THE EFFECT OF INDUCED BLUR ON GAZE TRACKING FOR A PREDICTABLE TARGET

Title THE EFFECT OF INDUCED BLUR ON GAZE TRACKING FOR A PREDICTABLE TARGET
Author, Co-Author Aaron Zimmerman, Kimberly Lust, Mark Bullimore, Nicklaus Fogt
Topic
Year
2011
Day
Program Number
115268
Room
Amphitheater
Affiliation
The Ohio State University, College of Optometry
Abstract PURPOSE: Baseball hitters have stated that it is possible to pick up visual cues, such as the pitcher’s arm position and ball rotation as it relates to pitch type. A study has also shown that a professional baseball player has superior tracking abilities to controls. This study determined the effect of blur on one’s ability to track a predictable simulated baseball pitch.

METHODS: Ten subjects with varying baseball experience were artificially blurred with soft contact lenses, in a randomized fashion, using the following powers relative to their habitual refractive error: plano, +1.00, +2.00, and +3.00 D. Monocular visual acuities were assessed for each level of blur using a Bailey-Lovie chart. Synchronized head and eye tracking equipment were placed on the subjects who were then told to track tennis balls from a pitching machine without attempting to hit. Twenty pitches were recorded for each blur condition and the change in head position, eye position, and overall gaze error for multiple positions of the pitch trajectory were recorded.

RESULTS: At 150 and 200ms into the pitch trajectory the +2.00 D condition yielded significantly larger head movements (p < 0.0001) and significantly smaller eye movement s (p = 0.017) than the other conditions, yet there was no significant difference in gaze error. At 300 and 305ms into the pitch, the +1.00 D condition had a significantly lower gaze error (p = 0.001), nearly 3 degrees better than the other three conditions, and was associated with lower amplitude head and eye movements.


CONCLUSIONS: The +1.00 D condition was associated with a lower gaze error as the ball approached a position 10 feet short of the plate. However, there was no difference in gaze error for any condition earlier in the trajectory, where blur would be suspected to be most detrimental to performance. Significant blur did not have an effect on gaze tracking for a predictable trajectory. Blur might be more likely to effect gaze for unpredictable trajectories such as those encountered in a game situation.
Affiliation of Co-Authors The Ohio State University, College of Optometry, The Ohio State University, College of Optometry, The Ohio State University, College of Optometry
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