Zapping brains of elderly can give them memory of a 20-year-old

PASSINg electric shocks through the brains of older people can give them the working memory of someone a third of their age, scientists have said.

It takes only a weak electrical current to temporarily reverse the memory decline of people over 60, the study found, as the pulses are thought to synchronise brainwaves making the brain more efficient.

Researchers asked 42 people aged 60 to 76 to complete a memory test where they had to spot the differences in very similar pictures shown three seconds apart. Compared to 42 people aged 20 to 29, the older group performed worse in the activity. But when they were zapped with electricity for 25 minutes their scores improved from around eight out of ten to nine out of ten.

This put them at the same level as people in their twenties.

Dr Robert Reinhart, who led a study on the technique at Boston University, said: ‘ These findings are important because they not only give us new insights into the brain basis for age-related working memory decline, but they also show us that the negative agerelated changes are not unchangeable – that we can bring back the more superior working memory function that we had when we were much younger.

‘This is important because everyone knows the global population is rapidly ageing.’ Scientists now believe older people can partly blame their bad memories on two regions of the brain getting ‘disconnected’. In young people, the temporal and prefrontal parts of the brain work together, providing short-term ‘working memory’ that makes it easy to remember shopping lists and phone numbers and to make decisions.

Their brainwaves – the electrical waves which ripple through the brain as cells work at the same time and ‘talk’ to each other – are all synchronised. In older people, these brainwaves were found to be out of rhythm.

The study, published in the journal Nature Neuroscience, found the effects on short-term memory lasted for at least 50 minutes.

The findings could result in a headset older people wear to ‘turbo-charge’ their failing memories or lead to a future treatment for dementia.

Dr James Pickett, head of research at the Alzheimer’s Society, said: ‘Deep-brain stimulation, a surgical procedure used in Parkinson’s, is proof of principle that this approach may one day be fruitful for dementia.’