymmetric and diverse surround modulation are present in mice, similar to other species.
• These findings establish the mouse as a suitable model for studying the neural basis of perceptual inference and surround modulation.