Delay discounting – a problem with will
Unlike other animals, we have the ability to project into the future – to consider where we are heading and what we may be doing in the future. We are strongly motivated by future possibilities. We can endure sacrifices NOW to go on holiday LATER. We can even imagine our lives in decades hence and plan for it – when we put aside money for our pension. It’s quite extraordinary how we can live in, and plan around, the future as well as the present.
But if we were perfectly rational, we’d weight the rewards that we will get in the future as strongly as the rewards we will get right now – whether it’s a tub of icecream or a new car. But psychologists have shown that we are subject to a bias known as delay discounting – our tendency to discount (undervalue) the value of a future reward as a function of its temporal distance. In other words, rewards that are further away are not weighted as much as rewards that are close.
Thinking of rewards in the future vs thinking of rewards here and now activate different brain networks, as shown in a brain imaging study by Samuel McClure and his colleagues. They had people decide between getting an Amazon gift certificate right away, or a slightly larger gift certificate in 2-4 weeks time. They thought about these options while lying in an fMRI brain scanner that took images of their neural activity. To quote from Frontal Cortex, these are the results they obtained:
When subjects contemplated gift certificates in the distant future, brain areas associated with rational planning, like the medial prefrontal cortex, were more active. These cortical regions urge us to be patient, to wait a few extra weeks for the bigger gain.
On the other hand, when subjects started thinking about getting a gift certificate right away, brain areas associated with emotion – like the midbrain dopamine system and nucleus accumbens – were turned on. These are the cells that tell us to take out a mortgage we can’t afford, or run up credit card debt when we should be saving for retirement. All they want is a reward, and they want it now.
By increasing or decreasing the amount of money on offer in each option, McClure found a kind of neural ‘tug of war’ unfold, in which the final decision – to wait for future goodies or to indulge in goodies right in front of you – was largely the result of which brain region showed more activation. Those people who were able to wait for the larger gift certificate in the future showed more activity in the prefrontal cortex, allowing them to choose the more rational option by overcoming the ‘delay discounting’ bias towards immediate gratification. Those with more ‘delay discounting’ bias had more dopamine system (midbrain) activation. The ability to delay instant gratification, overcoming the impulsivity of the ‘now’, is an important part of what psychologists call ‘executive control’. Executive control is known to be important for overall success in life in social and financial terms, allowing for prudent investments and long-term planning.
Imagine what you will be doing in the future
A study this month by neuroscientists at the University Medical Center Hamburg-Eppendorf have extended this research. These neuroscientists have found a useful application for our own decision making, helping us make decisions with a more self control rational long term perspective.
In their experiment, participants were given a variety of different rewards from 20 to 35 euros, and a variety of reward delivery times (immediately, 30 days, or 45 days). This was the usual ‘delay discounting’ set up, in which they could demonstrate that the more distant the reward, the less it was valued, and the less it factored into the decision making process. But the researchers added an interesting, and revealing, twist: in half of the decision trials, the participants were prompted to think about what they would be doing in their lives at the same time as the reward would be given (in 30 or 45 days time). The results were very interesting: when people were cued to think about personal future events, they were significantly LESS likely to undervalue the future reward (delay discounting) – and their self-control increased the more vividly they could imagine their future lives.
This study was also done in an fMRI brain imaging magnet. When people imagined future events, the prefrontal cortex cortex was activated, but also distinct brain areas related to our self identity – our ‘autobiographical self’.
Practical tip for better decision making
This insight provides us with another tool in our cognitive kit for delaying gratification, which has widespread benefits. Before you decide to make a big purchase, or take out a mortgage, or whatever, spend a minute or two thinking about what you’ll be doing with your life in the future. What you imagine doesn’t have to have any connection to the decision in question – it’s enough to simply contemplate your future.
