Brain Imaging Studies Link Sleep Disorders to Structural Changes in Thalamus
A team of investigators at Florida International University has discovered that various kinds of sleep disorders correlate with physical alterations in brain areas that govern attention, motivation, and decision-making. Published in the journal Scientific Reports, the research combines findings from 57 brain imaging studies involving adults to examine how disrupted sleep connects to differences in brain structure.
An estimated 50 million to 70 million Americans experience sleep disorders. The analysis from the FIU Center for Children and Families focused on two broad groups of conditions to determine whether they share similar neural patterns or exhibit distinct structural differences.
Dyssomnias and Parasomnias Share Reductions in the Pulvinar Region
Both major groups of sleep disorders were associated with reductions in the thalamus, a deep brain structure that processes information and sustains attention. Specifically, the analysis identified changes in the pulvinar, a region that helps the brain direct attention toward important information and manage cognitive control.
“Most research looks at sleep disorders one at a time,” said Katharine Crooks, a recent FIU cognitive neuroscience doctoral graduate and lead author of the study. “By looking across many studies, we found shared patterns in the brain that help explain why sleep problems can impact focus, decision-making and everyday functioning.”
These affected neural networks help regulate thoughts and actions during daily tasks. Variations within these systems can shed light on why individuals dealing with sleep disorders frequently encounter delayed responses, trouble with making choices, and an increased chance of making mistakes or getting into mishaps.
Parasomnias Show Distinct Alterations in the Posterior Cingulate Cortex
While both categories showed overlapping structural patterns, researchers discovered distinct differences associated specifically with parasomnias. Conditions such as sleepwalking, nightmare disorder, and sleep terrors involve unusual events or behaviors that interrupt normal sleep cycles.
Individuals with parasomnias showed structural changes in the posterior cingulate cortex, a region involved in motivation, decision-making, and emotional regulation. Matthew Sutherland, a cognitive neuroscientist at FIU and senior author of the study, noted that bringing results from multiple studies together provides a clearer picture of how sleep disorders affect brain structure and function.
In contrast, dyssomnias—which include insomnia and sleep apnea—did not display a consistent pattern of structural changes found exclusively within that category. The FIU team plans to examine individual parasomnias, including REM sleep behavior disorder, in greater detail to understand how these conditions relate to brain changes.
Frequently Asked Questions About Sleep Disorders and Brain Structure
What specific brain regions are affected by sleep disorders?
Both dyssomnias and parasomnias are associated with structural reductions in the thalamus, specifically in a region called the pulvinar. Parasomnias show additional changes in the posterior cingulate cortex.
Which types of sleep disorders were included in the FIU research?
The study analyzed two broad groups: dyssomnias, which include insomnia and sleep apnea, and parasomnias, which include sleepwalking, nightmare disorder, and sleep terrors.
Does disrupted sleep cause these physical changes in the brain?
While the investigation uncovered links connecting sleep conditions to variations in brain anatomy, it remained unclear whether poor sleep directly brings about these modifications, if pre-existing neurological differences predispose individuals to sleep issues, or if both phenomena take place simultaneously.
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