When "light" and "dark" thoughts become light and dark responses: affect biases brightness judgments.

Metaphors link positive affect to brightness and negative affect to darkness. Research has shown that such mappings are "alive" at encoding in that word-meaning evaluations are faster when font color matches prevailing metaphors (positive = bright; negative = dark). These results, however, involved reaction times, and there are reasons to think that evaluations would be unlikely to influence perceptual judgments, the current focus. Studies 1-3 establish that perceptual judgments were biased in a brighter direction following positive (vs. negative) evaluations, and Study 4 shows that such biases are automatic. The results significantly extend the metaphor representation perspective. Not only do evaluations activate metaphors, but such metaphoric mappings are sufficient to lead individuals to violate input from visual perception when judging an object's brightness.