Monetary sacrifice among strangers is mediated by endogenous oxytocin release after physical contact By V. Morhenn, J. Park, E. Piper & P.J. Zak
Why Study Virtues?Virtuous behavior (by oneself and others) is associated with greater happiness (Haidt, 2006; Peterson & Seligman, 2004)Robust evolutionary models for virtuous behavior do not exist (e.g. when an interaction is blinded)Arguably, virtues are the social glue of relationships and societies The neural substrates of virtues are not well understood
QuestionsWhy sacrifice to help a stranger when no one is looking?Why sacrifice to a stranger when it is costly?Why do we have the typical human ritual of pressing palms together (or sometimes bodies)?Could these be related?
SacrificeFrom Middle English meaning "to make sacred
Sometimes when you sacrifice something precious, you're not really losing it. You're just passing it on to someone else.
In rodents, and in some human studies, stroking releases OT
Q: Is there any effect of endogenously released OT on social behaviors?
RationaleHYPOTHESES: 1. Massage will increase OT 2. DOT will predict the degree of monetary sacrifice to a stranger
OxytocinOur lab has previously shown that
oxytocin is released by the brain when we are trusted by a stranger and is associated with trustworthiness
Oxytocin infusion can cause one to be more trusting toward a stranger
Oxytocin infusion can increase generosity towards a stranger substantially
Subjects randomized to receive either
A) a 15min moderate pressure back massage by a licensed massage therapist, clothes on in a semi-private room, or
B) rest quietly for 15mins in the same room.
Subjects then play the trust game 1 time.Blood draw before massage and after decisions.
A control group got a massage and blood draw but didnt play the trust game.
Subjects receive $10 when they show up and are randomly and anonymously matched in pairsTrust signalTrustworthinessThe Trust GameBlood draws
Sacrifice: A DM2 transfer in trust game that is greater than the average return trustworthiness (or more strongly, unrelated to the amount received)
Nash Equil. predicts NO SACRIFICE
- FindingsGroups MT: massage+trust [MT], N=42; RT: rest+ trust N=30; M: Massage only N=2453% femaleOT changeM no change (basal OT=187.3 pg/ml, activated OT=189.5 picogram/mililiter, p=.62)MT higher (basal OT=192.4 activated OT 221.5, p
FindingsOT & Behavior DM1: DOT not related to trust DM2: DOT corr with signal of trust recd in MT (p=.03); weakly in RT (p=.10) DOT predicts monetary sacrifice in MT and RT groups controlling for $ recd (p=.04) OLS predicts that massage induces an extra $4.94 sacrifice (actual=$4.85) RT: $ recd & DOT predict $ returned by DM2s; MT: only DOT matters (!)
Implications: SacrificeNo gender diff in sacrifice (p=.32)Butwomen were more susceptible to the massage prime (female basal OT 235.6 pg/ml, male basal OT =179.5 pg/ml, p=.05)
MT: higher basal OT => larger DOT (p=.05)women drive our results!Entire sample, Corr ( basal OT, DOT)= -.28, p=.007)
ImplicationsFemale sacrifice to offspring is the hallmark of mammals, and OT appears to explain sacrifice to a stranger, esp. in women. Touch appears to prime the release of OTWhy? OT causes ventromedial dopamine release. It may feel good to sacrifice (otherwise, why do it?)
Current ResearchTrust, Oxytocin and fMRI
Side NotesTrust and Oxytocin-Massaging Politicians could improve the country?
-U turns signs
-Dr. Muhammad Yunus and the Grameen Bank
-Former English Subjects
"No society can surely be flourishing and happy, of which by far the greater part of numbers are poor and miserable," Adam Smith (1776).
Chinese proverb. Nowadays, we try to find out why we are normal rather than abnormal which area has been researched so much.Go and shake handPlease develop these tasks as you see them fit.Please develop these tasks as you see them fit.Please develop these tasks as you see them fit.Please develop these tasks as you see them fit.Utility maximization predicts that Nash equilibrium to be no trust and no sacrifice. Nash eq. is the best course of action given an action. Please develop these tasks as you see them fit.Please develop these tasks as you see them fit.Please develop these tasks as you see them fit.Please develop these tasks as you see them fit.Please develop these tasks as you see them fit.The OT receptors are limited and can cause a ceiling effect on OT binding.This finding suggests a latent mechanism for motherhood. We speculate that dendrites in the dopamine system might accumulate during touch, and when the signal of trust comes, it could cause it to burst, and it may feel good.*Human vs. Computer results for DM1. Uncertainty is present in this role. Use the dice.*$27 for 42 women to buy bamboo and manufacture furniture