Right is it right? Influence of the type of motor response on behavioral and electrophysiological indicators during the orthographic decision task

Abstract

The role of the sensorimotor component in the processing of verbal information is currently widely discussed. We hypothesize that the type of motor response may influence behavioral and electrophysiological performance in an orthographic decision task. Event-related potentials (ERPs) were recorded in 42 right-handers during an orthographic decision task. Half of the participants were instructed to press the right button with their right hand upon encountering correctly spelled words and the left button with their left hand upon encountering misspelled words, while the other half followed the opposite instruction. The motor response to correctly spelled words was shorter for the dominant hand compared to the non-dominant hand, which may be due to the coincidence of semantic and motor representations (stimulus-response compatibility effect). In addition, reaction times to incorrectly spelled words were longer than to correctly spelled words only in the group of participants who responded with their dominant hand to correctly spelled words. The P200 and N400 ERP components did not depend on the type of motor response. However, in the group of participants who pressed correctly spelled words with their right hand, the amplitude of the P600 component was greater for misspelled words compared to correctly spelled words. Thus, the type of motor response influenced the effects associated with word spelling recognition.