弱視および全盲者のナビゲーションにおける残存視線行動

Outdoor navigation poses significant challenges for people with blindness or low vision, yet the role of gaze behaviour in supporting mobility remains underexplored. Fully sighted individuals typically adopt consistent scanning strategies, whereas those with visual impairments rely on heterogeneous adaptations shaped by residual vision and experience.

We conducted a comparative eye-tracking study of fully sighted, low vision, blind, and fully blind participants navigating outdoor routes. Using a wearable eye tracker, we quantified fixation counts, fixation rate, fixation area, direction, peak fixation location, and walking speed.

Walking speed declined systematically with worsening vision. Fixation count increased with greater impairment, reflecting slower travel times and more frequent sampling. Fixation rate differed across groups, though between-group differences were generally not significant between most groups. Fixation spatial coverage decreased along the continuum of vision loss. Fixation patterns were most consistent in the fully sighted group. Peak fixation locations were centred in fully sighted participants but shifted outward and became more variable with impairment.

Gaze strategies during navigation form a graded continuum across vision groups, with fully sighted and fully blind participants at opposite poles and low vision and blind groups spanning the middle. Visual acuity alone does not predict functional gaze use, as rehabilitation experience and adaptive strategies strongly shape behaviour. These findings highlight the need for personalised rehabilitation and assistive technologies, with residual gaze patterns offering insight into mobility capacity and training opportunities for safer navigation.IMPLICATIONS FOR REHABILITATIONDistinct Residual Vision Patterns: This research reveals that residual vision patterns differ significantly, with fully sighted individuals exhibiting a consistent fixation pattern while low vision participants show more varied strategies during navigation.Highly Individualised Gaze Behaviours: Low vision participants demonstrate highly individualised gaze behaviours, indicating that a one-size-fits-all approach is inadequate for effective rehabilitation.Tailored Assistive Solutions: Assistive technologies and rehabilitation programs should be designed to address these unique, individualised needs, providing personalised feedback and training to enhance mobility and safety.