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Vertical vergence adaptation does improve with practice.

Nisha Patel·Alison Y Firth
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Abstract

PURPOSE: To investigate the effect of repeated testing on adaptation to a 2 Delta vertical prism in subjects with normal binocular single vision. METHODS: Subjects were required to have good visual acuity and normal binocular single vision. The residual deviation was measured after a 1-min period of adaptation to a 2 Delta vertical prism using a modified Maddox Rod technique. This measurement was repeated 10 times, with a 5-min rest period between each trial. RESULTS: For eight young adult subjects, the mean residual deviation at 1 min reduced with consecutive trials, and this effect was statistically significant (p < 0.0001). No significant correlation was present between the amplitude of vertical vergence and the increase in adaptation with repeated demand. CONCLUSIONS: A practice effect for vertical vergence adaptation appears to be present in young adult subjects with normal binocular single vision.

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Adaptation, OcularAdolescentAdultConvergence, OcularHumansLearningVision DisparityVision, BinocularJournal Article

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Nisha Patel, Alison Y Firth. 2003. Vertical vergence adaptation does improve with practice.. https://doi.org/10.1097/00006324-200304000-00010

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