Study shows that insomnia may cause dysfunction in emotional brain circuitry

(Press-News.org) DARIEN, IL – A new study provides neurobiological evidence for dysfunction in the neural circuitry underlying emotion regulation in people with insomnia, which may have implications for the risk relationship between insomnia and depression.

"Insomnia has been consistently identified as a risk factor for depression," said lead author Peter Franzen, PhD, an assistant professor of psychiatry at the University of Pittsburgh School of Medicine. "Alterations in the brain circuitry underlying emotion regulation may be involved in the pathway for depression, and these results suggest a mechanistic role for sleep disturbance in the development of psychiatric disorders."

The study involved 14 individuals with chronic primary insomnia without other primary psychiatric disorders, as well as 30 good sleepers who served as a control group. Participants underwent an fMRI scan during an emotion regulation task in which they were shown negative or neutral pictures. They were asked to passively view the images or to decrease their emotional responses using cognitive reappraisal, a voluntary emotion regulation strategy in which you interpret the meaning depicted in the picture in order to feel less negative.

Results show that in the primary insomnia group, amygdala activity was significantly higher during reappraisal than during passive viewing. Located in the temporal lobe of the brain, the amygdala plays an important role in emotional processing and regulation.

In analysis between groups, amygdala activity during reappraisal trials was significantly greater in the primary insomnia group compared with good sleepers. The two groups did not significantly differ when passively viewing negative pictures.

"Previous studies have demonstrated that successful emotion regulation using reappraisal decreases amygdala response in healthy individuals, yet we were surprised that activity was even higher during reappraisal of, versus passive viewing of, pictures with negative emotional content in this sample of individuals with primary insomnia," said Franzen.

The research abstract was published recently in an online supplement of the journal SLEEP, and Franzen will present the findings Wednesday, June 5, in Baltimore, Md., at SLEEP 2013, the 27th annual meeting of the Associated Professional Sleep Societies LLC.

The American Academy of Sleep Medicine reports that about 10 to 15 percent of adults have an insomnia disorder with distress or daytime impairment. According to the National Institute of Mental Health, 6.7 percent of the U.S. adult population suffers from major depressive disorder. Both insomnia and depression are more common in women than in men.

### For a copy of the abstract, "Elevated amygdala activation during voluntary emotion regulation in primary insomnia," to arrange an interview with Dr. Franzen or an AASM spokesperson, or to register for a press pass to attend SLEEP 2013, please contact AASM Communications Coordinator Lynn Celmer at 630-737-9700, ext. 9364, or lcelmer@aasmnet.org.

A joint venture of the American Academy of Sleep Medicine and the Sleep Research Society, the annual SLEEP meeting brings together an international body of more than 5,500 leading clinicians and scientists in the fields of sleep medicine and sleep research. At SLEEP 2013, more than 1,300 research abstract presentations will showcase new findings that contribute to the understanding of sleep and the effective diagnosis and treatment of sleep disorders such as insomnia, narcolepsy and sleep apnea.

The American Academy of Sleep Medicine considers sleep disorders an illness that has reached epidemic proportions. Board-certified sleep medicine physicians in an AASM-accredited sleep center provide effective treatment. AASM encourages patients to talk to their doctors about sleep problems or visit http://www.sleepeducation.com for a searchable directory of sleep centers.