Cancelling Flash Illusory Line Motion by Cancelling the Attentional Gradient and a Consideration of Consciousness

Abstract

Illusory line motion (ILM) refers to the perception of motion in a line that is, in fact, presented in full at one time. One form of this illusion (flashILM) occurs when the line is presented between two objects following a brief luminance change in one of them and flashILM is thought to result from exogenous attention being captured by the flash. Exogenous attention fades with increasing delays, which predicts that flashILM should show a similar temporal pattern. Exogenous attention appears to follow flashILM to become more or less equally distributed along the line.The current study examines flashILM in order to test these predictions derived from the attentional explanation for flashILM and the results were consistent with them. The discussion then concludes with an exploratory analysis approach concerning states of consciousness and decision making and suggests a possible role for attention.

Asymmetrical Pseudo-Extinction Phenomenon in the Illusory Line Motion

“…Several variants of ILM have been proposed in attempting to understand the basic mechanisms underlying its occurrence [6]: (i) if two dots are presented before the appearance of the line and the line is abutting the spots at both of its ends, then observers report a sensation of inward motion that meets at the center of the line [5,7]; (ii) if the bar is presented between two dots (or objects) that differ in some attribute, such as color or shape, then the bar matches one of the objects with respect to this attribute [8,9], in which case it is referred to as transformational apparent motion (TAM); (iii) if the bar appears between two dots, and one of the dots is flashing, then the bar appears to shoot out of the flashed box [2,3,[9][10][11][12], while if the bar is removed following the flash of one dot, then the bar appears to contract into the non-flashed box. Given that in both these latter cases an illusory motion away from the flash is perceived, Han and Hamm [13] named both cases as flash-ILM, suggesting to report as Reverse ILM (RevILM, which is in fact a RevFlashILM), the effect of which, if the bar is removed shortly after the onset of the flash, being that the illusion reverses direction and the bar appears to contract into the flashed box [12,14].…”