The highly respected 1972 study of John P. Kildahl (The Psychology
of Speaking in Tongues) concludes that "from a linguistic point
of view, religiously inspired glossolalic utterances have the same
general characteristics as those that are not religiously inspired." In
fact, glossolalia is a "human phenomenon, not limited to Christianity
nor even to religious behavior." (Dictionary of Pentecostal and
Charismatic Movements by Spittler, P. 340).
Experts in the field of linguistics have diligently studied the phenomenon of glossolalia over a period of many years. One of the early investigations was made in the early 1960's by Eugene A. Nida. He provided a detailed list of reasons why glossolalia cannot be human language. Another early study, that of W.A. Wolfram in the year 1966, also concluded that glossolalia lacks the basic elements of human language as a system of coherent communication.
In a massive study of glossolalia from a linguistic perspective by Professor William J. Samarin of the University of Toronto's Department of Linguistics published after more than a decade of careful research, he rejected the view that glossolalia is xenoglossia, i.e. some foreign language that could be understood by another person who knew that language. Samarin concluded that glossolalia is a "pseudo-language." He defined glossolalia as "unintelligible babbling speech that exhibits superficial phonological similarity to language, without having consistent syntagmatic structure and that is not systematically derived from or related to known language." (William J. Samarin, "Variation and Variables in Religious Glossolalia," Language in Society, ed. Dell Haymes, Cambridge: Cambridge University Press, 1972 pgs. 121-130)
Felicitas D. Goodman, a psychological anthropologist and linguist, engaged in a study of various English - Spanish - and Mayan-speaking Pentecostal communities in the United States and Mexico. She compared tape recordings of non-Christian rituals from Africa, Borneo, Indonesia and Japan as well. She published her results in 1972 in an extensive monograph (Speaking in Tongues: A Cross-Cultural Study in Glossolalia by Felecitas D. Goodman, University of Chicago Press, 1972).
Goodman concludes that "when all features of glossolalia were taken into consideration--that is, the segmental structure (such as sounds, syllables, phrases) and its suprasegmental elements (namely, rhythm, accent, and especially overall intonation)-- she concluded that there is no distinction in glossolalia between Christians and the followers of non-Christian (pagan) religions . The "association between trance and glossolalia is now accepted by many researchers as a correct assumption," writes Goodman in the prestigious Encyclopedia of Religion (1987).
Goodman also concludes that glossolalia "is, actually, a learned behavior, learned either unawarely or, sometimes consciously." Others have previously pointed out that direct instruction is given on how to "speak in tongues," ie. how to engage in glossolalia.
In fact, it has been found that the "speaking in tongues" practiced in Christian churches and by individual Christians is identical to the chanting language of those who practice voodoo on the darkest continents of this world .
Those who speak in tongues are also becoming involved in "holy laughter" - laughing uncontrollably, falling down on the ground, rolling around, having seizure-like activity, being struck dumb, or being "slain in the spirit."