Perceptual gloss parameters are encoded by population responses in the monkey inferior temporal cortex

Area of Science:

• Neuroscience
• Visual Perception
• Computational Neuroscience

Background:

• Neurons in the inferior temporal (IT) cortex, specifically the superior temporal sulcus (STS), respond to gloss based on physical reflectance properties.
• Previous research defined a perceptually uniform gloss space using specific axes (c and d).

Purpose of the Study:

• To investigate the relationship between gloss-selective IT neuron activity and perceived gloss.
• To determine if IT neurons represent gloss within a perceptual space.

Main Methods:

• Tested gloss-selective neuron responses to stimuli within a defined perceptual gloss space (c- and d-axes).
• Analyzed neuron activity patterns in relation to perceptual gloss parameters and surface albedo.

Main Results:

• Gloss-selective IT neurons systematically altered responses within the perceptual gloss space.
• Neuron tuning directions were biased towards increasing perceived gloss.
• Population activity of these neurons explained perceptual gloss parameters and surface albedo.

Conclusions:

• The inferior temporal cortex (IT) represents perceptual gloss space.
• Gloss-selective neurons in the STS encode surface properties, contributing to gloss perception.