Dopamine, a neurotransmitter in the brain, is more commonly known as the driver in the pleasure center of the brain. This potent neurochemical can increase maternal bonding with a child, sexual attraction to a stranger, preferences for sexual behaviors, satisfaction with one's current relationship, and even duration of one's committed romance. As a whole, current research indicates that dopamine is not just a major player in our relationship behaviors but may in fact be the star player.
Rand, Winston, and Johnson have a small tech startup company in the Bay Area that's developing a artificially-lived computer character, Koy Koy the bird, who can hear and see and interact with the user. Koy Koy gets placed in a kids schoolroom for testing, and Rand develops a relationship with one of the teachers, Sarah. Rand learns that his scientific understanding of human mating isn't necessarily a roadmap for the real thing.