Earlier and more robust sensorimotor discrimination of ASL signs in deaf signers during imitation
Quandt, L. C. & Willis, A. S. (2021). Earlier and more robust sensorimotor discrimination of ASL signs in deaf signers during imitation. Language, Cognition, & Neuroscience. DOI: 10.1080/23273798.2021.1925712
Prior research suggests that the amount of experience an individual has with an action influences the degree to which the sensorimotor systems of their brain are involved in the subsequent perception of those actions. Less is known about how action experience and semantic knowledge impact sensorimotor involvement during imitation. To address this question, we collected electroencephalograms (EEG) while deaf signers and hearing non-signers imitated one-handed and two-handed ASL signs. During observation, deaf signers showed early differentiation in alpha/beta power between the one- and two-handed sign conditions, whereas hearing non-signers showed this discrimination only later. During sign imitation, deaf signers showed desynchronisation of alpha/beta EEG signals, while hearing non-signers showed increased power. Thus, in an imitative context, deaf signers engage anticipatory motor preparation in advance of action production, while hearing non-signers engage slower, more memory-related processes to help them complete the complex task.