Right ear is ‘better for hearing’

The left-side of the brain processes much of what is heard in the right ear

If you want to get someone to do something, ask them in their right ear, say scientists.

Italian researchers found people were better at processing information when requests were made on that side in three separate tests.

They believe this is because the left side of the brain, which is known to be better at processing requests, deals with information from the right ear.

The findings are reported online in the journal Naturwissenschaffen.

We can also see this tendency when people use the phone, most will naturally hold it to their right ear Professor Sophie Scott, of University College London

In the first study, 286 clubbers were observed while they were talking with loud music in the background.

In total, 72% of interactions occurred on the right side of the listener.

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

They then asked them for a cigarette.

Overall, 58% offered their right ear for listening and 42% their left.

In the third study, the researchers intentionally addressed 176 clubbers in either their right or their left ear when asking for a cigarette.

The researchers obtained significantly more cigarettes when they spoke to the clubbers’ right ear compared with their left.

Brain

In conclusion, the researchers said: “Talk into the right ear you send your words into a slightly more amenable part of the brain.

“These results seem to be consistent with the hypothesised specialisation of right and left hemispheres.”

Professor Sophie Scott, of the Institute of Cognitive Neuroscience at University College London, agreed.

“Most people process speech and language on the left-hand side of the brain and while it is not cut-and-dry a lot of what goes in our right ear will be dealt with by the left-side of the brain.

“The other side of the brain is more involved in things such as interpreting emotion and that is why we have these kind of findings.

“We can also see this tendency when people use the phone, most will naturally hold it to their right ear.”

Taxi drivers ‘have brain sat-nav’

The knowledge: London cabbies are famous for knowing their way around

Scientists have uncovered evidence for an inbuilt “sat-nav” system in the brains of London taxi drivers.

They used magnetic scanners to explore the brain activity of taxi drivers as they navigated their way through a virtual simulation of London’s streets.

Different brain regions were activated as they considered route options, spotted familiar landmarks or thought about their customers.

The research was presented at this week’s BA Science Festival.

Earlier studies had shown that taxi drivers have a larger hippocampus – a region of the brain that plays an important role in navigation.

Their brains even “grow on the job” as they build up detailed information needed to find their way around London’s labyrinth of streets – information famously referred to as “The Knowledge”.

“We were keen to go beyond brain structure – and see what activity is going on inside the brains of taxi drivers while they are doing their job,” said Dr Hugo Spiers from University College London.

The scientists used functional magnetic resonance imaging (fMRI) to obtain “minute by minute” brain images from 20 taxi drivers as they delivered customers to destinations on “virtual jobs”.

The scientists adapted the Playstation2 game “Getaway” to bring the streets of London into the scanner.

After the scan – and without prior warning – the drivers watched a replay of their performance and reported what they had been thinking at each stage.

“We tried to peel out the common thoughts that taxi drivers tend to have as they drive through the city, and then tie them down to a particular time and place,” said Dr Spiers.

The series of scans revealed a complex choreography of brain activity as the taxi drivers responded to different scenarios.

The hippocampus was only active when the taxi drivers initially planned their route, or if they had to completely change their destination during the course of the journey.

The scientists saw activity in a different brain region when the drivers came across an unexpected situation – for example, a blocked-off junction.

Another part of the brain helped taxi drivers to track how close they were to the endpoint of their journey; like a metal detector, its activity increased when they were closer to their goal.

Changes also occurred in brain regions that are important in social behaviour.

Taxi driving is not just about navigation: “Drivers do obsess occasionally about what their customers are thinking,” said Dr Spiers.

Animals use a number of different mechanisms to navigate – the Sun’s polarized light rays, the Earth’s magnetic fields and the position of the stars.

This research provides new information about the specific roles of areas within the brains of expert human navigators.

Vitamin linked to brain shrinking

Many people are deficient in vitamin B12

A vitamin found in meat, fish and milk may help stave off memory loss in old age, a study has suggested.

Older people with lower than average vitamin B12 levels were more than six times more likely to experience brain shrinkage, researchers concluded.

The University of Oxford study, published in the journal Neurology, tested the 107 apparently healthy volunteers over a five-year period.

Some studies suggest two out of five people are deficient in the vitamin.

The rate of shrinkage of the brain as we age may be partly influenced by what we eat Professor David Smith Oxford University

The problem is even more common among the elderly, and recent moves to supplement bread with folic acid caused concern that this could mask B12 deficiency symptoms in older people.

The Oxford study looked at a group of people between 61 and 87, splitting it into thirds depending on the participants’ vitamin B12 levels.

Even the third with the lowest levels were still above a threshold used by some scientists to define vitamin B12 deficiency.

However, they were still much more likely to show signs of brain shrinkage over the five-year period.

Liver and shellfish

Professor David Smith, who directs the Oxford Project to Investigate Memory and Ageing, said he now planned a trial of B vitamins in the elderly to see if taking them could slow brain shrinkage.

He said: “This study adds another dimension to our understanding of the effects of B vitamins on the brain – the rate of shrinkage of the brain as we age may be partly influenced by what we eat.”

Shrinkage has been strongly linked with a higher risk of developing dementia at a later stage and Rebecca Wood, the chief executive of the Alzheimer’s Research Trust, said further research was needed.

“This study suggests that consuming more vitamin B12 through eating meat, fish, fortified cereals or milk as part of a balanced diet might help protect the brain. Liver and shellfish are particularly rich sources of B12.

“Vitamin B12 deficiency is a common problem among elderly people in the UK and has been linked to declining memory and dementia.”

Dr Susanne Sorensen, from the Alzheimer’s Society said: “Shrinkage is usually associated with the development of dementia.

“As vitamin B may be given as a food supplement, it may be useful to include tests of vitamin B levels in the general assessment of health of older individuals.

“This is another example of why it is crucial for people to lead a healthy lifestyle with a balanced diet rich in B vitamins and antioxidants.

“The best way to reduce your risk of developing dementia is to keep active, eat a balanced diet, don’t smoke and visit your GP to get your blood pressure and cholesterol checked.”