The Stream/Bounce Effect with Manual Control of Moving Disks

Abstract

Active control over visual targets has been shown to influence spatial aspects of visual perception (eg, flash lag effect: Ichikawa & Masakura, 2006). We investigated whether or not observers' manual control over target motion affects the pattern of perceptual biases in audio/visual stream/bounce (Sekuler, Sekuler & Lau, 1997) displays. Participants completed four conditions: 1) zero control 2) full manual control over the targets via a concurrent left to right movement of a computer mouse 3) participants thought they were controlling the targets but were not 4) participants moved the mouse to accompany the target motion but were aware this motion was unrelated to the motion on the display. Participants responded “stream” or “bounce” at the end of each sequence when a sound was present or absent when the targets superimposed. Bouncing dominated when a sound was presented in the zero control condition replicated previous stream/bounce studies. The effect was reduced in the remaining conditions, though no s...