Emotion modulates language production during covert picture naming

Previous studies have shown that emotional content modulates the activity of several components of the event-related potentials during word comprehension. However, little is known about the impact of affective information on the different processing stages involved in word production. In the present study we aimed to investigate the influence of positive and negative emotions in phonological encoding, a process that have been shown to take place between 300 and 450 ms in previous studies. Participants performed letter searching in a picture naming task. It was found that grapheme monitoring in positive and negative picture names was associated with slower reaction times and enhanced amplitudes of a positive component around 400 ms as compared to monitoring letters in neutral picture names. We propose that this modulation reflects a disruption in phonological encoding processes as a consequence of the capture of attention by affective content. Grapheme monitoring in positive picture names also elicited higher amplitudes than letter searching in neutral image names in a positive component around 100 ms. This amplitude enhancement might be interpreted as a manifestation of the 'positive offset' during conceptual preparation processes. The results of a control experiment with a passive viewing task showed that both effects cannot be simply attributed to the processing of the emotional images per se. Overall, it seems that emotion modulates word production at several processing stages.