Allocation of Visuospatial Attention Indexes Evidence Accumulation for Reach Decisions

Area of Science:

• Cognitive Neuroscience
• Sensorimotor Control
• Decision Science

Background:

• Visuospatial attention enhances performance for visually guided movements.
• Attentional prioritization evolves during motor preparation, but its link to movement decisions is unclear.

Purpose of the Study:

• To investigate whether attention build-up reflects attention formation time or the emergence of a movement decision.
• To characterize the temporal dynamics of attention allocation during motor preparation.

Main Methods:

• Combined behavioral experiments, psychophysics, and computational decision-making models.
• Participants performed center-out reaches and a concurrent visual discrimination task.
• Analyzed the time course of visual discrimination at potential target locations.

Main Results:

• Visual discrimination increased at both potential target locations, modulated by goal probability.
• Attention further increased for the chosen goal location, correlating with movement initiation.
• A sequential sampling model accurately predicted attentional allocation timing.

Conclusions:

• Attention build-up during motor preparation indexes a time-extended, cumulative decision process.
• This process links perceptual and motor aspects of sensorimotor decisions.
• Attentional prioritization is not merely a spatial selection but reflects decision dynamics.