Effects of Lateral Motion on Stereoacuity Thresholds for Physically Moving Targets

The goal of this thesis was to determine the impact of lateral retinal motion on stereoacuity under natural viewing conditions. I found that stereoacuity thresholds remained stable when target velocities varied between 0 and 16 /s. These results do not agree with previous literature (Ramamurthy, Bedell & Patel, 2005) which found that stereoacuity degraded at higher velocities (greater than 3 deg/s). I suggest that depth is acquired very rapidly at target onset when targets are relatively broadband and have not been distorted by motion smear. Subsequent experiments ruled out the potential effects of monocular cues, retinal smear size and inter-stimulus delay enhancing perceived depth. I conclude that artefacts introduced by the graphical displays used by Ramamurthy et al. (2005) were responsible for the observed elevation of thresholds at higher velocities.