It also found that other forms of stimulation produce different types of brain waves.
The study included 31 people whose brain waves were monitored while they watched humorous, spiritual or distressing video clips. While watching the humorous videos, the volunteers' brains had high levels of gamma waves, which are the same ones produced during meditation, researchers found.
During the spiritual videos, the participants' brains showed higher levels of alpha brain waves, similar to when a person is at rest. The distressing videos caused flat brain wave bands, similar to when a person feels detached, nonresponsive or doesn't want to be in a certain situation.
Researchers were led by Lee Berk, an associate professor in the School of Allied Health Professions, and an associate research professor of pathology and human anatomy in the School of Medicine, at Loma Linda University, in California.
The study was scheduled to be presented Sunday at the Experimental Biology meeting held in San Diego. The data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.
"What we have found in our study is that humor associated with mirthful laughter sustains high-amplitude gamma-band oscillations. Gamma is the only frequency found in every part of the brain," Berk said in a university news release.
"What this means is that humor actually engages the entire brain -- it is a whole brain experience with the gamma wave band frequency and humor, similar to meditation, holds it there; we call this being 'in the zone,'" Berk explained.
He said that with laughter, "it's as if the brain gets a workout." This effect is important because it "allows for the subjective feeling states of being able to think more clearly and have more integrative thoughts," Berk said. "This is of great value to individuals who need or want to revisit, reorganize or rearrange various aspects of their lives or experiences, to make them feel whole or more focused."