A Role for Mouse Primary Visual Cortex in Motion Perception

• Published in: Current biology 2018-06, Vol.28 (11), p.1703-1713.e6
• Main Authors: Marques, Tiago, Summers, Mathew T., Fioreze, Gabriela, Fridman, Marina, Dias, Rodrigo F., Feller, Marla B., Petreanu, Leopoldo
• Format: Article
• Language: English
• Subjects: behavior; motion vision; two-photon microscopy; visual cortex
• ISSN: 0960-9822; 1879-0445
• DOI: 10.1016/j.cub.2018.04.012

Visual motion is an ethologically important stimulus throughout the animal kingdom. In primates, motion perception relies on specific higher-order cortical regions. Although mouse primary visual cortex (V1) and higher-order visual areas show direction-selective (DS) responses, their role in motion perception remains unknown. Here, we tested whether V1 is involved in motion perception in mice. We developed a head-fixed discrimination task in which mice must report their perceived direction of motion from random dot kinematograms (RDKs). After training, mice made around 90% correct choices for stimuli with high coherence and performed significantly above chance for 16% coherent RDKs. Accuracy increased with both stimulus duration and visual field coverage of the stimulus, suggesting that mice in this task integrate motion information in time and space. Retinal recordings showed that thalamically projecting On-Off DS ganglion cells display DS responses when stimulated with RDKs. Two-photon calcium imaging revealed that neurons in layer (L) 2/3 of V1 display strong DS tuning in response to this stimulus. Thus, RDKs engage motion-sensitive retinal circuits as well as downstream visual cortical areas. Contralateral V1 activity played a key role in this motion direction discrimination task because its reversible inactivation with muscimol led to a significant reduction in performance. Neurometric-psychometric comparisons showed that an ideal observer could solve the task with the information encoded in DS L2/3 neurons. Motion discrimination of RDKs presents a powerful behavioral tool for dissecting the role of retino-forebrain circuits in motion processing. •Mice discriminate direction of motion from RDKs in a head-fixed task•Mice solve the task by integrating motion information in time and space•RDKs elicit direction-selective responses in V1 neurons and On-Off DSGCs•Motion perception requires a functioning V1 Using a head-fixed task, Marques et al. show that mice can discriminate the direction of motion of random dot kinetogram stimuli (RDK). RDKs elicit direction-selective responses in both On-Off DSGCs of the retina and in V1 L2/3 neurons. V1 inactivation impairs task performance, showing that this area plays a key role in motion perception.