London (PTI): Humans prefer to be addressed in right ear and are likely to perform a task when the request is in the right ear rather than the left, say researchers.

Three studies by the University Gabriele d'Annunzio in Italy have revealed that a natural side bias, which depends on hemispheric asymmetry in the brain, actually manifests itself in everyday human behaviour.

According to the researchers, one of the best known asymmetries in humans is the right ear dominance for listening to verbal stimuli, which is believed to reflect the brain's left hemisphere superiority for processing verbal information.

"Our studies corroborate the idea of a common ancestry in humans and other species, of lateralised behaviour during social interactions, not only for species-specific vocal communication, but also for affective responses," said Luca Tommasi, who led the studies.

They have based their findings after specifically observing ear preference during social interactions in noisy night club environments on a group of people.

In the first study, 286 clubbers were observed while they were talking, with loud music in the background. In total 72 per cent of interactions occurred on the right side of the listener.

These results are consistent with the right ear preference found in both laboratory studies and questionnaires and they demonstrate the side bias is spontaneously displayed.

In the second study, the researchers approached 160 clubbers and mumbled an inaudible, meaningless utterance and waited for the subjects to turn their head and offer either their left of their right ear.

They then asked them for a cigarette. Overall, 58 per cent offered their right ear for listening and 42 per cent their left. Only women showed a consistent right-ear preference. In this study, there was no link between number of cigarettes obtained and the ear receiving the request.

In the third study, the researchers intentionally addressed 176 clubbers in either their right or their left ear when asking for a cigarette. They obtained significantly more cigarettes when they spoke to the clubbers' right ear compared with their left.

Taken together, these results confirm a right ear/left hemisphere advantage for verbal communication and distinctive specialisation of the two halves of the brain for approach and avoidance behaviour, the researchers said.

The findings are published in the latest edition of the 'Naturwissenschaften' journal.