Prefrontal Cortex Activity When Processing Concrete and Abstract Words: A fNIRS Study

Poster Session B - Sunday, April 14, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Luke Ammazzalorso¹, Ella McCarthy², Jennifer L. Frymiare³; ¹Ursinus College

People process concrete words (e.g., table) faster than abstract words (e.g., peace). The dual-coding theory posits concrete words are stored in a verbal format and a pictorial format (both hemispheres), whereas abstract words are stored only in a verbal format (left hemisphere). Recently, individual differences in mental imagery skill have come to light. One question is whether people with low mental imagery still show an advantage for concrete words and if they also use both hemispheres to access information about concrete words. Twenty-eight participants (68% female, 18-22 years) judged the similarity of concrete words while frontal lobe activity was monitored using functional near-infrared spectroscopy (fNIRS). Participants also completed the Vividness of Visual Imagery Questionnaire (VVIQ) to evaluate the vividness of their mental imagery. Participants were faster when judging concrete words than abstract words, F(1, 27) = 23.67, p < .001. For abstract words, participants judged similar words faster than dissimilar words, t(27) = -3.68, p < .001. Participants also judged similar concrete words to be more similar in meaning than similar abstract words, t(27) = 2.85, p = .008. In inferior prefrontal cortex, oxygenated hemoglobin was lower while rating concrete words than abstract words; however, there was no difference in oxygenated hemoglobin for superior prefrontal cortex, F(1, 26) = 7.46, p = .01. Vividness of mental imagery was not correlated with reaction time or oxygenated hemoglobin levels in the prefrontal cortex (all ps > .10). Mental imagery skills do not appear to affect how people process concrete and abstract words.

Topic Area: LANGUAGE: Semantic