Eye-hand coordination during a double-step task: evidence for a common stochastic accumulator

Gopal, Atul and Murthy, Aditya (2015) Eye-hand coordination during a double-step task: evidence for a common stochastic accumulator. In: JOURNAL OF NEUROPHYSIOLOGY, 114 (3). pp. 1438-1454.

PDF Jou_Neu_114-3_1438_2015.pdf - Published Version Restricted to Registered users only Download (4MB) | Request a copy

Abstract

Many studies of reaching and pointing have shown significant spatial and temporal correlations between eye and hand movements. Nevertheless, it remains unclear whether these correlations are incidental, arising from common inputs (independent model); whether these correlations represent an interaction between otherwise independent eye and hand systems (interactive model); or whether these correlations arise from a single dedicated eye-hand system (common command model). Subjects were instructed to redirect gaze and pointing movements in a double-step task in an attempt to decouple eye-hand movements and causally distinguish between the three architectures. We used a drift-diffusion framework in the context of a race model, which has been previously used to explain redirect behavior for eye and hand movements separately, to predict the pattern of eye-hand decoupling. We found that the common command architecture could best explain the observed frequency of different eye and hand response patterns to the target step. A common stochastic accumulator for eye-hand coordination also predicts comparable variances, despite significant difference in the means of the eye and hand reaction time (RT) distributions, which we tested. Consistent with this prediction, we observed that the variances of the eye and hand RTs were similar, despite much larger hand RTs (similar to 90 ms). Moreover, changes in mean eye RTs, which also increased eye RT variance, produced a similar increase in mean and variance of the associated hand RT. Taken together, these data suggest that a dedicated circuit underlies coordinated eye-hand planning.

Item Type:	Journal Article
Publication:	JOURNAL OF NEUROPHYSIOLOGY
Publisher:	AMER PHYSIOLOGICAL SOC
Additional Information:	Copy right for this article belongs to the AMER PHYSIOLOGICAL SOC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA
Keywords:	drift diffusion; race model; reaction time; eye-hand coordination
Department/Centre:	Division of Biological Sciences > Centre for Neuroscience
Date Deposited:	30 Oct 2015 06:56
Last Modified:	30 Oct 2015 06:56
URI:	http://eprints.iisc.ac.in/id/eprint/52650

Actions (login required)

View Item