Biology of romantic love
Specific chemical substances such as oxytocin and dopamine are studied in the context of their roles in producing human experiences, emotions and behaviors that are associated with romantic love.
It occurs across the lifespan and is associated with distinctive cognitive, emotional, behavioral, social, genetic, neural, and endocrine activity in both sexes.
[2][5][3] Courtship attraction is a phenomenon exhibited by many species which serves the role of mate choice, or intersexual selection.
[6] This refers to physical and behavioral characteristics, as well as brain systems which motivate an individual to pursue a preferred mating partner.
[6] Courtship attraction shares similar behaviors with romantic love in humans, and both involve activation of dopaminergic reward circuits.
[9][3] Leckman & Mayes speculate that there is an evolutionary reason behind the similarity, asking "If some part of the behavioral repertoire works in one context to help create and sustain a relationship, why not borrow it to form another?
Another is that sexually transmitted diseases may cause, among other effects, permanently reduced fertility, injury to the fetus, and increase risks during childbirth.
[12] From the perspective of evolutionary psychology the experiences and behaviors associated with love can be investigated in terms of how they have been shaped by human evolution.
[15] It has been suggested that the human capacity to experience love has been evolved as a signal to potential mates that the partner will be a good parent and be likely to help pass genes to future generations.
[16] Biologist Jeremy Griffith defines love as 'unconditional selflessness',[17] suggesting utterly cooperative instincts developed in modern humans' ancestor, Australopithecus.
Studies of bonobos (a great ape previously referred to as a pygmy chimpanzee) are frequently cited in support of a cooperative past in humans.
[20][21] The primary neurochemicals (neurotransmitters, sex hormones, and neuropeptides) that govern these drives are testosterone, estrogen, dopamine, oxytocin, and vasopressin.
[20][23] Sex drive is modulated primarily by activity in the mesolimbic dopamine pathway (ventral tegmental area and nucleus accumbens).
[20] Trace amines (e.g., phenethylamine and tyramine) play a critical role in regulating neuronal activity in the dopaminergic pathways of the central nervous system.
[31] Their work builds on previous studies of the importance of physical contact and affection in social and cognitive development, such as the experiments conducted by Harry Harlow on rhesus monkeys, which first established the biological consequences of isolation.
[32] In 2000, a study led by Semir Zeki and Andreas Bartels of University College London concluded that at least two areas of the brain become more active when in love.
The authors also found a correlation (r=0.496, p=0.002) between activation of a region of the angular gyrus with a passionate-love scale measuring subjective feelings of love.
[35] The common motivation whether it be love romantically or through a non-intimate companion can be connected to positive feelings and rewards that in turn, form social bonds.
