Inconsistent findings regarding the valence hypothesis might relate to ambiguously valenced stimuli used in some studies. To account for this potential caveat, we used positive and negative attachment words. A total of 50 participants made lexical decisions in a bilateral simultaneous presentation paradigm. Results showed a general right-visual-field advantage for lexical decisions and a general superiority for positive over negative words. Crucially, we found a left-visual-field advantage for positive over negative words. Results oppose the valence hypothesis, but support a specific role of the right hemisphere in emotional processing, in particular when dealing with positive interpersonal relationship information.