7 Findings from the latest sleep research
Since the 1800s, sleep has fascinated scientists across the globe. Sleep has been studied extensively with journals dedicated to unearthing the latest medical science behind rest. Experts have expanded on this field of study to make links to neurology and cardiovascular health, among others.
What does the latest sleep research reveal about our precious rest? Take a look.
Your brain takes a bath during sleep
Did you know that your brain gets a cleansing bath while you sleep? During deep sleep, cerebrospinal fluid (CSF) is released to clean out ‘molecular dirt’. This is made up of old brain cells which need to be moved out of the brain so regeneration of new cells can take place. According to The Scientist, this research further ties into the importance of restful sleep to regenerate the cells of the body in its different forms.
While scientists are still studying how this brain bath works, research has shown that the structure of the brain changes drastically during sleep as neural activity slows down. While memories are consolidated and new information processed, it also appears that interruptions to sleep have a connection to psychiatric and neurodegenerative conditions.
There is a link between sleep apnea and Alzheimer’s
Sleep apnea is a sleep disorder where a person stops breathing because of a blockage in their airways. Once the brain receives a signal from the respiratory system that there is a lack of oxygen, the person may wake up gasping for air then go back to sleep again. This usually happens intermittently throughout the night. People with sleep apnea are at risk of developing other medical complications such as high blood pressure, stroke and heart disease.
There are 43,8m people who live with Alzheimer’s globally. A 2020 study of 127 people over the age of 65 has found a link between sleep apnea and the onset of Alzheimer’s disease. The JAMA Neurology publication details how the study found amyloid plaques and other biological changes which are characteristic of inflammation and Alzheimer’s disease.
The research also team found that 75% of the participants had sleep apnea and there was a high amount of amyloid protein which is a marker for Alzheimer’s disease. According to the scientists, their findings will enable people with sleep apnea to treat it more effectively, reducing their chances of getting Alzheimer’s disease.
Digital CBT is the most cost-effective treatment for poor sleep
Digital Cognitive Behavioural Therapy has come out tops in being the most cost-effective option to treat poor sleep. It is a type of psychotherapeutic treatment that combines identifying destructive thought patterns which influence emotions and sleep.
The Sleep Journal reports that researchers from John Hopkins University, University of California and digital therapeutics provider Big Health held a study with 100,000 participants.
The study took into account how much people were spending on insomnia, health care expenditure and workplace accidents and productivity. The results revealed that digital CBT, represented by the app Sleepio was the best and most cost-effective treatment, clocking in at $681 per person over a six month period.
Andrew Krystal, MD, department of psychiatry, University of California San Francisco School of Medicine said beyond cost, digital cognitive behavioural therapy can help overcome significant barriers to insomnia treatment for millions of people, including limited access to clinicians in rural areas, the lack of trained clinicians and, for others, the lack of awareness of their treatment options.
Sleep mutation genes allow for less shut-eye than normal
A team led by Dr Ying-Hui Fu at the University of California has discovered a second mutation gene that enables the carriers to sleep an average of 4 hours a night without feeling tired the next day. The first mutation gene was found when Fu has conducted research on multiple families who profess to sleep less than an average of 7 hours a night.
Studies on the DNA of the first family found they had a mutation gene called ADRB1. The New Scientist reports that the ADRB1 gene codes for a receptor protein common in a brain region called the dorsal pons, which works to regulate sleep. In the second family, a gene code called NPSR1 was recorded and members of that family reported sleeping for 4,3 and 5,5 hours a night. NPSR1 is said to bind to a protein receptor in the brain known to be involved in arousal and sleep behaviour.
Members of both families have not reported any long-term effects of sleep deprivation, such memory loss, fatigue, lack of concentration, heart disease and stroke. Preliminary studies show their gene mutation also protects them from such illnesses but more research is required.
Meanwhile, scientists have isolated and identified the gene mutations and are seeking to replicate them to help with studies on sleep, possibly making them available as medication in the near future.
Sleep deprivation can affect your memory
Scientists have studied the link between sleep and memory for 100 years but it’s only recently they have discovered how poor quality sleep negatively impacts the brain’s overall functioning capacity.
In 2019, the publication Current Biology reported restless rapid-eye-movement (REM) sleep negatively impacts amygdalae. These are almond-sized nuclei found within the brain temporal lobes. The amygdalae process information and consolidate memories. They link emotions to events within the mind, helping to elicit the relevant emotions associated with memory.
Current Biology further reports people whose sleep was interrupted in the REM sleep phase, woke up the next day showing intense emotion towards events from the previous day. People who got quality sleep including REM sleep, felt the events of the past day were of little significance on the present day. Scientists believe this is key to understanding how sleep deprivation affects us.
The link between Alzheimer’s and the circadian rhythm
When your circadian rhythm is out of sync it can lead to an accumulation of amyloid. These are proteins which begin to show up in the brain and are an early indicator of Alzheimer’s disease.
The circadian rhythm governs the internal clock which influences the timing of internal processes such as when you wake up and when you feel hungry.
In an article on the link between Alzheimer’s and sleep patterns, Dr Erik Musiek, an associate professor of neurology at the University of Washington said an off-kilter circadian clock from disrupted sleep and napping during the day leads to inflammation. Amyloid plaques then begin to form which are precursors to Alzheimer’s disease.
Can your dreams tell the future?
It’s been a fascinating topic of debate for centuries. Can our dreams predict the future? Neurological scientists and sleep researchers have indicated our dreams are made up of the events we experience every day and in the past. Our emotions then fuel these images which end up as dreams. Predictive dreams then become educated guesses, which our minds have processed and sent back to us as prophetic visions.
However, the opposing argument is that dreams have no sound scientific basis as yet and more research needs to be conducted to draw conclusive findings.
In an interview with the Daily Mail, Dr Julia Mossbridge who has been studying precognition for 15 years, says our dreams can tell the future. Dr Mossbridge is a cognitive neuroscientist and experimental psychologist who has shared her findings in a book.
According to Dr Mossbridge, she dreamt of a house fire and this saved her life. The neurological expert believes that our minds prepare us for the future through dreams and that research suggests 15-30 per cent of people have had precognitive dreams.