Shared sensory estimates for human motion perception and pursuit eye movements

Area of Science:

• Neuroscience
• Cognitive Science
• Visual Perception

Background:

• The brain's information flow between sensory perception and motor action is not fully understood.
• Investigating shared sensory estimates between perceptual and motor pathways is crucial for understanding brain function.
• The extrastriate visual cortex is involved in both visual motion perception and motor behaviors like smooth pursuit eye movements.

Purpose of the Study:

• To determine if sensory estimates are centrally formed and shared between perceptual and motor pathways.
• To compare perceptual reports with motor behavior derived from the same sensory activity.
• To investigate the role of shared noise sources in perception and action.

Main Methods:

• Analysis of variability in visually driven smooth pursuit eye movements and perceptual reports of motion direction and speed in human subjects.
• Manipulation of signal-to-noise ratio in visual motion estimates.
• Comparison of perception and action variability across different experimental conditions.

Main Results:

• Comparable levels of variability were observed in perception and action pathways, suggesting shared noise sources originating from a common sensory estimate.
• Conditions leading to poor, low-gain smooth pursuit revealed a discrepancy between the precision of perception and that of pursuit.
• Differences in pursuit gain, influenced by optic flow strength, helped reconcile previous controversies regarding sensory information processing.

Conclusions:

• Evidence supports the hypothesis that sensory estimates are centrally represented and shared between perceptual and motor pathways.
• Shared noise sources contribute to variability in both perception and action, highlighting interconnectedness.
• Optic flow strength and resulting pursuit gain play a significant role in modulating the precision of sensory estimates for perception and action.