Jefferson University Hospitals

The most common type of insomnia is secondary insomnia, which occurs in conjunction with another illness or disorder, either physical or mental, or as a side effect of certain medications or substances. Primary insomnia occurs without a coexisting condition, persists for one month or longer and affects approximately a quarter of the adult population.

A new study suggests that a specific neurochemical imbalance found in adults with primary insomnia makes it more difficult for their brains to settle down for sleep.

Many adults suffering from insomnia complain of a “racing mind” and an inability to shut down at night. Researchers now suggest this experience is not just “in your head.” Rather, it’s a result of a decrease in the neurochemical gamma-aminobutyric acid (GABA).

As reported in the medical journal Sleep, people with primary insomnia for more than six months have 30 percent less GABA, a chemical that slows overall activity in many brain areas. According to one of the principal investigators, GABA is reduced in the brain of individuals with insomnia – suggesting overactivity is present not only at the level of excessive thoughts and emotions, but can also be detected at the level of the nervous system.

Read more about the study’s findings, and learn how Jefferson’s Sleep Disorders Center helps in diagnosing and treating a range of sleep problems.