Toddlers show sensorimotor activity during auditory verb processing.

Language that describes actions, for instance verbs, can help to predict future actions of conspecifics in social interactions. Language and action are therefore interrelated. This interrelation has been described on a behavioral level for adults and toddlers. Furthermore, in adults, the sensorimotor system is involved in this interrelation. However, little is known about the early interrelation on the neural level at the onset of verb acquisition. In the present study, we examined the role of the sensorimotor system during the processing of acoustically presented verbs that describe dynamic actions and visually presented actions in toddlers, who are in the earliest stage of expressive language development. The activity of the sensorimotor system, in particular the suppression of the mu rhythm, was measured by means of electroencephalography (EEG). Results showed a significant suppression of the mu rhythm during both the processing of action verbs and observed actions, but not during the processing of pseudoverbs. This suggests that the sensorimotor system is already involved in the processing of action and language early in life.