Ivory Towers: Is smiling a pain in the neck?

KEEP smiling, Tony Blair, and show your teeth, but don't tilt your head if you want people to think you're happy. A recent study, 'The Effect of Smiling and of Head Tilting on Person Perception' (by Otta, Lira, Delevati, Cesar and Pires, The Journal of Psychology, vol 128, 1994, 323- 331), confirms that expression and posture may alter the judgements made about a person, and that the broad, toothy grin is generally taken as a strong sign of leadership, optimism and reliability.

Their experiments involved showing 322 Brazilian undergraduates slides of a man or woman, with head tilted or upright, smiling or non-smiling. The smiles themselves could be closed (with teeth covered), upper (top lip raised, lower teeth covered) or broad (upper and lower teeth exposed). Earlier research had shown that the upper smile is the most common form, particularly in a social context. The closed smile is associated more with solitary enjoyment, while the broad smile correlates with laughter.

The two 'stimulus persons' were a man aged 30 and a woman aged 28, and eight photographic slides were taken of each: three different smiles and a non-smile, with head tilted or upright. Subjects were then shown individual slides and asked to rate the person in the picture on each of 12 criteria: optimism, conciliation, calmness, reliability, leadership, happiness, intelligence, attractiveness, beauty, sympathy, sincerity and kindness.

The results showed that smiling faces generally attracted considerably more positive scores than non-smiling ones, and on 11 of the 12 factors - particularly reliability, happiness, leadership and optimism - the broad smile did best of all. (Only adopt a closed smile if you want to look conciliatory).

By contrast, head posture only seemed to affect results if sex was taken into account. Female subjects judged the male more handsome if his head was tilted, although they thought the female more beautiful and more reliable when her head was upright. Upright heads, especially female ones, are perceived as happier than tilted heads.

The researchers suggest that the sex differences may reflect head-tilting as an appeasement gesture used in courtship display. The tilt- headed female is suspected by other females of faking it.