1983'4, p.104
Mirakian A. I.
Constancy and functional lability of perception

Unlike traditional treatment of the constancy problem the constant/non-constant perception of values is regarded by the author as an immediate-sensual perceptual process consisting of successive microacts, which generate opposite anisotropic relations between compared values. Further transformations of these relations result either in constant or non-constant perception, as well as in perception of depth, of the inter-object distance, etc., - i.e. in the functional lability in perception of spatial relations between objects.