Brains of insomniacs wired differently
Insomnia doesn’t just happen at night, but is instead more of a 24/7 disorder, according to a new study published Friday in the journal Sleep.
Researchers for the study found that the brains of insomniacs are actually more active than the brains of those who sleep soundly.
Accordingly, the root cause of insomnia, and the inability to sleep that it causes, may be due to how the brain is wired and the resulting impact this has on the mind – regardless of the time of day.
Lead study author, Dr. Rachel Salas, an assistant professor of neurology at the Johns Hopkins University School of Medicine, compared an insomniac’s brain wiring to a light switch that’s always on; thus, causing their brains to remain continually active.
Dr. Salas initial theory was that those who slept soundly would be the ones whose brains were more active and alert, so she launched a study to prove it, which involved two different groups of volunteers, 18 chronic insomniacs and 10 sound sleepers, both of which were compared in the study.
The study used transcranial magnetic stimulation (TMS) to examine activity in the brains of each volunteer because TMS allowed the researchers to target a specific location in the motor cortex of the brain, which controls movements of the thumb.
As a result, each time a magnetic pulse was sent through a volunteer’s scull and into their brain, it sparked an involuntary twitching of their thumb.
After receiving 65 magnetic pulses, the volunteers were then instructed to do the following:
Practice moving their thumbs on their own in the opposite direction from the one that was involuntarily sparked by the TMS.
In other words, if their thumbs were involuntarily triggered to flick up and right, they were to try moving their thumbs in the opposite direction, which would be down and left.
Following this practice exercise, the researchers turned the TMS back on to find out if the brains of the volunteers learned to move their thumbs in the new direction. The idea was to find out if their brains were able to rewire connections. So if their thumbs flicked in the new direction when the TMS was turned back on, it would suggest that such rewiring was possible.
As this pertains to insomniacs is important because people who can’t sleep are typically fatigued during the day and often have problems concentrating and accomplishing tasks efficiently. Therefore, Dr. Salas and the research team were expecting that the group of insomniacs would not perform the thumb-switching exercise as well as the sound-sleeping group.
But they were wrong.
Indeed, the insomniacs actually were better at rewiring their brain after they practiced moving their thumbs in the opposite direction of the one involuntarily sparked by the magnetic pulses from the TMS.
As Dr. Salas pointed out, such ability is usually seen as a positive thing, but too much of a good thing may not be positive, especially with insomniacs who may have performed well because they were hyper-aroused and had increased excitability.
In this regard, Dr. Salas noted that brain excitability doesn’t necessarily mean that insomniacs are naturally higher strung or more hot blooded. Rather, she said that it simply means that their brains are sparking more.
SOURCE: Journal SLEEP, Increased Use-Dependent Plasticity in Chronic Insomnia, Dr. Rachel Salas, et al. March 1, 2014 (http://dx.doi.org/10.5665/sleep.3492)