According to a research, even one night without sleep can cause structural
changes in the brain that are comparable to those that occur as people
age.
A recent research indicates that even one night without sleep can make the
brain appear older, as if it had matured one to two years over night.
After a restful night's sleep, these alterations, however, seem to
vanish.
In the study, researchers used machine learning to determine the "brain
age" of participants' brains using magnetic resonance imaging (MRI) images
taken before and after they had a complete night of slumber. According to
research findings that were released on February 20 in the Journal of Neuroscience, one night of total sleep deprivation causes
brain alterations that are comparable to those that occur after one or two
years of aging.
According to Judith Carroll, an assistant professor of
psychiatry and biobehavioral sciences at the University of California, Los
Angeles who was not engaged in the research, brain age is "a very
fascinating metric in terms of looking at how that alters from the sleep
loss."
A total of 134 participants were divided into four groups for the purposes
of the study: total sleep deprivation (no sleep for one night), partial
sleep deprivation (three hours in bed for one night), chronic sleep
deprivation (five hours in bed each night for five nights), and a control
group. The data were taken from five existing data sets (eight hours in bed
each night). Prior to sleep restriction, each group had at least one night
of baseline sleep during which they slept for eight hours; most groups also
experienced a complete night of recovery sleep.
In order to evaluate how people's brains appeared before and after sleep
deprivation and after a complete night of rest, each person had an MRI
obtained after each night.
Using a machine-learning algorithm dubbed brainageR that was trained on
data from more than 3,000 individuals, the researchers were able to
calculate the apparent ages of the subjects' brains. The freely accessible
program uses a person's brain MRIs to estimate their chronological age based
on the tissue and fluid volume of healthy brains at various ages.
Researchers discovered that brainageR could correctly estimate age within
about four years in previous experiments.
In their latest study, the researchers discovered that brainageR assessed
the participants in the group who slept poorly for one night to be, on
average, one to two years older than initial predictions. These variations
disappeared after a night of rest.
In terms of age forecasts, there were no appreciable variations between the
partial and chronic sleep loss groups and the control group.
These findings are consistent with previous studies on how sleep loss
affects the brain. The distribution of fluid and the amount of gray matter
in the brains of sleep deprived individuals have been shown to alter, among
other things.
According to study senior author Dr. David Elmenhorst, a
professor in the Department of Neuroscience and Medicine at the German
research center Forschungszentrum Jülich, this "widespread shift in brain
morphology... would be caught with this technique of brain age as well."
Importantly, he described the findings as changes that the machine-learning
system mistook for aging rather than real aging.
Carroll said that it is difficult to interpret the study's findings because
this impact was only observed in the group who had experienced complete
sleep deprivation. Even the chronic condition lasts only five days, so I'm
not convinced we can say anything about the long-term consequences of
chronic sleep loss, she said.
The research also had a limited sample size. A bigger sample size,
according to Elmenhorst, might emphasize less significant impacts in the
other groups, such as a few-month increase in brain age. Carroll suggested
that future studies include participants who regularly lack sleep, such as
those who work shifts.
When they are awake all night, "a lot of people really battle to slumber
[during the day]," she said. "I believe it could be really useful and more
informative to do something that looks at this in more detail in those
groups."