Scientists have found that a decline in memory as a result of ageing can be temporarily reversed using a harmless form of electrical brain stimulation. The study focused on a part of cognition called “working memory” which is crucial for a wide variety of tasks such as recognising faces, mathematics and navigating a new environment. This is known to steadily decline with age, and is thought to be due to a disconnection between two brain networks known as the prefrontal and temporal regions. In young people, the electrical brain activity in these two regions tends to be rhythmically synchronised but less so in older people.

Two groups were used in the research: one with people aged 20-29 and the other with people aged 60-76. First they were tested with working memory tasks, and the older group was slower and less accurate on the tests. The scientists then subjected both groups to 25 minutes of non-invasive brain stimulation that was aimed to synchronise the two target brain regions by passing gentle pulses of electricity into the brain. The result was that the working memory of the older group improved to actually match the younger group, and the effect lasted for at least 50 minutes after the stimulation. Interestingly, those who had scored the worst in the initial tests, showed the greatest improvement. Whilst more studies are needed to confirm the findings and assess how they might be applied clinically, the results show promise, and could lead to significant improvement of memory in older people, as well as treating disorders such as Alzheimer’s and schizophrenia.