Persistent directional anisotropy in dynamic visual acuity and attenuated increase in saccadic eye movements with stroboscopic training

Strobe glasses are used for dynamic visual acuity (DVA) training, but evidence is based mainly on horizontal motion. We examined short-term training, stroboscopic training, and directional anisotropy in vertical and horizontal DVA and eye movements. Twenty participants were randomly assigned to strobe or control groups and completed three sessions on alternate days; sixteen were analyzed. DVA improved by 23.4 deg/s per session ( p < 0.001), while vertical DVA remained 36.8 deg/s lower than horizontal DVA ( p < 0.001). The group × session interaction was not significant ( p = 0.252). The saccadic component of the cumulative eye displacement was quantified, with saccade onset and offset defined from the velocity profile and the detected events assessed for consistency with the saccadic main sequence. Saccades accounted for approximately 95% of the cumulative eye displacement. Training increased saccadic displacement, and this increase was attenuated in the strobe group (group × session, $$- 1.82$$ deg per session, p = 0.020). Mean absolute eye–target position error (MAE) decreased by 1.67 deg per session ( p < 0.001) and was 1.45 deg greater for vertical motion ( p = 0.005). The session × group interaction was significant ( $$- 0.92$$ deg per session, p = 0.045), indicating a larger session-related decrease in the strobe group. Thus, short-term practice improved DVA, whereas stroboscopic training was associated with an attenuated session-related increase in saccadic displacement and a larger decrease in MAE, without a significant additional DVA gain. Directional anisotropy remained evident in DVA and eye–target position error.