How visual feedback affects movements

by Wu, Sai-Kit

Abstract (Summary)
Monkeys were well trained to perform a variety of point-to-point reaching movements in virtual reality. We systematically varied the timing and location of the visualized hand position to study the way that visual feedback is used during the initial phase of reaching. The results showed that the monkey learned a discrete strategy based on the information from vision of the hand during the reach. This information was used in a different phase of the task after a stereotypic processing delay to reach the target correctly. Here, I demonstrate that reaching movement was affected by a gradual and orderly changed flash distance (at which point the flash was shown), but it was not affected when the order of the flash distance was randomly assigned. This suggested that the flash could not create a clear effect to the reaching every time. Second, I have show that a misplaced location of flash could not make the hand produce the hypothetical adjustment which counterbalanced the perceived error. This suggested that the flash had to contain correct information in order to be used by the monkey. Finally, I showed that the monkey was able to utilize the flash in the spatial rotation center-out task (the flash was displaced to either side of its proper location). This paper provides a novel behavior task for monkeys movement correction experiment, and it is a useful tool to achieve the long-term goals of understanding the connection between M1 neurons and early correction stimulus.
Bibliographical Information:

Advisor:Andrew Schwartz; Tracy Cui; Henry Zeringue; Douglas Weber

School:University of Pittsburgh

School Location:USA - Pennsylvania

Source Type:Master's Thesis



Date of Publication:01/28/2009

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