How to Save Your Brain's Memory While Asleep
Our memory is one of the most important
things for us—not only as a reminder of our past but also as a
foundation of who we are, and without it, it is very difficult to manage
in the world. As evidence, consider the hundreds of thousands of people
suffering from age-related diseases that affect memory. Therefore,
researchers are working day and night to find solutions to these
cognitive problems, approaching the issue from different directions. One
new and surprising direction comes from the pace of our breathing
during sleep. For the first time, researchers have identified the effect
of our breathing rate during sleep on memory consolidation, with
significant implications for those suffering from sleep-related
breathing disorders.
Breathing synchronizes brain waves that
support memory consolidation
The research in question was conducted at Massachusetts General Hospital
in Boston and by researchers at Northwestern University in Illinois.
According to the researchers, our breathing during sleep acts like an
orchestra conductor in "playing" the brain waves that enhance memory
during sleep. This is the first time that the breathing process has been
linked to the brain waves in the hippocampus—the part of the brain that
plays a significant role in memory and navigation. In this part of the
brain, there are three types of waves related to memory consolidation:
slow waves, sleep spindles, and hippocampal ripples. Scientists knew
these waves were connected to memory, but not what drives them.
"To strengthen memory, three types of brain
waves are generated and synchronized in the hippocampus during sleep,
but until now, we believed they occurred at random times," says
Christina Zelano, one of the study's authors and a professor of
neuroscience at Northwestern University. "We discovered that they are
coordinated by our breathing rate." The researchers found that brain
waves are generated at specific times within the breathing cycle,
suggesting that breathing during sleep is crucial for setting the
correct rhythm for memory consolidation.
What does this mean for people with sleep-related breathing problems?
These findings have significant implications for anyone suffering from
sleep-related breathing disorders, such as sleep apnea—a condition
previously linked to memory consolidation issues. Even in ancient Rome,
it was understood that memory is "written" in the brain during sleep. In
his writings, rhetorician Quintilian noted how a good night's sleep
strengthens memory, describing what we now call "memory consolidation."
"When we sleep, our brain replays experiences from the day," explains
Andrew Sharif, a postdoctoral researcher from Zelano's lab who
participated in the study. He shares his personal experience after
returning from a conference in Reykjavik, Iceland, where he gradually
learned to navigate the city. "The hippocampus plays a significant role
in creating a map of a new area. I would wake up feeling like I knew the
city better. This happened thanks to memory consolidation during sleep,
which is influenced by brain waves, which, in turn, are influenced by
breathing, as we discovered."
Sharif recommends that anyone suffering
from sleep-related breathing problems seek treatment and solutions.
"When we don't sleep enough, our brain suffers. It affects cognition,
and we feel foggy," he says. "We also know that issues affecting
breathing during sleep are linked to stroke, dementia, and Alzheimer's,"
he adds.
"If you listen to someone breathing in bed,
you can even tell when they fall asleep, as our breathing rate changes
during sleep. One of the reasons for this is likely that breathing
performs an important task—it coordinates the brain waves associated
with memory."
How can you tell if you have a sleep-related breathing problem?
Unfortunately, most people with sleep apnea are unaware of it, so it is
more likely that your partner will notice and tell you about the
problem, such as if you stop breathing at night or if you snore or
breathe irregularly. You can also go through this list to check for
silent signs of sleep apnea.
If you find that you do suffer from sleep apnea, it is advisable to
consult a doctor. They may recommend treatment options, including weight
loss, adopting a different sleeping position, using a sleep device, or,
in severe cases, surgery. In general, it is advisable to avoid alcohol
or unnecessary sedatives before bed and try not to sleep on your back,
as this position can make breathing more difficult for those with
sleep-related breathing issues.