Meaningful gestures: Electrophysiological indices of iconic gesture comprehension

TLDR

The study assessed semantic processing of iconic gestures using EEG while participants watched cartoons paired with congruent or incongruent soundless gestures and then responded to probe words. EEG event‑related potentials were recorded from 29 scalp sites across two experiments, where participants judged gesture‑cartoon congruency in Experiment 1 and probe‑word relatedness to preceding gesture‑cartoon pairs in Experiment 2. Gestures elicited a larger N450 component for incongruent than congruent items and a larger late positivity for congruent items in Experiment 1, while Experiment 2 showed N450 effects without positivity, indicating that iconic gestures undergo semantic processing similar to words and pictures.

Abstract

Abstract To assess semantic processing of iconic gestures, EEG (29 scalp sites) was recorded as adults watched cartoon segments paired with soundless videos of congruous and incongruous gestures followed by probe words. Event‐related potentials time‐locked to the onset of gestures and probe words were measured in two experiments. In Experiment 1, participants judged the congruency between gestures and cartoons. Gestures elicited an N400‐like component (gesture N450) that was larger for incongruent than congruent items, as well as a late positivity that was larger for congruent items. In Experiment 2, participants assessed the relatedness between probe words and preceding cartoon‐gesture pairs. N450 effects to gestures were observed without overlapping positivity. These findings suggest that iconic gestures are subject to semantic processes analogous to those evoked by other meaningful representations, such as pictures and words.