MOST of us, at one time or another, have blamed our mistakes on "being in a bad mood". Now it appears that happiness, just as much as an attack of the blues, can throw our performance out of kilter. Psychologists at the University of Wales, Bangor, have found that being in a good mood may have a similar effect on some aspects of our thinking as a frontal lobotomy.
The team, led by Dr Mike Oaksford (now based at the University of Warwick), looked at the ways in which our mood can affect the quality of our analytical thinking. Dr Oaksford, a specialist in the field of human reasoning, has recently been awarded the Spearman Medal by the British Psychological Society for his non-mood-related work. He became interested in mood states after hearing about research carried out by the American psychologist Alice Isen at the University of Maryland. "She did a very interesting study on how positive mood, being happy, affects creative thinking, using a lovely task called Duncker's Candle Problem."
In this, the subject is given a small box of tacks, a box of matches and a candle, and told to attach the candle to the wall and light it in such a way that the wax doesn't drip on the floor. The solution is to empty the tack box, fasten it to the wall, and use it as a candle-holder. It is an exercise in lateral thinking, requiring a leap of insight rather than a series of logical steps. Isen found that subjects who were in a positive, happy mood were much better at solving the problem than people in either an emotionally negative or neutral state.
Prompted by Isen's findings, Oaksford and his colleagues set out to find what sort of effect mood states have on analytical thinking. Waiting to see what side of the bed volunteers had got out of was hardly a reliable method, so some means of putting them in the right mood was needed.
"Psychologists have induced mood states in a variety of ways," says Oaksford. "Hypnosis is one method, music another - usually short pieces that have been tested by musicologists for their elevating or depressing effect. Then there's something called 'Belton's Self Statements', where essentially someone sits there and says nice things about themselves for a while. Or they say negative things."
The method Oaksford chose, however, was the same as Isen's; he used short film clips that had previously been tested to ensure they had the desired mood-inducing effect. Clips from It'll Be Allright On The Night were used to induce a happy mood, while a clip from a documentary on stress brought about a more negative mood state. Two "neutral" mood control groups were also set up: one was shown an emotionally neutral film clip (from a David Attenborough natural history documentary), the other no film at all. "It was crucial that we had two control groups, because we wanted to make sure it wasn't just seeing a film that was having these effects," says Dr Oaksford.
Once they were feeling suitably good, bad or indifferent, the 62 subjects (mainly psychology undergraduates) were told to imagine they were immigration officials at an airport. The aim was to present them with a reasoning task as close as possible to something they might encounter in their day-to-day lives, in this case the enforcement of a regulation preventing anyone from entering the country without a cholera innoculation.
Using a variation of something called "Wason's Selection Test", they were shown four immigration forms from four different passengers. The catch was that they were shown only one side of each form, either the side that indicated whether the passenger intended to enter the country or was just in transit, or the side that contained a list of the passenger's innoculations. The task was to decide which of the four forms they needed to examine further, to ensure that the regulation wasn't being breached.
The correct response was to …