抄録
Metamemory refers to knowledge and monitoring of our own memory. This evaluation can be measured by a judgment of learning (JOL), which is a subjective judgment regarding our confidence in whether a learned item will be remembered in the future. We examined the effects on people's judgments of learning of a different kind of relatedness, which occurs in a list organized into sets of categorically related words and unrelated words. Then, we investigated how metamemory is involved in memory strategy. Furthermore, we examined the hypothesis of neural mechanism that the frontal cortex is critically involved in monitoring and control processes, which are central components of metamemory. Participants were thirteen healthy Japanese adults, and were instructed to memorize a list of words consisted of four exemplars from each of four categories (categorical list condition) or a list of unrelated words (unrelated list condition). The JOLs were made immediately after each learning. During the words learning and JOLs, we also measured oxygenated hemoglobin changes [oxyHb] using the near-infrared spectroscopy (NIRS). The results showed that JOL would be more accurate in the categorical list condition compared with the unrelated list condition, and categorization in memory strategy would be more used in the categorical list condition rather than the unrelated list condition. The results of NIRS showed that [oxyHb] changes in dorsolatere prefrontal area were more increased in the categorical list condition rather than the unrelated list condition, while [oxyHb] changes in medial prefrontal area were more increased in the unrelated list condition rather than the categorical list condition. These findings demonstralte metamemory is involved in an efficient memory strategy and distinct neural mechanisms supporting metamemory processes. It suggests that dorsolateral prefrontal area plays an important role in cognitive control, while medial prefrontal area does it in cognitive monitoring.
