If you're thinking of asking your beloved to marry you, make sure that you utter your declaration of love into his or her left ear; it may increase your chances of hearing a heart-lifting “yes”. New research suggests that declarations of love, jokes, or words of anger are best remembered when they are heard through the left ear, while instructions, directions and non-emotional messages have more impact on the right side.

It is all to do with how our brains process information. Although the left and right hemispheres, or sides, of the brain are similar structures, they have specialised functions. The left side, it is suggested, is more logic-based and dominant, while the right is the more imaginative side, more visual, intuitive, emotional and spatially aware. Because the right side of the brain controls the left side of the body, the left ear has been shown in some research to be the route to the emotional side of the brain, and the right ear to the non-emotional, logical side.

But it's not just ears that are affected. The right eye has been shown to be best for processing colours, the right foot is the most vulnerable to tickling, the left cheek the more favourable one to kiss, and the left side is the favoured one for holding babies. Support for the idea comes from a number of psychological and brain scanning studies, and from research based on patients with brain injuries or structural changes.

The different hemispheric roles are, for example, more pronounced in patients who have no corpus callosum, the structure that connects the two hemispheres. And studies of stroke patients have shown that those who suffer left-side damage tend to have more problems with speech and language than those who have right-side damage. Here is a round-up of the latest research that delves into the mysteries of how the two halves of our brains work.

TELLING JOKES

You've got to laugh, especially if the joke comes through the left ear. Ongoing research at the University of California shows that the right hemisphere seems to be more involved in the processing of punch lines when volunteers were exposed to jokes. The researchers say: “Results suggest that joke-relevant information was more active in the right hemisphere.”

CRADLING BABIES

Research suggests that 70 to 85 per cent of women cradle babies on the left, irrespective of handedness. According to research at Sussex University, they do so because it helps them to better understand their child's emotional and physical needs. According to the researchers, the left position directs important infant responses to the right side of the mother's brain, the hemisphere used for emotional response. “Left-sided cradling provides an advantage in the bonding process by giving the mother fast intuitive access to the baby's requirements,'' they say.

WHISPERING SWEET NOTHINGS

Loving words - and angry ones - are likely to have the biggest impact through the left ear. The research at Sam Houston University of America, based on 1,120 people, showed that the subjects were able to recall more emotional words connected with love and anger when they were delivered though the left ear. When emotional words were presented in the left ear, the percentage of recall accuracy was 69 per cent compared with 56 per cent for the right ear.

A NOSE FOR SMELLS

Aftershave and flowers may have the biggest effect on a woman's left nostril. In research at the University of Pennsylvania Smell and Taste Centre, different smells were presented to the left and right sides of the nose of 60 left or right-handed people. Results show that the biggest impact, seen only in women, was when the smells were presented to the left, possibly because of its link to the more emotion-sensitive side of the brain.

FANCY A LITTLE TICKLE?

With the help of special tickling apparatus, researchers tickled the left and right feet of volunteers to assess reactions. The volunteers rated the strength of the tickle sensation and results show that the right foot was significantly more sensitive than the left, irrespective of both hand and foot preference.

FINDING RELIGION

When researchers in the United States played religious or spiritual words into the left ears of volunteers, they found that recall accuracy was 66 per cent, compared with 54 per cent for the right ear. The reverse was found for non-religious words. Researchers say that when religious words are heard in the left ear, the signals travelled to the right hemisphere, which is more receptive to non-logical thought. “One explanation is that it is the right hemisphere that performs functions normally not associated with logic and reason,'' says Dr Teow-Chong Sim, who led the study.

HOT SALES PITCHES

The left ear may be best for salesmen. In research at University College London, three sales teams used one of three headsets - left, right, both ears - for a day's selling of insurance by telephone. Sales were markedly influenced by the choice of headset. “People who chose to wear the left earpiece significantly outsold the others wearing right and stereo headsets. When sales are analysed in terms of individual differences in personal preference for type of headset, those who chose the left ear had an advantage.''

Exactly why is not clear, but one theory is that sale staff who opt to use their right ear may be more likely to use logic for selling, while those who use the left may have a more intuitive and responsive relationship with clients

PICTURE APPRECIATION

If you want to increase your appreciation of fine art, wink at the pictures. Studies indicate that the right hemisphere, and the left eye, best remembers pictures. Researchers at the University of Tromsø, Norway, showed a set of 1,500 pictures of animals, human faces, artefacts, landscapes and art paintings to the central vision of volunteers, and then to each eye separately. Memory for the images was then tested up to six days later. Results show that images that had been presented to the right hemisphere were better recognised than those shown to the left.

ANYONE FOR ATHLETICS?

Sprinters are best kicking off with their right foot. Research at the University of Calgary shows that those who start with their right foot at the rear had an overall 70 millisecond advantage over those with a left foot at the rear. The researchers say the results are consistent with the theory that the left hemisphere, which controls the right foot, is more involved in the control of movement. “The right-foot-rear response-time advantage found in the present study suggests that teachers and coaches in these events should emphasise a right-foot-rear stance for their athletes,'' say the researchers.

FACE RECOGNITION

The right hemisphere is better than the left at processing faces, but not if they are blurred. In research reported in the journal Perception, famous and non-famous faces were presented to the left and right visual fields. Half were blurred and half unblurred.

Blurred famous faces were responded to significantly faster when presented to the left visual field than when presented to the right visual field.

TEST A FRIEND

Watch the direction of a friend's gaze when you ask him or her these questions

1. Name a county that borders Cornwall.

2. Name three synonyms for “walking”.

3. What direction does the Queen face on a two pence piece?

4. Name three synonyms for “intelligence”.

Most people will look to the right when thinking about language-related questions (the even- numbered questions) and look to the left when thinking about the spatial questions (the odd- numbered questions). These eye movements are thought to be a consequence of the two sides of our brains processing different information.

Developed by Concordia College, Minnesota

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