Happiness is a difficult concept to define and measure. One foundation on which concept of happiness is built is rewards. Momentary measures of happiness ( =hedonic well-being) can be studied by sampling the experiences of individuals and analysing how these are related to antecedent life events /rewards. However, we do not know much about how the cumulative influence of such daily life events are aggregated into subjective feelings.
Is it the outcome of tasks ( reward) or the expectation that determine happiness?
What are the brain correlates of such momentary happiness?
Can the happiness be predicted using computational models / formula?
Robb B. Rutledgea, Nikolina Skandalia, Peter Dayanc, and Raymond J. Dolan from University College London reports the results of an interesting study that attempts to answer these questions?
Participants performed a probabilistic reward task (gambling) and were asked about their level of happiness after every few trials. ( i.e. overall emotions state ). Participants were scanned (fmRI) while they made choices. The team created a computational model of momentary well-being that includes expected values of chosen gambles and the difference between experienced and predicted rewards ( both from dopamine activity) and looked at its ability to predict momentary happiness. Additional behavioural experiments were carried out to validate these models. 18420 people participated in a smart phone experiment ( The great brain experiment/ app) which essentially repeated the lab experiment in a large cohort.
Momentary happiness reflects NOT how well things are going, BUT instead whether things are going BETTER than Expected. This includes positive and negative expectations, even in the absence of outcomes.
Rewards received many trials ago have no influence on current happiness in the task. Recent rewards affected ongoing reactive happiness rating.
Overall effect of expectations on happiness is negative. i.e. positive expectations effectively reduce the overall emotional impact of trials with positive outcomes.Negative expectations, reduce the overall emotional impact of trials with negative outcomes. ( = if expecting negative outcome, then prepare with more negative expectations to reduce distress later)
Lowering expectations can increase the probability of positive outcome . ( used in sports= ‘underdog’ approach).However lowering expectations reduce well-being before an outcome arrives.
A sufficiently negative expectation can help create an overall positive emotional impact from a negative event. ( =predict a longer delay ( flight/ parcels/appointments) and anything less than that reduce the distress.
Remembered feelings depend most on how experiences were at the END. (= painful medical procedures are remembered as less unpleasant when they end with a less painful period).
Phasic dopamine release in striatum is linked to momentary happiness.
Momentary happiness is a result of the combined influence of recent reward expectations and prediction errors arising from those expectations.
Comments: It is not what actually happens that determine how you feel, it is what happened in relation to your expectation that matters.
Summary of the article:
Rutledge RB, Skandali N, Dayan P, Dolan RJ. Proc Natl Acad Sci U S A. 2014 Aug 4