Functional Neuroimaging Investigation of the Neural Mechanisms for Successful Feeling-of-Knowing Judgments

Abstract

A feeling-of-knowing (FOK) is a sense of knowing that an item would be recognizable if seen again later, despite one’s current inability to recall that item from memory. An FOK judgment occurs after a memory search and is a prediction of future recognition. The current study aimed to: (1) determine the brain regions involved in successful (accurate) and unsuccessful (inaccurate) episodic FOKs; (2) replicate the ability of FOKs to predict recognition outcomes and recollection/know (R/K) judgments; (3) explore the different effects of familiarity and recollection on high and low FOKs; and (4) determine the effect of overlearning on FOKs and their ability to predict recognition and R/K outcomes. Nine younger adults (ages 18-26) participated in 2 experimental sessions (encoding and testing), separated by a 48-hour delay (n = 4 for fMRI data). The amount of exposure to the studied items (1 versus 3 presentations) was manipulated. Statistically significant results include (1) a repetition effect such that the words that were repeated during encoding have higher mean recall, mean FOK rating, mean recognition accuracy, and mean R/K than those words presented only once; (2) activity in the ventral lateral prefrontal cortex (PFC) for successful or accurate FOKs; (3) activity in the anterior PFC for accurate high FOKs; and (4) activity in the PFC and anterior cingulate for correctly recognized and remembered items. In future, additional participants are necessary to conduct further and more detailed analyses.Hertzog, Chris - Faculty Mentor ; Schumacher, Eric - Committee Member/Second Reade