Coherent encoding of subjective spatial position in visual cortex and hippocampus.

Area of Science:

• Neuroscience
• Computational Neuroscience
• Sensory Processing

Background:

• Vision is crucial for navigation, with interconnected visual and navigational brain systems.
• Previous research suggested spatial position signals emerge early in the visual cortex.

Purpose of the Study:

• To investigate the nature of spatial signals in the primary visual cortex (V1).
• To determine if these signals are modulated by navigational information and subjective position estimates.

Main Methods:

• Recorded neural activity in V1 and hippocampal area CA1 of mice in a virtual reality corridor.
• Utilized identical visual landmarks in different locations to differentiate visual from spatial responses.
• Trained mice to associate specific locations with water rewards to infer subjective position.

Main Results:

• A majority of V1 neurons exhibited spatial modulation, responding differently to identical visual landmarks based on location.
• Neural populations in both V1 and CA1 encoded the animal's position and correlated representation errors.
• Both V1 and CA1 representations better reflected the animal's subjective position (inferred from licking behavior) than its actual location.

Conclusions:

• Visual responses in V1 are significantly influenced by navigational signals.
• These navigational signals in V1 are coherent with hippocampal signals and reflect the animal's subjective spatial awareness.
• The findings suggest navigational information permeates sensory processing from early cortical areas.