title: A common stochastic accumulator with effector-dependent noise can explain eye-hand coordination.
abstract: The computational architecture that enables the flexible coupling between otherwise independent eye and hand effector systems is not understood. By using a drift diffusion framework, in which variability of the reaction time (RT) distribution scales with mean RT, we tested the ability of a common stochastic accumulator to explain eye-hand coordination. Using a combination of behavior, computational modeling and electromyography, we show how a single stochastic accumulator to threshold, followed by noisy effector-dependent delays, explains eye-hand RT distributions and their correlation, while an alternate independent, interactive eye and hand accumulator model does not. Interestingly, the common accumulator model did not explain the RT distributions of the same subjects when they made eye and hand movements in isolation. Taken together, these data suggest that a dedicated circuit underlies coordinated eye-hand planning.
authors.affiliation: National Brain Research Centre, Manesar, Haryana, India; and.
authors.forename: Atul
authors.initials: A
authors.lastname: Gopal
authors.affiliation: National Brain Research Centre, Manesar, Haryana, India; and.
authors.forename: Pooja
authors.initials: P
authors.lastname: Viswanathan
authors.affiliation: Centre for Neuroscience, Indian Institute of Science, Bangalore, Karnataka, India aditya@cns.iisc.ernet.in.
authors.forename: Aditya
authors.initials: A
authors.lastname: Murthy
mesh_terms: D000328:Adult; D005260:Female; D006225:Hand; D006801:Humans; D008297:Male; D010775:Photic Stimulation / Q000379:methods*; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology*; D012438:Saccades / Q000502:physiology*; D013269:Stochastic Processes
keywords: drift diffusion; electromyography; eye-hand coordination; motor preparation; reaction time; variability