Differential Neural Correlates Underlie Judgment of Learning and Subsequent Memory Performance

Abstract

Judgment of learning (JOL) plays a pivotal role in self-regulated learning. Although the JOLs are in general accurate, important deviations from memory performance are often reported, especially when the JOLs are made immediately after learning. Nevertheless, existing studies have not clearly dissociated the neural processes underlying subjective JOL and objective memory. In the present study, participants were asked to study a list of words that would be tested 1 day later. Immediately after learning an item, participants predicted how likely they would remember that item. Critically, the JOL was performed on only half of the studied items to avoid its contamination on subsequent memory. We found that during encoding, compared to items later judged as “will be forgotten,” those judged as “will be remembered” showed stronger activities in the default-mode network, including the ventromedial prefrontal cortex (PFC) and posterior cingulate cortex, as well as weaker functional connectivity between the left dorsolateral PFC and the visual cortex. The exact opposite pattern was found when comparing items that were actually remembered with those that were later forgotten. These important neural dissociations between JOL and memory performance shed light on the neural mechanisms of human metamemory bias.

Individual Differences in the Accuracy of Judgments of Learning Are Related to the Gray Matter Volume and Functional Connectivity of the Left Mid-Insula

“…Contrary to our hypothesis, individual differences in JOL accuracy were not related to the GM volume of medial BA 11, which is activated in the JOL process according to previous task-related fMRI studies ( Kao et al, 2005 ; Do Lam et al, 2012 ; Yang et al, 2015 ). In addition, our results from resting-state fMRI analysis showed that the functional connectivity of medial BA 11 was not correlated with JOL accuracy.…”

“…In particular, we examined the correlation between JOL accuracy and the GM volume of medial BA 11 and the insula. Medial BA 11 is consistently involved in the JOL process ( Kao et al, 2005 ; Do Lam et al, 2012 ; Yang et al, 2015 ) and has been correlated with JOL accuracy in previous task-related fMRI studies (although the direction of the correlation is controversial; see Kao et al, 2005 ; Yang et al, 2015 ). Thus, the GM volume of medial BA 11 may also be correlated with JOL accuracy.…”

“…In addition to lesion-based studies, functional magnetic resonance imaging (MRI) studies have investigated the brain regions underlying the JOL process ( Kao et al, 2005 ; Do Lam et al, 2012 ; Yang et al, 2015 ). An early study by Kao et al (2005) found that the left lateral frontal cortex, left ventromedial prefrontal cortex and several temporal, parietal, occipital and limbic regions were associated with predicted encoding success (i.e., higher activation for high-JOL trials than for low-JOL trials).…”

“…Another study by Do Lam et al (2012) separated JOL trials from initial encoding and indicated that the medial prefrontal cortex, medial orbitofrontal cortex and anterior cingulate cortex were more active during high-JOL trials. In addition, Yang et al (2015) compared the neural activities for encoding trials subsequently given high and low JOLs, and found that the dorsolateral, rostrolateral and ventromedial prefrontal cortex, posterior cingulate cortex, middle temporal gyrus, superior lateral occipital cortex and angular gyrus showed subsequent JOL effects (i.e., higher activation for trials subsequently given high JOLs than those given low JOLs). They also found that greater JOL accuracy was correlated with smaller subsequent JOL effects in the ventromedial prefrontal cortex.…”

“…Although previous studies have investigated the neural correlates of the JOL process from different perspectives, two important issues require further examination. First, although the activation of medial BA 11 has been shown to be consistently associated with the JOL process ( Kao et al, 2005 ; Do Lam et al, 2012 ; Yang et al, 2015 ), no study has examined whether individual differences in JOL accuracy are related to the GM volume of medial BA 11. Second, previous structural MRI studies have not investigated whether JOL is also related to the GM volume of the insula, as found in structural MRI studies concerning FOK ( Cosentino et al, 2015 ; Le Berre et al, 2016 ).…”