Desire, love, and attachment are biologically driven by hormones, neurochemicals, neural circuits, and interacting body areas.

“We're going to talk about biological mechanisms such as hormones, biological mechanisms such as neurochemicals, things like dopamine, oxytocin and serotonin, and neural circuits, brain areas, and indeed areas of the body that interact with the brain that control whether or not we desire somebody or not, whether or not we lose or increase our desire for somebody over time, whether or not we fall in love, what love means, and whether or not the relationships we form continue to include the elements of desire and love over time or not.”