On the Boundaries Between Decision and Action: Effector-Selective Lateralization of Beta-Frequency Power Is Modulated by the Lexical Frequency of Printed Words

Michele Scaltritti , Remo Job , F.-Xavier Alario (1, 2) , Simone Sulpizio

1 ILCB - Institute of Language, Communication and the Brain
2 LPC - Laboratoire de psychologie cognitive

Current computational and neuroscientific models of decision-making posit a discrete, serial processing distinction between upstream decisional stages and downstream processes of motor- response implementation. We investigated this framework in the context of 2-alternative forced- choices on linguistic stimuli, words and pseudo-words. In two experiments, we assessed the impact of lexical frequency and action semantics on two effector-selective EEG indexes of motor-response activation: the lateralized readiness potential and the lateralization of beta- frequency power. This allowed us to track potentially continuous streams of processing progressively mapping the evaluation of linguistic stimuli onto corresponding response channels. Whereas action semantics showed no influence on EEG indexes of motor-response activation, lexical frequency affected the lateralization of response-locked beta-frequency power. We argue that these observations point towards a continuity between linguistic processing of word input stimuli and implementation of corresponding choice in terms of motor behavior. This interpretation challenges the commonly held assumption of a discrete processing distinction between decisional and motor-response processes in the context of decisions based on symbolic stimuli.

Domaines: Sciences cognitives; Psychologie et comportements; Psychologie; Neurobiologie

Michele Scaltritti, Remo Job, F.-Xavier Alario, Simone Sulpizio. On the Boundaries Between Decision and Action: Effector-Selective Lateralization of Beta-Frequency Power Is Modulated by the Lexical Frequency of Printed Words. Journal of Cognitive Neuroscience, inPress. ⟨hal-02883461⟩