Neurobiology of Generosity

First published in NAAP News (Summer 2012 issue):

by Inna Rozentsvit

“The true meaning of life, Wesley, is to plant trees under whose shade you do not expect to sit.” (Nelson Henderson)

“One day …Bob May gave me some advice: ‘You never lose for being too generous’. I was impressed because Bob is a winner.” (Martin A. Nowak)

We live in generous times. Millions of dollars are donated to various social causes and to unrelated people, who might never meet each other in their life time. Are we hard-wired for generosity or is it a learned behavior? Is it contagious? Can we imagine it being pathological? It seems that our answers will differ depending on what we are, professionally and culturally (given that inter-personal and gender-based variations are taken out of equation). Overall, generosity is perceived as giving to others at costs to oneself.  As social philosopher Adam Smith stated in his greatest book, The Theory of Moral Sentiments (1790): “How SELFISH soever man may be supposed, there are evidently some principles in his nature, which interest him in the fortune of others, and render their happiness necessary to him, though he derives nothing from it except the pleasure of seeing it.” Can this pleasure be pathological?

First, it is important to really distinguish generosity from altruism. Generosity involves more of the ability of sharing with another person some material and non-material possessions, and it is a social phenomenon; while in altruism, selflessness and putting the interests of others above one’s own interests are the most prominent characteristics, and denial of one’s own needs (which can be considered pathological in certain circumstances) is more feasible there. The earliest reference to pathological generosity (PG) in psychoanalytic literature can be found in Hilda Lewinsky’s 1951 article “Pathological Generosity.” As per Lewinsky, giving in PG originates from “oral and anal fixations,” as a reaction to “greed for love,” which cannot be satisfied through sadism, and as an “illusion of ultimate reciprocity.” She compares PG with unconscious technique of “homoeopathic magic.”

My search for neurobiological correlates of generosity and PG brought to light the following.

Studies of neuroeconomists Zak, Stanton, and Ahmadi (2007) and neuropsychiatrists Bora, Yucel, and Allen (2009) concluded that humans are “routinely” generous (while being generous means in their terms as “offering more than the other expects”), and that generosity is routed in empathy (by the principle ‘what fire together – wire together!’), and that it is an expression of their “human affiliative behavior.” They also suggested that neuropeptide/ neurohormone oxytocin (OT) is intimately connected to generosity, since OT significantly increased generosity in the subjects of their research. Those who had an infusion of OT were 80% more generous in splitting money with a stranger, in comparison with those injected with placebo. It is interesting to note that in the same study, OT did not have such an effect on unilateral (altruistic) money transfer. Although this type of studies did not gain “final” conclusion about all the factors involved in generosity, all interpersonal variations included “emotional identification with another person” (or empathy), altruism, and influence of OT (with OT being a twice stronger factor than altruism).

Another group of neuroscientists (Moll, Krueger, Zahn, Pardini, Oliveira-Souza, and Grafman, 2006) used functional MRI (fMRI) technology to investigate charitable behavior, which included anonymous material sacrifice while endorsing or opposing societal causes based on moral beliefs.  In this study, fMRIs showed that “the mesolimbic reward system is engaged by donations in the same way as when monetary rewards are obtained.” This study also showed that the areas of more primitive mechanisms of social attachment and aversion (located in orbito-frontal areas) are involved in decisions of supporting or opposing societal causes, while the anterior portions of prefrontal cortex are involved in altruistic choices. As the editors of the Science Daily put it,“…‘joy of giving’ has an anatomical basis in the brain – surprisingly, one that is shared with selfish longings and rewards.”

Some of the recent studies do describe different sorts of PG, mostly related to impulsive-compulsive phenomena of “excessive and inappropriate philanthropy” in patients treated with dopaminergics for Parkinson’s disease, as in the study by O’Sullivan, Evans, Quinn, Lawrence, and Lees (2010), described in their article “Reckless Generosity”. Similar dopaminergic mechanisms of pathological (or “reckless”) generosity should be suspected in patients with various manic conditions, with out-of-control impulsive behaviors.

Overall, neuroimaging and other neuroscientific experiments in the roots of voluntary giving (generosity) and PG are still to find the golden recipe of this phenomenon, but today, we know for sure that it involves neurobiological pathways which process empathy, emotions, and social information, as well as primitive (or evolutionary early) mesolimbic (mid-brain) dopamine-based reward system; and oxytocin, the hormone of trust, perspective taking, mothering, and bonding. We also know from the same studies that generosity makes people happier. Maybe in return, the pursuit of happiness makes us more generous, as these two processes regulate each other..? This is still to be investigated.