The right hemisphere fails to orient to the negative valence of visually presented words.

To assess cerebral functional asymmetry for accessing the meaning of emotional words, native English speakers were asked to make lexical decisions to emotional words, neutral words and nonwords briefly flashed in their left or right visual field, that is, perceived by their right or left visual cortex, respectively. Emotionally negative words had an overall probability of occurrence of 12.5% in each visual field and were expected to elicit a P3b event-related potential modulation indexing shifts of attention. Emotionally negative words elicited a P3b when perceived by the left visual cortex but failed to trigger such attention-related response when perceived by the right hemisphere. The results suggest relative insensitivity on the part of the right hemisphere in registering the negative emotional valence of written words.