The brain can age faster than the body - and it shows in dreams

The researchers analysed data from almost 7,000 people aged 40 to 94.

Using machine learning algorithms, they estimated "brain age" based on brain waves in sleep.

The participants were then followed from 3.5 to 17 years.

Details

If the "brain age" was higher than the actual age, the risk of dementia increased.

Moreover:

• every additional 10 years increased the risk by about 40 per cent

If the brain was "younger," however, the risk was lower.

Scientists explain that during sleep the brain shows a more accurate picture of its state.

Especially important:

• deep sleep
• rapid bursts of activity related to memory

Conventional sleep metrics (such as how many hours a person sleeps) don't give such accuracy.

Why it's important

The method could be a way of early detection of dementia risk.

What's more:

• without complicated procedures
• potentially even with wearable devices

Scientists emphasise that:

• sleep quality is linked to brain health
• treating sleep disorders can improve brain function

But there is no "quick fix" - it's lifestyle in general that matters.

The discovery could help:

• detect dementia risk at an early stage
• better understand how the brain ages
• use sleep as a diagnostic tool

Source

The study was conducted by scientists from the University of California at San Francisco and US medical centres.

The results are published in the journal JAMA Network Open.