Mate choice is one of the most significant decisions in daily life. Human neuroimaging studies have shown that passionate love is accompanied by activation of the reward system, a neural basis believed to be shared with other animal species that practice monogamous relationships. Although it is widely accepted that the reward system plays a crucial role in maintaining romantic bonds, one critical question about human mate choice remains unanswered: “How is selective preference for a significant other formed in our brain?” The key to answering this lies in understanding how facial attractiveness is integrated into romantic interest and how it is modified. This paper reviews findings from human neuroimaging studies on romantic relationships and neurobiological studies of non-human animal species that exhibit monogamous relationships. It also proposes possible approaches to these issues based on a recently proposed theoretical model of attachment bonds. A comprehensive understanding of the cognitive and neural mechanisms underlying the formation of a selective preference for a significant other is expected to resolve the fundamental question: “How do we choose a romantic partner?”
