Hemispheric asymmetry in the processing of negative and positive words: A divided field study

Abstract

Research on the lateralisation of brain functions for emotion has yielded different results as a function of whether it is the experience, expression, or perceptual processing of emotion that is examined. Further, for the perception of emotion there appear to be differences between the processing of verbal and nonverbal stimuli. The present research examined the hemispheric asymmetry in the processing of verbal stimuli varying in emotional valence. Participants performed a lexical decision task for words varying in affective valence (but equated in terms of arousal) that were presented briefly to the right or left visual field. Participants were significantly faster at recognising positive words presented to the right visual field/left hemisphere. This pattern did not occur for negative words (and was reversed for high arousal negative words). These results suggest that the processing of verbal stimuli varying in emotional valence tends to parallel hemispheric asymmetry in the experience of emotion.

Keywords:

• Hemispheric asymmetry
• Language processing
• Word recognition
• Emotion lateralisation

Notes

¹Other researchers (e.g., Alfano & Cimino, 2008; Atchley et al., 2007) have equated their emotional stimuli in terms of arousal. However, they have used tasks (e.g., trigram identification, valence judgements) other than lexical decision speed and hence examined processes that are substantially different from word recognition.