Friday, January 12, 2007

A personal recollection and some neurological ruminations on glossolalia

When we were children growing up in Bangalore, India, my parents would pack my brother, sister and me down to our ‘native-place’ (a small town in Kerala, the place where my parents grew up) to spend time with our grand parents, uncles and aunts. These trips were a mixture of discovery, exploring nature, wide grassy lands with intrusive coconut trees and great food prepared from produce grown in and around our home. Every once in a while, I would venture out to the boundaries of the large tracts of land that was part of my mothers ancestral property. On occasions, I used to distinctly remember hearing a distant rhythmic wailing of human voices sounding very eerie, intriguing and somewhat painful. I resolved to ask my cousin about the origin of these mysterious voices. On querying, he explained to me that they were a denominational sect of Pentecostal Christians praying and seemingly in a trance. I was intrigued. I decided in all my infinite wisdom that this was a pretty strange way to pray… so, I decide to explore the boundaries a little more and find out more about this ‘prayer’. I remember being frightened and brave at the same time – frightened as to what I was going to uncover and brave because I was doing this all by myself. Presently I crossed the boundaries of our lands and followed the direction of the chanting sounds until I came upon a clearing with a stark white stucco house with barred windows and a large shut wooden door. At this time I remember the voices being very loud, incoherent, and rhythmic but making no sense whatsoever. I noticed that if I tried hard enough, I could venture out and peep through a tiny slit in one of the closed windows. I decide that this was my chance. I crept up to the window and peered inside. It took some time for me to adjust to the dim kerosene lamp based lighting inside, but I saw about 20 -25 locals sitting in a group, arms and bodies flailing, chanting a strange language that made no sense to me. Some of the women in the group had their hair loose and it added to the eeriness of the spectacle. I decided that if I stayed on and spied on this strange group any longer, I may be caught and transformed into one of the members of the group (which was a prospect I definitely was not relishing). Quietly and quickly I ran away and remember not be able to sleep well that night with all kinds of strange images floating around in my head.

I am sure that it made quite an impression in my head for me to remember in this detail what happened roughly 25 years ago, but I what I described above is now termed as ‘glossolalia’. There is nothing strange or mystical about glossolalia – in fact some people say it has therapeutic properties (I am not so sure of that). I decided to write on glossolalia because of the fact that something as unreasonable or irrational as this can now be explained through neuroscience.

Glossolalia or ‘speaking in tongues’ is an unusual mental state associated with certain religious orders where the subject goes into a trance like state and produces speech that is not semantically linked and not part of the normal language repertoire of the individual. In most cases this can be described as religious singing state where the words of the songs have no structure, syntax, morphology, semantics or known language origins. It is now known that Glossolalia has been practiced by Christian as well as non-Christian denominations for thousands of years (some examples are Shamans of Sudan, the aborigines of South America and Australia and Tibetan monks). For an extensive list see here.

It is also known that certain neurological deficits like Wernicke’s aphasia, epileptic seizures of the temporal lobe and cataphasia also produce glossolalia like symptoms (although present studies have shown that most of the religious practitioners show no known neurological deficits).
Researchers at UPenn have published a neuro-imaging study on glossolalia, and have found the following:

1. Decreased activity in the frontal lobes (entirely in line with the experience – the frontal lobes maintain our sense of conscious control and thinking and the phenomenon of glossolalia shows a marked reduction of intentional control leading to low levels of activity in these lobes )

2. Decreased activity in the left hemispheric structures (our left lateral hemisphere specifically the left temporal lobe behind your ears is dominant in about 90% of individuals as they go about the mechanics of meaningful language construction, but in a ‘glossolaliac’s’ case the language is really not produced, the sounds are non-structured and non-semantic and hence lesser activity in the left lateral hemisphere)

3. The studies also showed a dip in the activity of a region called the left caudate. The caudate area is involved in motor and emotional control, so it may be that practitioners, while mindful of their circumstances, cede some control over their bodies and emotions.

4. They also noticed a shift in thalamic activity when the subject changed from a normal singing mode to a glossolaliac phase. The thalamus is responsible for relaying large amounts of cortical and cortical-subcortical neuronal information. This shift might be indicative of the sense of control alteration in which practitioners no longer feel as if they are willfully making the vocalization.

Of course this is just the first imaging study of glossolalia, but studies like this once again demonstrate that what looked like seemingly bizarre behavior could be fairly easily explained when they are looked at from a scientific perspective.

It is also interesting to note the following from this paper (more of a psychiatric treatment to this phenomena) :
The experience of glossolalia is always connected with the feeling of euphoria, relaxation and altered state of consciousness. An explanation of the positive neuropsychological relaxing effect of glossolalia could be derived by looking at the activity of limbic system and anterior hypothalamus. This activity is mediated by acetylcholine, which activates parasympathetic pathways, leading to the reduction in autonomous and skeletal-muscular tension and metabolic activities that protect the organism from the stress and decrease the cerebral cortical activity.

Please see this paper for some more interesting related stuff:
Meditation States and Traits: EEG, ERP, and Neuroimaging Studies by B. Rael Cahn and John Polich

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