Have you ever found that, whenever you try to achieve something, you often end up doing exactly the opposite? Like going to bed early to get a good night’s sleep, only to spend half of it awake waiting for the alarm clock to go off? Or attempting to relax and ending up feeling more stressed about your inability to let go?

My fear is blurting out the very thing that is supposed to remain unspoken. I say that as someone who a) talks quite a lot, and b) can have ungenerous thoughts and opinions. I recall going on a live radio programme during which I was supposed to say clever, insightful things to the insomniacs who rang in. Unfortunately, Pope John Paul II was on his deathbed that night. Being a non-believer, I really had nothing constructive to say about this state of affairs other than to note it with faux sadness. But a phrase containing a papal reference kept intruding into my fatigued consciousness. I cannot possibly type it; it is a vulgar rhetorical device that involves His Holiness, bowel evacuation and a forest, but I was overwhelmed by the fear that it would escape from my lips. Consequently, I uttered little of interest to anybody.

The Harvard psychologist Daniel Wegner has studied how we control our minds, and thinks he knows why at times we end up saying or doing exactly what we are trying so hard not to say or do. When we try to suppress an unwanted thought, eg, sex, our mind gets to work in two ways. Its first response is to make a real effort to steer clear of the heinous thought. But that automatically requires a second mental activity: the continuous monitoring of the thought to be avoided. If you are told to not think of a white bear, you have to stay mindful of the very thought you are not supposed to be thinking about. And when you’re tired or distracted, that mindfulness weakens. Suddenly the white bear has slipped the shackles of mental avoidance and ambled over the horizon, clear as day. In fact, this problem was referred to more than a century ago by Dostoevsky, who, in Winter Notes on Summer Impressions, challenged the reader: “Try to pose for yourself this task: not to think of a polar bear and you will see that the cursed thing will come to mind every minute.”

Wegner calls our mind’s ability to backfire an “ironic process”. His most recent paper, published yesterday in Science, boasts the delightful title: “How to Think, Say or Do Precisely the Worst Thing for Any Occasion.” His research, however, points to an implication that is more profound than simply blurting out the unsayable on radio.

He notes that people who try hard to be happy usually end up being sad, and those who try to be calm are generally anxious. When we demand too much of our brains, he suggests, they rebel against us. The ultimate sign of mental rebellion is illness, and Wegner believes that ironic processes might play a role in mental ill health. In his words: “. . . the more subtle and important possibility, as yet untested in large-scale studies, is that the attempt to control unwanted mental states plays a role in perpetuating them”.

One common feature of mental illness is that sufferers keep their symptoms to themselves. This, Wegner suggests, is an extreme and demanding kind of mental control that becomes all-consuming. Suppression becomes obsession. Wegner points out that studies that encourage the patients to abandon this suppression — by talking openly, or even writing down one’s deepest thoughts and feelings — has been shown to improve physical and psychological wellbeing.

For the healthy, Wegner’s message is: don’t try so hard. If you don’t make an extreme mental effort not to think of the white bear, or sex, or the Pope, then you are less likely to say or do the thing you are trying to avoid. I must remember that the next time I’m on Midnight Mumbles with that arse of a presenter, trying desperately not to patronise the friendless fruitcakes who ring in under the delusion that we’re actually interested in what they have to say. Oops.

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