The cat has my tongue this morning, so I'll let the NY Times say it:
A Neuroscientific Look at Speaking in Tongues
The passionate, sometimes rhythmic, language-like patter that pours forth from religious people who “speak in tongues” reflects a state of mental possession, many of them say. Now they have some neuroscience to back them up.
Researchers at the University of Pennsylvania took brain images of five women while they spoke in tongues and found that their frontal lobes — the thinking, willful part of the brain through which people control what they do — were relatively quiet, as were the language centers. The regions involved in maintaining self-consciousness were active. The women were not in blind trances, and it was unclear which region was driving the behavior. To read more, click here...