Optogenetic stimulation of the primary visual cortex drives activity in the visual association cortex

Area of Science:

• Neuroscience
• Optogenetics
• Primate Research

Background:

• Optogenetic methods are crucial for understanding brain function with high specificity.
• Non-human primates (NHP) are vital models for translational neuroscience.

Purpose of the Study:

• To assess the selectivity of optogenetic stimulation in the macaque monkey primary visual cortex (V1).
• To investigate how V1 stimulation drives local laminar and widespread cortical connectivity related to visual perception.

Main Methods:

• Transfection of dorsal V1 neurons with channelrhodopsin in macaque monkeys.
• fMRI, neurophysiology, and immunohistochemistry to analyze stimulation effects.
• Perceptual decision task to evaluate functional outcomes.

Main Results:

• Optogenetic stimulation of V1 increased activity in visual association areas (V2/V3, V4, MT, FEF).
• Confirmed optogenetic modulation of neural activity and opsin expression, strongest in V1 layer 4-B.
• Stimulation elicited a phosphene percept during a perceptual task in one monkey.

Conclusions:

• Optogenetic methods can effectively drive large-scale primate cortical circuits.
• Demonstrates high functional and spatial specificity for mapping brain networks.
• Highlights the potential for optogenetics in advancing primate neuroscience research.