People usually think of insomnia as a problem of the night, but it’s more than that. When you have insomnia, you pay for it during the day. Every task becomes a chore, and learning new things can be a struggle.
New research from sleep investigator Sean P.A. Drummond, associate professor in the psychiatry department at the University of California, San Diego, suggests why insomnia affects us this way. Drummond and colleague Matthew Walker conducted a brain imaging study just published in the journal Sleep and found that the insomniac brain has to work harder than normal to process information in working memory.
“We found that insomnia subjects did not properly turn on brain regions critical to a working memory task and did not turn off ‘mind-wandering’ brain regions irrelevant to the task,” Drummond is quoted as saying in ScienceDaily. “Based on these results, it is not surprising that someone with insomnia would feel like they are working harder to do the same job as a healthy sleeper.”
This the first imaging study to show that working memory—short-term memory associated with immediate conscious perceptual and linguistic processing—is compromised in insomniacs. And pictures don’t lie.
Insomniacs’ Brains Work Harder
There were 50 subjects in all. Half were good sleepers; the other half, insomniacs. The test consisted of sitting in front of a screen and being shown a series letters one at a time. Subjects had to decide if the letter currently displayed was the same as the one presented 0, 1, 2, or 3 letters back. Their brains were scanned during the test to record activity levels in various parts of the brain.
Insomniacs performed as well as good sleepers on the memory task. But their brains had to work harder to do it:
1) As the task got harder, the images showed that good sleepers tapped into more resources within the working memory network of the brain. Insomniacs were unable to do this.
2) As the task got harder, good sleepers experienced reduced activity in parts of the brain normally active when the mind is wandering. Insomniacs did not.
What This Means for Insomniacs
No wonder it can feel like we struggle to do mental tasks that normal sleepers accomplish without great effort. We really are struggling, and struggle leads to exhaustion. Who among us has not complained about that?
The good news is that when scientists can identify measurable deficits in the brain as Drummond and Walker have, these deficits can then become targets of treatment. Insomnia treatments shouldn’t only put us to sleep. They should also help to wake us up.
Does your sleep problem make it harder to commit things to memory?