Special sounds during sleep can improve sleep and boost memory, new research finds.
The gentle sounds were timed to coincide with natural ‘brain waves’: the waves of electrical activity in the brain.
People in the study were able to recall 26% more words they had learned after being exposed to the sounds during sleep.
Dr Phyllis Zee, a study author, said:
“This is an innovative, simple and safe non-medication approach that may help improve brain health.
This is a potential tool for enhancing memory in older populations and attenuating normal age-related memory decline.”
Deep sleep is known to be critical for memory consolidation: the process by which memories are laid down for the long-term.
However, in older adults the amount of time spent in deep sleep typically reduces.
The study compared the acoustic simulation with sham treatments, which acted as a placebo.
Older individuals — who were targeted for the study — showed better sleep and enhanced memory only after the real acoustic stimulation.
The study’s authors explain their conclusions:
“Acoustic simulation that was phase-locked to sleep slow waves in older adults had systematic effects on sleep indices and performance on a declarative memory test.
These results provide the first demonstration that acoustic stimulation alters SWA [slow wave activity or, colloquially, deep sleep] and can enhance word pair recall in older adults.
These results converge with other findings in young adults indicating that acoustic stimulation during sleep is a promising tool for altering SWA and enhancing sleep-dependent memory consolidation.”
The sound waves in the study were timed to coincide with people’s brain waves.
Their brain waves were read in real time and the sounds timed to help synchronise activity across the neurons.
Dr Nelly Papalambros, the study’s first author, said:
“The idea is to be able to offer this for people to use at home.
We want to move this to long-term, at-home studies.”
The study was published in the journal Frontiers in Human Neuroscience (Papalambros et al., 2017).