Research suggests primary insomnia may be associated with specific neurochemical deficiency.

 HealthDay (6/9, Thomas) reported that, according to a study presented at a sleep conference, “adults with primary insomnia have a neurochemical abnormality that makes it difficult to ’shut down’ the mind at night for sleep,” Harvard researchers said. “Unlike most cases of insomnia, primary insomnia can’t be attributed to a psychiatric, medical or environmental cause.” For the study, the team “measured the levels of gamma-aminobutyric acid (GABA) in 16 adult men and women with primary insomnia and 16 men and women deemed normal sleepers.” They found that “people who had suffered from primary insomnia for more than six months had 30 percent lower levels of GABA,” which is “the most common inhibitory transmitter in the brain,” slowing “overall activity in many brain areas.” The authors speculated that “primary insomnia is the result of a neurobiological state of hyperarousal, and that this state remains throughout the day and night, affecting the individual’s mind and body.” Notably, “about one-quarter of people with insomnia have this type.”