How does V1 population activity inform perceptual certainty?

Area of Science:

• Neuroscience
• Computational Neuroscience
• Sensory Processing

Background:

• Neural population activity in the sensory cortex is crucial for perceptual interpretation.
• This activity can support multiple interpretations, with probability spread indicating uncertainty.
• Understanding how the brain represents perceptual certainty is a key challenge.

Purpose of the Study:

• To test if simple transformations of sensory population activity can reveal the reliability of perceptual interpretations.
• To investigate the relationship between V1 population activity and orientation certainty.
• To identify neural correlates of perceptual uncertainty.

Main Methods:

• Recorded V1 population activity in macaques viewing oriented stimuli.
• Manipulated stimulus signal strength and nuisance variability.
• Developed a decoding procedure to estimate stimulus orientation and certainty from V1 activity.

Main Results:

• Response magnitude, response dispersion, and response gain variability were identified as proxies for orientation certainty.
• Variability in response gain showed the strongest association with decoder uncertainty estimates.
• These neural metrics provide information about the reliability of perceptual estimates.

Conclusions:

• Neural population activity in V1 contains signals that reflect the certainty of perceptual interpretations.
• Response gain variability is a particularly strong indicator of uncertainty.
• These findings suggest that sensory cortex provides downstream circuits with information to assess perceptual reliability.