Uncontrolled morning urges

The trouble with setting an alarm is that what seems sensible at midnight will seem absurd at 7am. At midnight, you are swayed by the long-term rewards -job, responsibilities, family - while in the grimness of winter dawn, it is the short-term benefits of the warm bed and its drowsy cocoon that dominate your consciousness. That you manage to struggle from under the duvet out into the punishment that is a winter Monday may be one of the supreme achievements of evolution. Psychologists call this achievement self-control.

Self-control is what a lot of us believe we do not have in some aspect of our lives. Who among us does not wish that we could eat less fat, or smoke fewer cigarettes, or drink less alcohol, or work fewer hours, or take more exercise, or be less bad-tempered, or be more assertive, or not bite our nails, or spend less money, or have less casual sex... and so on? Self-control is what we invoke to explain how people manage to assuage the thirst for short-term gratification in favour of longer-term rewards. And it is the impoverishment of self-control that is often invoked to explain those pathologies such as alcoholism and drug addiction.

Cognitive neuroscience would be seen by many as the theoretical framework of choice these days to offer the definitive account of self-control, preferably backed up with a few Pet-scan studies showing the brain areas activated when a short-term temptation is succumbed to compared with when it is successfully resisted. As a cognitive neuroscientist, deeply enamoured of these lovely but pricey machines, I would even hazard a guess that the orbito-frontal or medial-frontal lobes should be a candidate for slamming on these motivational brakes in the brain. The self-control centre in the brain; located, sorted out, explained. QED.

But then this guy, Howard Rachlin, from New York, who has studied pigeons pecking at lights for the past 30 years, comes along with this spare, readable and utterly scholarly little book on the science of self-control. Let's get one thing straight, he says: context is everything. He is a teleological behaviourist, who says that behaviour can be understood, predicted - and hence controlled - only in its temporal and environmental context. You want to know whether someone is going to succumb to temptation and take his scoop? Forget your fancy brain scanner: tell me what he did the past 20 times he faced this choice; tell me what his discriminative stimuli are for this behaviour.

And when you study what people (and pigeons) do when faced with repeated sequences of these short-term/long-term choices, you find patterns that can be described by simple mathematical equations. The fitted parameters of these find, reassuringly, that pigeons are about a million times more short-termist and impulsive than we are; that being said, the equations fit pecking for grain and gambling for money in a most non-species-ist way.

Behaviourism lost favour in the cognitive revolution, but cognitive neuroscience will have to rediscover the work of Rachlin and his colleagues if it is to have a chance of addressing some of the big questions about human behaviour. Like, why I shall probably make it out of bed at 7am tomorrow morning.

Ian Robertson is professor of psychology, Trinity College, Dublin, Ireland.