Reading-related habitual eye movements produce a directional anisotropy in the perception of speed and animacy.

Judgments of speed and animacy from monolingual English readers were compared with those of bilingual readers of both English and a language read from right to left. Participants viewed a pair of dots moving horizontally across a screen at the same speed. Using a two-alternative forced-choice task, participants judged which dot in a pair moved faster (a direct measure of speed perception) or appeared to be alive (an indirect and correlated judgment of speed perception). In two experiments monolingual participants judged dots moving left to right to be faster and alive more often than dots moving right to left. In contrast, bilingual participants exhibited no directional bias for speed or animacy. These results suggest that the highly practiced eye movements involved in reading are associated with the presence or absence of a directional anisotropy for speed and animacy.