Sean Green, Cognitive Psychology, UB:

"The simultaneous influence of multiple factors on Illusory Line Motion (ILM)"

Illusory Line Motion (ILM) refers to motion within an appearing or disappearing probe line due to the presence of a nearby priming object. In Forward-ILM, motion is within an appearing probe line away from a previously presented priming object. Reverse-ILM refers to motion within a disappearing probe line toward a priming object.
The present study employed stimuli in which both Forward and Reverse ILM affect the perception of a color change within a probe line. We independently manipulated three factors ? primer luminance, time of primer appearance and time of primer disappearance ? which in isolation strengthen or weaken these illusions. The aim of this experiment was to determine whether Forward and Reverse ILM contributions to overall illusory motion are additive or whether their relationship is more complex. This has implications for whether ILM can be explained as a cognitive inference or by mechanistic changes in the speed at which visual information is processed.
Effects of Reverse ILM did not change significantly despite changes in primer-probe similarity or differences in the strength of the Forward ILM component. A significant effect of primer disappea rance was found in conditions that elicited no net Forward ILM as well as those that elicited strong Forward ILM. This suggests that Forward and Reverse ILM are additive, independent effects and not due to cognitive inference.

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