Investigating the neurophysiological foundations of judgment of learning: An event-related potential study

The ability to monitor the memory and learning processes is crucial for the adaptive behavior. Judgment of Learning (JOL), one of the metacognitive judgments, is commonly used to assess this ability. Different hypotheses have been suggested regarding the cognitive mechanisms underlying this process and its relationship with memory. This study aims to investigate the neural correlates of JOL with event-related potential (ERP) methodology. Seventy-two young adults participated in an episodic memory task involving word-pairs as stimuli. ERP components were compared for distinct JOL levels. Moreover, ERPs for the hit responses in the recognition test were also compared within themselves according to the JOL levels assigned to them. The analyses for the former comparison showed that JOL processes are observable within early time window after stimulus presentation. The P100, N100, P200, N200, and P300 components were found to be elicited for distinct JOL levels, but only N100 did vary in amplitude among those levels. Additionally, a negative component with 330-500 ms latency was also evident for distinct JOL levels and did not differ in amplitude among the levels. The analyses for the recognition phase ERPs showed that different types of hit responses did not show a significant difference in the familiarity-related mid-frontal effect (FN400) amplitude, however those assigned high level of JOL elicited recollection-related parietal old-new effect with smaller amplitude. These results support the hypothesis that JOL is influenced by familiarity and the degree of access to information.