The influence of visual mental imagery size on metamemory accuracy in judgment of learning.

Many studies have found the font size of to-be-remembered words has a significant influence on judgments of learning (JOLs). However, few studies have investigated whether JOLs are affected by the mental imagery size of to-be-remembered words, even when the font sizes themselves are kept identical in study materials. This study investigated whether the visual mental imagery size influences the participants' JOLs and what the underlying mechanisms are. In Experiments 1 and 2, participants learned words with identical font sizes, mentally generated large or small imageries and then made JOLs. We found that JOLs under the large imagery condition were significantly higher than those under the small imagery condition, but actual recall performance exhibited no significant difference. In Experiment 3, participants pressed a button immediately after mental imagery generation and showed that it took significantly longer to generate large imageries than to generate small imageries, and the difference in JOLs between two conditions was no longer significant. In Experiment 4, we used a questionnaire to investigate the contribution of beliefs and found that participants believed large imageries were easier to remember. These findings indicate that imagery size has a significant impact on JOLs, in which beliefs may play a leading role.