Want to stick to your resolutions? Then remember, the brain is your worst enemy

As the cloying fug of the festive period lazily begins to lift here on the Science lite desk, we take no pride in the fact that we have already made - and broken - more New Year resolutions that we care to write down.

Heads slightly drooped in shame (or is that still the hangovers?) we got to thinking - why is it so hard to decide something, and then stick to it? Just why is willpower so - well, powerless?

Could it be a question of evolutionary time-lag? Giving up things that are bad for us is, after all, a very modern problem. Indeed, even the concept of ‘things that are bad for us’ is - in evolutionary terms - at the very cutting edge of contemporary worries. No evidence has, as yet, come to light of Neanderthal mans’ attempt to form a smoking cessation support network. Or of ancient cave walls adorned with rudimentary rock art signs warning of the dangers of eating too much fatty mammoth meat.

A further clue to the weakness of resolutions is hinted at when we consider where willpower ‘lives’. Oddly enough the excesses of the festive period have in all likelihood delivered a kind of homing beacon to the doorstep of willpower. The brain area largely responsible for willpower, the prefrontal cortex, is located just behind the forehead - an area painfully highlighted, certainly for us, if you are sporting an alcohol induced post-festivity headache.

So what about its ‘location’ suggests limitations? Well, in short the prefrontal cortex is already pretty damn busy. Neuroscientists have discovered that this area is in charge of keeping us focused, handling short-term memory and solving abstract problems - asking this overworked sliver of cortex to take charge of turning down that extra bit of chocolate orange is often more than it can take.

Now if all this is beginning to sound like the rantings of someone desperate to justify their complete failure to keep any resolutions - then you are correct. But, as it happens, we have managed to cobble together some evidence for it.

One such piece of evidence - although admittedly it comes from the world of marketing, we leave you to draw your own conclusions on that - shows how the ‘busyness’ of the prefrontal cortex can affect willpower.  The experiment, led by Baba Shiv at Stanford University, involved several dozen undergraduates who were divided into two groups. One group was given a two-digit number to remember, while the second group was given a seven-digit number. Then they were told to walk down the hall, where they were presented with two different snack options: a slice of chocolate cake or a bowl of fruit salad. The students with seven digits to remember were nearly twice as likely to choose the cake as students given two digits.

Could it be that the working memory employed to remember the seven-digit number pushed any sense of willpower to the sidelines? A casualty of a higher cognition deemed more important by evolution?

And there is one more twist to the resolution tale. It would seem exerting willpower is a very energy intensive process. Professor Roy Baumeister, a psychologist at Florida State University found that students who fasted for three hours and then had to perform a variety of self-control tasks, such as focusing on a boring video or suppressing negative stereotypes, had significantly lower glucose levels than students who didn't have to exert self-control.

This would mean that often the things we are trying to give up at this time of year - chocolate, sugar, fizzy drinks - may well help the willpower on its way, ironically making it harder to refrain after we stop consuming them.

A cruel twist of nature then, this human compulsion to give things up - at once a burning priority and unimportant all-so ran for our minds. A mismatch of requirements for the conscious whole and the cognitive subdivision charged with the unwanted job of willpower guardian.

Now, will someone please pass me the paracetamol. And that last mince pie.