Illusory upward self-motion results in a decrease in perceived room temperature

Purpose: Stationary observers often experience illusory self-motion (vection) when they are exposed to large patterns of optic flow. The effect of different temperatures on the strength of vection was investigated. Method: Eleven participants were exposed to visual stimuli that induced illusory motion (up, down) in three room temperatures (26°C - 27°C, 21°C - 22°C, 5°C - 6°C). Participants rated (a) the vection magnitude, and (b) the room temperature (twice; before and after vection). Results: Upward vection was rated as stronger than downward vection in the 26°C - 27°C temperature. In addition, after experiencing upward and downward vection, subjective ratings of room temperature decreased and increased, respectively, when the room temperature was 26°C - 27°C. This effect was not observed when the room was 5°C - 6°C. Conclusion: These results suggest that a cross modal association exists between the direction “up” and 26°C - 27°C temperatures