The role of novel semantic association in the promoting effect of insight on memory

Previous empirical research has found the effect of insight on promoting memory retention during problem solving. Furthermore, neuroimaging studies have revealed that the amygdala, which is assumed to be associated with Aha experience, plays an important role in long-term memory of insightful events. While the emotional Aha experience is a key characteristic of insightful problem solving, some researchers emphasized that the core processes in creating insights involve breaking the mental set and forming novel and valuable associations. However, the cognitive and neural mechanisms underlying the promoting effect of insight on memory have not yet been fully explored. In this study, the paradigm of choice of answers to Chinese Chengyu riddles was adopted to investigate how the process of forming novel associations impacts the effect of insight on promoting subsequent memory. Two experiments were conducted in this study. In Experiment 1, the paradigm of choice of answers to Chinese Chengyu riddles consisted of two phases. In the learning phase, participants were asked to select the novel and suitable answer to the Chengyu riddle from four options; after one week, in the testing phase they were asked to recall the answer that they chose in the learning phase. The novel association and normal association condition were distinguished according to the selections of participants. The paradigm used in Experiment 2 was similar to that of Experiment 1. Additionally, the functional Magnetic Resonance Imaging (fMRI) was used to record the neural activity in the learning phase. The results of Experiment 1 showed that the score of Aha experience in the learning phase and accuracy in the testing phase were significantly higher in the novel association condition compared to the normal association condition. In addition, Experiment 2 showed that the activity in the brain regions related to insight, including the hippocampus, amygdala, middle frontal gyrus, superior temporal gyrus and middle temporal gyrus, were significantly greater in the successful recall compared to the failed recall in novel association condition. Further analysis indicated that successful recall of novel association involved more activity in the right hippocampus compared to the recall of normal association. The current study verified the promoting effect of insight on memory, and indicated that forming novel semantic associations and related activity in the hippocampus may underlie this effect.