A US study into the sleep patterns has found direct neurological differences between heavy and light sleepers, based on the production of brainwaves known as ‘spindles’. The Harvard Medical School research, published in Current Biology, tested twelve participants over a period of three nights. On the first night, they were given a comfortable and quiet sleep-friendly environment, while on the second and third nights a series of sounds ranging from ringing phones and talking to jet engines were played into their rooms.
According to the results, it was found that participants who produced greater and more frequent levels of spindles - high frequency brain waves – were more capable of ignoring the sounds and continuing their sleep, compared to those producing less spindles who were woken by many of the sounds.
“We found that by measuring brain waves during sleep, we could learn a lot about how well a person’s brain can block the negative effects of sounds,” said lead researcher Dr. Jeffrey Ellenbogen. “The more sleep spindles your brain produces, the more likely you’ll stay asleep.”
The study went on to suggest that the sound-tolerating performance of spindles is related to the part of the brain in which they are generated, the thalamus, which deals with sound and sensory information prior to entering the perceptive areas of the brain that create reactions.
The results have sparked a host of speculative queries into the science of sleep, including whether it is possible to artificially stimulate the production of spindles to enable better sleep in noisy environments, as well as implications into sleep’s role in memory formation and learning.