Perceptually bistable three-dimensional figures evoke high choice probabilities in cortical area MT.

Area of Science:

• Neuroscience
• Computational Neuroscience
• Visual Perception

Background:

• The middle temporal area (MT) is a key region in the primate visual cortex.
• Understanding MT's role in depth perception is essential for visual neuroscience.
• Previous studies suggest MT neurons are involved in motion perception.

Purpose of the Study:

• To investigate the role of middle temporal area (MT) neurons in depth perception.
• To examine the correlation between neuronal activity in MT and subjective depth sensations.
• To determine if MT neurons contribute to perceptual decision-making in depth tasks.

Main Methods:

• Monkeys were trained to report the direction of rotation of a structure-from-motion stimulus.
• Binocular disparities were used to create unambiguous depth cues.
• Trial-to-trial correlations between MT neuronal firing and reported rotation were analyzed using choice probabilities.
• Potential confounds like eye movements and attention were controlled for.

Main Results:

• A significant correlation was found between the firing rate of MT neurons and the reported direction of rotation.
• Choice probabilities indicated that MT neurons are involved in the perceptual decision process for depth.
• The choice probability for the depth task was higher than for a direction discrimination task, suggesting a distinct role for MT.

Conclusions:

• Primate middle temporal area (MT) neurons play a direct role in depth perception and perceptual decision-making.
• The contribution of MT neurons to depth perception differs from their role in motion direction discrimination.
• Findings suggest a smaller neuronal pool or increased neural correlation within MT for depth processing.