The flexibility of association between temporal concepts and physical space in the Japanese language.

Previous studies have indicated that temporal concepts such as the past and future are associated with horizontal (left-right) space. This association has been interpreted as reflecting left-to-right writing systems. The Japanese language, however, is written both horizontally and vertically and, when texts are presented vertically, the sequence of columns runs from right to left. This study examines whether the associations between time and space are changed by the direction of the character strings using a word categorization task. Consistent with previous studies, response times and error rates indicated left-past and right-future associations when participants read words presented horizontally. On the other hand, response times indicated the opposite (i.e., left-future and right-past associations) when participants read words presented vertically. These results suggest that temporal concepts are not associated with one's body or physical space in an inflexible manner, but rather the associations can flexibly change through experience.