Correlates of perceptual learning in an oculomotor decision variable

Area of Science:

• Neuroscience
• Cognitive Science
• Perceptual Psychology

Background:

• Neural commands for actions can encode decision-making processes in extensively trained subjects.
• It remains unclear if this representation requires overtraining or reflects a general perceptual-motor link.

Purpose of the Study:

• To investigate how perceptual processing is represented in motor commands in naive monkeys during training on a demanding perceptual task.
• To determine if motor commands reflect decision formation and evidence weighting without extensive training.

Main Methods:

• Monkeys were trained on a random-dot motion perception task requiring a saccadic eye movement to one of two targets.
• Electrically evoked saccades were used to examine oculomotor commands during motion viewing.
• Oculomotor signals and saccadic reaction times were analyzed throughout training.

Main Results:

• Motor commands reflected both the binary choice of saccade target and the weighting of motion evidence.
• Decision-related oculomotor signals and response times changed progressively with training.
• These changes correlated with improvements in behavioral sensitivity to motion stimuli.

Conclusions:

• Motor circuits appear to have general access to perceptual processing for action selection, even without overtraining.
• The findings suggest a mechanism for perceptual learning involving the brain adapting to treat decisions as action selection problems.
• Sensory input effectiveness in guiding action selection improves over time during training.