The neural time course of self-oriented pointing and labeling in visual processing
Spencer D Kelly1, Dylan Vlasak1, Binghui Tang1
1Center for Language and Brain, Department of Psychological and Brain Sciences, Colgate University.
Abstract:
Pointing and labeling are traditionally seen as communicative behaviors; the present study examines their neurocognitive consequences when produced for oneself. Twenty-four participants completed a priming task in which they encoded a color prime in three within-subjects conditions: point, label, and point & label. Following each prime, participants judged whether a target object belonged to the same (congruent) or different (incongruent) color category. Target-locked ERPs showed effects of congruence and encoding conditions spanning early and later processing stages. At early latencies, pointing elicited a more positive posterior P1 than labeling, while the combined point & label condition was intermediate and did not differ reliably from either unimodal condition, consistent with a non-additive interaction at early perceptual-attentional stages. At later latencies, pointing alone elicited a larger posterior P2 and smaller central-parietal late negativity (300-500 ms) than labeling alone, and the combined condition diverged from pointing while closely paralleling labeling. Together, these results indicate that pointing and labeling for oneself exert distinct, non-additive influences on downstream object processing, with early processing showing graded interaction and later perceptual and conceptual processing increasingly influenced by labeling.


