Editing Structural information theory (section)

== Visual regularity ==

To obtain simplest codes, SIT applies coding rules that capture the kinds of regularity called iteration, symmetry, and alternation. These have been shown to be the only regularities that satisfy the formal criteria of
(a) being holographic regularities that (b) allow for hierarchically transparent codes.<ref>van der Helm, P. A., & Leeuwenberg, E. L. J. (1991). Accessibility, a criterion for regularity and hierarchy in visual pattern codes. ''Journal of Mathematical Psychology, 35,'' 151—213. {{doi|10.1016/0022-2496(91)90025-O}}.</ref>

A crucial difference with respect to the traditionally considered transformational formalization of visual regularity is that, holographically, mirror symmetry is composed of many relationships between symmetry pairs rather than one relationship between symmetry halves. Whereas the transformational characterization may be suited better for [[object recognition]], the holographic characterization seems more consistent with the buildup of mental representations in object perception.

The perceptual relevance of the criteria of holography and transparency has been verified in the holographic approach to visual regularity.<ref>van der Helm, P. A., & Leeuwenberg, E. L. J. (1996). Goodness of visual regularities: A nontransformational approach. ''Psychological Review, 103,'' 429—456. {{doi|10.1037/0033-295X.103.3.429}}.</ref> It also explains that the detectability of mirror symmetries and Glass pattens in the presence of noise follows a psychophysical law that improves on [[Weber–Fechner law|Weber's law]].<ref>van der Helm, P. A. (2010). Weber-Fechner behaviour in symmetry perception? ''Attention, Perception, & Psychophysics, 72'', 1854—1864. {{doi|10.3758/APP.72.7.1854}}.</ref>