Color illusion as a spatial binding problem

Hybrid motion illusions as examples of perceptual conflict

“…Similar colour changes seem to occur for the motion hybrid images, but might be hard to address with a small number of observers in a laboratory, particularly since there seems to be notable variance across observers. ' Shapiro and Hedjar (2019) have proposed a framework for discussing illusions based on conflicts between possible constructions of reality. As stated in the introduction, the aim is to shift the definition of illusion from 'differences between perception and reality' to 'conflicts between possible constructions of reality'.…”

“…As Shapiro and Hedjar (2019) noted, illusions are always defined by a comparison: a line that looks bent is only an illusion in comparison to another representation in which the line is thought to be straight. Similarly, brightness/lightness displays aren't illusions because identical patches of light look different from each other; they are illusions because the display with mismatched luminance levels stands in contrast to other conditions in which objects don't change brightness when they move in front of a variegated background (Whittle, 2003).…”

“…If, on the other hand, one starts from the ontological position that our perception is a 'controlled hallucination' produced by the brain (Hoffman et al, 2015;Koenderink, 2010;Seth, 2019), then the term illusion is problematic because our perceptions can never be exact copies of reality (see Boring, 1942;Hochberg, 1964;Hoffman, 2019;James, 1890), and all our perceptions are to some extent illusory. Shapiro and Hedjar (2019) proposed a possible way around this ontological conundrum by suggesting that illusions are best understood in terms of perceptual conflicts -an idea that has a long history in the philosophical literature (see Burnyeat, 1981;Westphal, 2005). That is, similar to the controlled hallucination position, what we perceive as reality is the result of a 'reality engine' (Hoffman, 2010) or 'voting process' (Hawkins, 2021) that binds together the To access the movies for this article, please visit the article landing.…”

“…Abstract Shapiro and Hedjar (2019) proposed a shift in the definition of illusion, from 'differences between perception and reality' to 'conflicts between possible constructions of reality'. This paper builds on this idea by presenting a series of motion hybrid images that juxtapose fine scale contrast (high spatial frequency content) with coarse scale contrast-generated motion (low spatial frequency content).…”

“…Illusions arise when the reality engine (or voting process) has difficulty creating a single coherent story of the world, either because it is unable to integrate conflicting neural processes into a single story or because there are multiple perceptual stories that seem incompatible with each other. Shapiro and Hedjar's (2019) intention, then, is to shift the definition of illusion from 'differences between perception and reality' to 'conflicts between possible constructions of reality'. Most of the illusions from my laboratory, and the illusions in this paper, have been generated -intentionally -by creating conflict across stimulus dimensions.…”