GAZE ERROR AND COLOR/NUMBER NAMING FOR SIMULATED BASEBALL PITCHES

Title GAZE ERROR AND COLOR/NUMBER NAMING FOR SIMULATED BASEBALL PITCHES
Author, Co-Author Aaron Zimmerman, Nicklaus Fogt
Topic
Year
2009
Day
Thursday
Program Number
90967
Room
Grand 11-12
Affiliation
The Ohio State University, College of Optometry
Abstract PURPOSE: A suggested exercise for baseball batters is to call out colors and/or numbers written on pitched balls. To evaluate the influence of this color/number naming task on ocular gaze tracking of pitched balls, it is necessary to make measures of eye and head movements during pitches. The purpose of this study was to compare ocular gaze tracking errors for pitched balls in head fixed and head free conditions using a novel tracking method, and to compare the gaze error data to performance in naming colors and numbers on the pitched balls.

METHODS: Novices were shown tennis balls pitched by a pneumatic throwing device at 80mph. Each ball was labeled six times with a red or black number from 0 to 8. Subjects were asked to call out the number and color on each ball. Subjects viewed pitches in two conditions; head fixed (using a chin and forehead rest) and head free (unrestricted). Eye movements, head movements and ball location were recorded and synchronized using a computer program. Gaze error relative to the ball was calculated at 8 feet and 4 feet short of the plate.

RESULTS: Head fixed gaze error at 8 feet short was -3.5 degrees while head free gaze error was -5.7 degrees (p<0.05). Gaze error for the head fixed condition at 4 feet was -11.8 degrees while head free was -13.1 degrees (p>0.10). Condition sequence did not have an effect on performance. Subjects responded correctly to color 61.5% in the head fixed condition and 64.9% in the head free condition; there was no significance (p<0.50). Subjects could not read the numbers;7.8% correct for head fixed and 9.3% correct for head free. There was no correlation between gaze error and color naming.

CONCLUSIONS: For novices, head movement was not beneficial to ocular gaze tracking due to poor suppression of the rotational vestibulo-ocular reflex. The lack of correlation between the color naming task and the gaze errors suggests either that the color naming task does not depend on ocular tracking and target foveation or alternatively color determination is made prior to 8 feet short of the plate.

ADDITIONAL COMMENTS: Funded by Ohio Lions Eye Research Foundation
Affiliation of Co-Authors
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