The real reason insomniacs can't get to sleep

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Your late-night TV binges may not be the only reason you're having trouble sleeping: An overactive brain could be what's keeping lots of insomniacs up at night, according to a new study published in the journal Sleep.

In this study, researchers recruited 28 adults—18 of whom had insomnia—to see how their brains adapted to new tasks. For the first part of the experiment, study authors sent transcranial magnetic stimulation (TMS) pulses through the participants' brains to determine which directions their thumbs moved naturally when they did this.

Then, the research team spent 30 minutes training people to move their thumbs in the opposite direction without the electric pulses. Finally, they gave participants another round of TMS pulses and instructed them to continue to move their thumbs in this new direction.

It turns out that the insomniacs were more likely to perform these trained thumb movements better than the good sleepers, who had more difficulty fighting their natural urges to move their thumbs in a certain direction.

So what does this mean? Insomniacs' brains may constantly be in a hyper-aroused state, says study author Rachel Salas, M.D., assistant professor of neurology at the Johns Hopkins School of Medicine. When the brain is always "on," you're better able to learn simple tasks—but that also means you'll probably have difficulty shutting down mentally when bedtime rolls around.

Certain chemicals in the brain may play a role, too: In this study, higher levels of glutamate, a neurotransmitter in the brain, were linked to this aroused state of mind in insomniacs. More work is needed to determine whether a lack of sleep causes the brain to become hyper-aroused or if some people are just genetically predisposed to having an overactive mind.

If you suffer from insomnia or occasional sleep trouble, try one of these tricks to help you fall asleep faster:

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