U-M To Explore Sleep, Biological Rhythms, Mental Health Links

Armen Hareyan's picture

One of the world's first laboratories devoted solely to research on how sleep and biological rhythms influence depression, substance abuse and other aspects of mental well-being has opened at the University of Michigan Health System.

The U-M Sleep & Chronophysiology Laboratory, based at the U-M Depression Center, welcomed the first research volunteers to its new eight-bed facility this month, and is seeking many more participants for a number of research studies.

And even though the comfortable beds, fluffy down comforters and muted lighting make it look more like a cozy hotel than a research lab, the new facility is home to a number of highly scientific studies on sleep and the daily cycles known as circadian rhythms.

Two of the bedrooms, in fact, are located within suites that may be unique in the world. Called Temporal Isolation Labs, they're designed so that a research volunteer can be closed off entirely from the outside world, unable to tell what time of day it really is.

These suites are specially equipped with banks of lights on the walls and ceiling that can be adjusted precisely by the center's staff to simulate all times of day or night. This can allow a volunteer's innate circadian rhythms -- patterns of rest and activity in both body and mind -- to be monitored or even altered temporarily. The facility can also be used for light therapy to combat problems such as depression.

Now that the laboratory has opened, on the second floor of the Rachel Upjohn Building on U-M's East Medical Campus, director Roseanne Armitage, Ph.D., foresees that her team and colleagues will be able to discover a wealth of new knowledge about how the mind, body and brain interact to produce sleep irregularities and off-kilter circadian rhythms.

"Already, we know that people with depression, seasonal affective disorders, anxiety disorders, alcoholism, and many more conditions suffer terrible disruptions to their sleep patterns, and that in turn, a lack of good-quality sleep worsens their conditions," says Armitage, a professor of psychiatry at the U-M Medical School. "But there are so many unanswered questions about why this happens, how early in life it begins, and how it might be treated or prevented. This lab will help us do just that."


In all, about 80 percent of adults and teens with depression report that they have severe sleep disturbances, and those with prolonged sleep problems also tend to have worse depression over time, and a higher risk of committing suicide.

Conversely, having even a two-week period of insomnia is associated with a higher risk of developing depression later in life. Sleep problems also interfere with recovery from alcohol dependence and postpartum depression, and in children can be a risk factor for later depression.

Armitage, and the center's associate director Robert Hoffmann, Ph.D., have been studying sleep, circadian rhythms and mood disorders for decades, including the past five years at U-M. But the new facility doubles the space for their laboratory team, and other U-M researchers, to perform such studies in infants, children, teens and adults.

The new sleep lab complements U-M's Sleep Disorders Center, which operates outpatient sleep-disorders treatment clinics and two facilities where patients can have overnight sleep tests to diagnose sleep-breathing problems such as sleep apnea, to detect other sleep disorders, or to take part in clinical trials. Psychologist Todd Arnedt, Ph.D., a member of the faculty at both the Sleep Disorders Center and the new sleep research lab, and Director of the Behavioral Sleep Medicine Program, specializes in treating sleep disorders through cognitive behavioral techniques.

The new lab will be staffed seven days a week, with volunteers arriving in the early evening through a special secure entrance and staying until morning, when they can shower and have breakfast before heading to work, home or school. Some might come for several nights in a row, while Temporal Isolation volunteers might stay for several days or even weeks.

Each volunteer has his or her brain waves monitored and recorded overnight, using a technique called electroencephalography or EEG, which can monitor brain activity through small electrodes pasted temporarily to the face and scalp, and linked to a sandwich-sized portable digital recorder. Some volunteers may also wear wristwatch-like devices called actigraphs during the day, to measure their movements and light exposure.

The researchers can then look at all the collected data to see if, for example, a person's circadian rhythms are out of sync with normal clock time and the daily cycle of day and night -- or if their patterns during different sleep stages are abnormal.

Research by the U-M group and others has already revealed that adolescents with depression exhibit highly irregular brain-wave patterns during sleep, and so do teens who are at risk of depression because they have a family history of it. Even babies born to mothers who have depression appear to have altered sleep and circadian rhythms, the team has found.