Date of Award
Master of Science in Vision Science
Twenty players from Pacific University's baseball team were tested on the Pacific Sports Vision Performance Profile (PSVPP) to determine if phoria and fixation disparity, as measured by the PSVPP, correlates to actual hitting tendencies. PSVPP results indicate that a statistically significant correlation exists between actual batting placement and phorias indicated by the PSVPP (pe0.001). Those exophoric players who bat right handed tend to hit to left field, orthophores tend to hit to centerfield, and esophores tend to hit to right field. The reverse is true for left and right field placement for left handed hitters. Furthermore, a trend was also noted in the phorias and fixation disparities of starters ('first string' players) vs. non-starters in that the starter's values were found to be closer to orthophoric. This suggests that as one moves up the ranks in baseball, those athletes who perform the best may be likely to have or develop a low or zero phoria and fixation disparity. It also points to the possibility that hitting placement may be affected by phoria compensation using prism.
Beisiegel, David and Copeland, Alan, "The effect of phoria and fixation disparity on the hitting placement of baseball players" (2004). College of Optometry. 1465.