Fluctuating internal states mediate neural-behavioral covariations in V1

Area of Science:

• Neuroscience
• Computational Neuroscience
• Systems Neuroscience

Background:

• Perception relies on integrating sensory information with internal brain states.
• The neural mechanisms and brain regions underlying this integration are not fully understood.

Purpose of the Study:

• Investigate how neural activity in the primary visual cortex (V1) relates to behavioral performance.
• Determine the role of internal states in modulating visual processing at the neuronal level.

Main Methods:

• Measured membrane potential (Vm) of single V1 neurons in macaque monkeys during a visual detection task.
• Correlated neuronal activity dynamics with behavioral reaction times and choices.
• Utilized a computational model with fluctuating multiplicative gain to explain observed phenomena.

Main Results:

• Most V1 neurons showed a preparatory depolarization buildup before target onset.
• Variations in this Vm buildup correlated significantly with reaction times.
• Post-target onset Vm fluctuations were linked to behavioral choices, modulated by target location and contrast.
• A computational model successfully replicated these Vm-behavior covariations.

Conclusions:

• Internal states significantly influence neural processing in V1, impacting visual perception and behavior.
• Nonlinear modulations, potentially related to multiplicative gain, in V1 or earlier stages account for Vm-behavior correlations.
• These findings highlight the dynamic interplay between neural activity and internal states in shaping perception.