Abstract
Although there have thus far been so many studies of emotion focusing on the specific brain structures such as amygdala, and clinical ones, the neural basis of emotion underlying human nature has not yet been investigated particularly from its adaptive mechanism. Our recent brain imaging studies on the neural basis of maternal love, nostalgic memory and self-esteem provided some important perspectives of human nature. That is, the neural basis of maternal love is based on the integration of dopamine reward system and interoceptive system in the orbitofrontal cortex, suggesting strong mother's mind-body attachment with her own infant. Moreover, nostalgic memory retrieval associated with warm feelings is based on the mutual interaction between dopamine reward system and hippocampal memory system, suggesting its implications for human high adaptability. In addition, the neural mechanism for protection of self-esteem is based on the brain network consisting of memory, cognition and emotion-related areas, consisting with the so-called somatic marker theory. These neural mechanisms are highly essential for the self-preservation and the species-preservation.
