Additional evidence is presented concerning the anisotropy between vertical and horizontal encoding, which emerges from studies of human perception and cognition of space in plane mirror reflections. Moreover, it is suggested that the non-metric characteristic of polarization is not limited to the vertical dimension.

In §1, the bona fide anisotropy of physical time is sharply distinguished from the alleged one-way flow of time.

The concept of an objective spatial direction in special relativity is investigated and theories assuming light-speed isotropy while accepting the existence of a privileged spatial direction are classified, including so-called very special relativity. A natural generalization of the proper time principle is introduced which makes it possible to devise non-optical experimental tests of spatial isotropy. Several common misunderstandings in the relativistic literature concerning the role of spatial isotropy are clarified.

A meta-analysis and an experiment show that the degree of compression of the in-depth dimension of visual space relative to the frontal dimension increases quickly as a function of the distance between the stimulus and the observer at first, but the rate of change slows beyond 7 m from the observer, reaching an apparent asymptote of about 50 %. In addition, the compression of visual space is greater for monocular and reduced cue conditions. The pattern of compression of the in-depth (...) dimension as a function of distance is similar to the ratio of in-depth to frontal visual angles of stimuli, but is not as extreme as this ratio would suggest, implying that observers are incapable of fully ignoring size information provided by cues to depth. Size and distance judgments may be described by an Affine transformation of physical space; however, the compression parameter in this model changes as a function of distance from the observer and other experimental conditions. (shrink)

Cultural forms are constrained by cognitive biases, and writing is thought to have evolved to fit basic visual preferences, but little is known about the history and mechanisms of that evolution. Cognitive constraints have been documented for the topology of script features, but not for their orientation. Orientation anisotropy in human vision, as revealed by the oblique effect, suggests that cardinal orientations, being easier to process, should be overrepresented in letters. As this study of 116 scripts shows, the orientation (...) of strokes inside written characters massively favors cardinal directions, and it is organized in such a way as to make letter recognition easier: Cardinal and oblique strokes tend not to mix, and mirror symmetry is anisotropic, favoring vertical over horizontal symmetry. Phylogenetic analyses and recently invented scripts show that cultural evolution over the last three millennia cannot be the sole cause of these effects. (shrink)

Riemer’s recent paper on the perception of time discusses a neglected yet important topic in the psychological literature: the consequences for psychology (and psychophysics) from the ‘anisotropy’ of time. The paper presents an argument that there are unique kinds of challenges for psychophysics from such temporal anisotropy: (a) Challenges because the psychological experience of time has temporal anisotropy and the physical concept of time does not have temporal anisotropy. (b) Challenges for experimental research which are unique (...) to temporal anisotropy. -/- Although it is important to consider temporal anisotropy, I think there are reasons to deny the force of both kinds of challenges. (shrink)