Poor sleep does not affect every adult brain the same way. Researchers including psychologists from Binghamton University, State University of New York analyzed resting brain scans from two large samples totaling more than 1,300 people and found that the connectivity patterns tied to poor sleep quality differed according to a participant's age and biological sex.
The work, titled "Sleep quality is associated with default mode and salience network connectivity differently across age and sex," was published in Neurobiology of Aging. Co-authors include Binghamton psychology graduate student Sepehr Gourabi and Associate Professor of Psychology Ian McDonough, along with Selene Tan, Matthew Cribbet and Jeanne Cundiff of The University of Alabama. The two networks under study, the default mode network and the salience network, are among the brain's major communication systems and are measured here by how their regions coordinate while a person is simply at rest.
The researchers' summary of the older-adult findings is blunt: the poorly slept older brain, they report, "looks like it is suffering from a general breakdown in its sleep-regulation systems." That framing matters because sleep problems are common in later life and are often treated as a nuisance rather than a signal. If disrupted sleep tracks with measurable shifts in how brain networks talk to each other, and if those shifts look different at 30 than at 70, then sleep quality becomes a variable worth measuring carefully in aging research rather than averaging across everyone.
The age and sex differences are the practical takeaway for future work. Studies that lump all adults together may wash out real effects, or attribute to sleep something that is really about who is being studied. These are associations drawn from brain imaging at a single point in time, so they describe patterns rather than establish that poor sleep causes the connectivity changes observed.