Sleep disorders, including insomnia, sleep apnea, sleepwalking, and nightmares, are associated with structural changes in areas of the brain responsible for attention, decision-making, and emotional regulation. This conclusion was reached by researchers at Florida International University (FIU), who analyzed the results of 57 scientific studies using neuroimaging.
The findings were published in the scientific journal Scientific Reports, which is part of the Nature Portfolio publishing group. An article about the study was also published by ScienceDaily on November 7, 2026.
The authors found that different sleep disorders may be accompanied by both common and specific changes in brain structure. This helps to better understand why sleep problems are often associated with memory impairment, slower reaction times, difficulties concentrating, and changes in emotional state.
Scientists Analyzed 57 Brain Studies
Researchers from the Center for Children and Families at Florida International University conducted a meta-analysis of 57 studies that assessed the brain structure of adults using neuroimaging techniques.
Unlike most previous studies, which focused on individual disorders, the researchers compared two major groups of sleep disorders.
The first group, dyssomnias, includes insomnia, sleep apnea, and other conditions that make it difficult to fall asleep, maintain sleep, or achieve a normal duration of sleep.
The second group, parasomnias, includes sleepwalking, recurring nightmares, night terrors, and other unusual phenomena that occur during sleep.
Of the 57 scientific studies analyzed, 40 focused on dyssomnias and 17 on parasomnias.
The researchers found that different sleep disorders are characterized by changes in the thalamus, a brain structure involved in processing sensory information, regulating attention, and supporting complex cognitive processes.
The scientists paid particular attention to the pulvinar of the thalamus, which helps the brain identify important information, control attention, and coordinate task performance.
In people with sleep disorders, the researchers identified signs of reduced tissue volume in this region.
According to the authors' hypothesis, such structural characteristics may be associated with slower reaction times, difficulties in decision-making, and an increased risk of errors in everyday activities.
Nightmares and Sleepwalking Have Additional Characteristics
Certain structural changes were identified in people with parasomnias.
In particular, the researchers found changes in the posterior cingulate cortex, which is involved in motivation, evaluating the outcomes of one's own actions, decision-making, and emotional regulation.
This region is connected to brain networks responsible for the formation of behavioral responses, reward perception, and a person's emotional state.
According to the researchers, the identified characteristics may partly explain why parasomnias are sometimes accompanied by changes in mood, behavior, and the ability to control emotions.
At the same time, for dyssomnias, including insomnia and sleep apnea, the scientists were unable to establish a single specific pattern of structural changes characteristic exclusively of this group.
This indicates the complexity of the neurobiological mechanisms underlying sleep disorders and the need for further research into individual conditions.
Findings May Help Improve Diagnosis
The senior author of the study, Florida International University cognitive neuroscientist Matthew Sutherland, noted that combining the results of numerous scientific studies makes it possible to more accurately identify brain regions associated with different sleep disorders.
The study's lead author, Katharine Crooks, emphasized that identifying common structural patterns may help explain the impact of sleep problems on attention, decision-making, and everyday performance.
The scientists hope that the findings will contribute to the future development of more accurate diagnostic methods and personalized approaches to treating sleep disorders.
In particular, a promising direction may be the development of therapeutic approaches aimed not only at normalizing sleep but also at protecting the brain networks that support cognitive and emotional functions.
Does Poor Sleep Cause Changes in the Brain?
The study's authors emphasize an important limitation of their findings: the identified association between sleep disorders and structural characteristics of the brain does not prove a cause-and-effect relationship.
It remains unknown whether prolonged sleep disturbances themselves lead to changes in brain structures or whether certain brain characteristics increase the likelihood of developing such disorders.
It is also possible that both mechanisms operate simultaneously.
In addition, the study combined findings from research using different methodologies and patient groups. This limits the possibility of using the identified patterns to diagnose a specific individual.
In the future, the scientists plan to investigate individual types of parasomnias in greater detail, particularly sleepwalking and rapid eye movement sleep behavior disorder (REM sleep behavior disorder).
According to estimates cited by the researchers, approximately 50–70 million people in the United States suffer from various sleep disorders. Sleep problems remain an important public health issue because of their potential impact on work performance, psychological well-being, and safety in everyday activities.
Sources: Original study in Scientific Reports dated February 26, 2026, Florida International University report dated July 15, 2026, ScienceDaily dated November 7, 2026.
