Background: Current studies revealed the importance of perceptual training for the treatment of amblyopia. To improve stereo vision on a higher level, visual tasks have to be completed within a limited time window like in repetitive visual function tests. "Processing time" as the reaction time in which the absence or presence of depth was identified correctly, is of better predictive value for perceiving the depth than the stereo threshold only.
Objective: To examine the long-term effects of repetitive dynamic testing of stereopsis on processing time.
Methods: 15 male soccer athletes (13.3±3.2 years) underwent twelve sessions of a 15 minutes repetitive dynamic stereovision training over a period of six weeks, presented on a polarized 3D-TV in a four-alternative forced choice setup. We measured the response time of correct identified visual tasks of 11, 22, 44, 55, 66, 77 and 88arcsecs disparity before, after six sessions, after twelve sessions and after six month without testing. As response time is the sum of stereo processing time plus the motor reaction time, we defined the difference between the response times at 11 and 88arcsecs as "stereo processing time at 11arcsecs". A Wilcoxon Signed Rank Test was conducted between the testing sessions to evaluate significant changes in response time and stereo processing time.
Results: After six sessions the mean stereo processing time at 11arcsecs decreased significantly from 804.4 ms to 403.7 ms (Z = -2.499, p = 0.012). Six months after the last training the stereo processing time at 11arcsecs remained at the level of the last session.
Conclusion: Our results suggest that repetitive testing of stereovision is effective in improving processing time of stereoscopic tasks in young male athletes significantly long-term.
Keywords: Binocular vision; depth; depth perception; detection/discrimination; learning; plasticity; stereo acuity; stereopsis.