Love defies a neat definition because it is a mix of the objective and the subjective, of the biological and social, of the personal and public, and of the conscious and unconscious.
The tools that scientists have to objectively assess love are better than ever before. They are allowing us to understand what is universal and what drives individual variation.
The neuro-chemistry of love is one of the universals, operating without differences based on sex, sexuality, age, or the focus of that love.
Oxytocin and dopamine are critical at the start of any relationship—the latter motivating you to make physical effort and the former orienting that effort toward the new relationship.
…
Individual differences in human love are influenced by a range of factors. Our genotyping work at Oxford University has shown links between neurochemistry and different aspects of our sociability.
Variation in dopamine genes correlates with a person’s involvement at the community level and the number of friends one has; beta-endorphin levels appear to have an association with overall sociability, including empathetic ability and attachment style; and differences in the expression of genes associated with oxytocin and with beta-endorphin seem to fine tune a person’s romantic disposition.
