The brain uses efference copy information to optimise spatial memory
- PDF / 323,536 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 88 Downloads / 180 Views
RESEARCH ARTICLE
The brain uses efference copy information to optimise spatial memory C. C. Gonzalez • M. R. Burke
Received: 18 May 2012 / Accepted: 3 October 2012 / Published online: 17 October 2012 Springer-Verlag Berlin Heidelberg 2012
Abstract Does a motor response to a target improve the subsequent recall of the target position or can we simply use peripheral position information to guide an accurate response? We suggest that a motor plan of the hand can be enhanced with actual motor and efference copy feedback (GoGo trials), which is absent in the passive observation of a stimulus (NoGo trials). To investigate this effect during eye and hand coordination movements, we presented stimuli in two formats (memory guided or visually guided) under three modality conditions (eyes only, hands only (with eyes fixated), or eyes and hand together). We found that during coordinated movements, both the eye and hand response times were facilitated when efference feedback of the movement was provided. Furthermore, both eye and hand movements to remembered locations were significantly more accurate in the GoGo than in the NoGo trial types. These results reveal that an efference copy of a motor plan enhances memory for a location that is not only observed in eye movements, but also translated downstream into a hand movement. These results have significant implications on how we plan, code and guide behavioural responses, and how we can optimise accuracy and timing to a given target. Keywords Eye–hand coordination Short-term memory Go/NoGo Eye movements Hand movements Vision
C. C. Gonzalez M. R. Burke (&) Faculty of Medicine and Health, Institute of Psychological Sciences, University of Leeds, Leeds LS2 9JT, UK e-mail: [email protected]
Introduction Carrying out every aspect of daily living is mediated by the ability to accurately move through the world. Accurate spatial memory of objects in the world relative to oneself is essential when needing to build a map of the surrounding environment for navigation. This process is done often subconsciously through the use of memory and the oculomotor and motor systems. In order to see and subsequently reach for objects in the environment, we employ a series of saccadic eye movements which typically move the fovea of the eye onto objects of interest. The distance to be moved is calculated by combining information about the retinal distance of the object on the fovea with information about the position of the eye or limb. This informs the brain of the direction and amplitude of the movement to be made. Eye movements can be either reflexive, in response to an external salient stimulus (such as visually guided saccades), or voluntary (internally generate) with the latter making up the majority of eye movements made in everyday life. A tested method of exploring voluntary movements is ‘‘the memory-guided’’ trial type, which involves participants moving their eyes or hand to a previously indicated location (Becker and Fuchs 1969). Classically during these experiments, a
Data Loading...
