Shitova, N. 1, 2 , Roelofs, A. 1 , Coughler, C. 1 & Schriefers , H. 1
1 Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen
2 International Max Planck Research School for Language Sciences, Max Planck Institute for Psycholinguistics Nijmegen
There is some evidence that the allocation and use of processing capacity in spoken language production are reflected in the amplitude of the P300 component. However, little is known about their relation to reaction time (RT) and theta power, which reflects capacity demand outside the language domain. To examine this, we had participants switch every second trial between describing pictures using noun phrases with one adjective (size only; simple condition) or two adjectives (size and colour; complex condition) in the format determiner + adjective(s) + noun. RTs were longer for complex than for simple trials. Moreover, complexity and sequence interacted: RTs were longer on switch than on repeat trials for simple phrases (switch cost) but shorter on switch than on repeat trials for complex phrases (switch benefit), while there was no main effect of sequence. P300 amplitude and theta power increased with complexity. There was no main effect of sequence in electrophysiological measures, but both P300 amplitude and theta power decreased on switch trials as compared to repeat trials for simple phrases. These results provide evidence that the allocation and use of processing capacity in language production are reflected in P300 amplitude and theta power.