Impact of Central Vision Loss on Eye Movements and Time-to-Contact Judgments

Abstract

Age-related macular degeneration (AMD) leads to loss of central vision and typically occurs in older adults. Loss of central vision has been associated with degraded mobility, including difficulties with streetcrossing decisions, which implies that there also may be degraded timeto-contact (TTC) judgments. Further, individuals with AMD have shorter saccades compared to individuals with normal vision leading to difficulty with tracking objects. This study investigated the impact of eye movements on TTC judgments in an AMD group using a predicted motion task in a virtual reality system. Results indicated that longer saccades were associated with more accurate TTC judgments and showed that the AMD group had shorter saccades, and less accurate TTC judgments. As such, difficulties with judgments of collisions in individuals with AMD may result from inefficient eye movements.