High neuromagnetic activation in the left prefrontal and frontal cortices correlates with better memory performance for abstract words

Abstract The present study aimed to clarify the spatiotemporal characteristics of memory processing for abstract and concrete words. Neuromagnetic responses to memory encoding and recognition tasks of abstract and concrete nouns were obtained in 18 healthy adults using a whole-head neuromagnetometer. During memory encoding, abstract words elicited larger responses in the left temporal area 300–500 ms after the stimulus onset. The average peak latency of the right inferior frontal and left prefrontal responses to abstract words was about 70–85 ms longer than that to concrete words. Furthermore, greater activation in the left inferior frontal and anterior prefrontal regions was correlated with better recognition memory for abstract words. These findings are consistent with the proposition that both word types are processed with differential integration of semantic information. The present results suggest that the left prefrontal and frontal regions play an important role in both semantic and memory processing for abstract words.