In epilepsy, a seizure begins with just a few neurons that – for reasons that still elude medical professionals – get overstimulated. That excess stimulation then gets passed through the synapses to other neurons, which become overstimulated in turn, and the spread of that intense chaotic activity produces the behavioral features of a seizure. These disruptive bursts of activity also damage the brain, and can lead to cognitive deficits, so anyone with epilepsy will take great pains to avoid seizures, by taking medications or adopting fat-rich diets – and, of course, avoiding any known epileptic triggers. This could mean no rapidly flashing TV screens (of Pokemon seizure infamy), no music (not any easy feat)….and just to be safe, perhaps no meditation.
This the theory proposed by Harinder Jaseja in a pair of theoretical paper published in Medical Hypotheses. The first, from 2005, identifies two major reasons to think that meditation could set an epileptic up for a seizure. First, meditation alters the pattern of how neurons fire, by enhancing what’s called the alpha rhythm – the distinct way our neurons fire when we are awake but relaxed, exactly as meditation would hope to achieve. Except, that pattern might veer into “hypersynchrony”, which is too many neurons firing simultaneously, which is a seizure. Second, Jaseja suggests that meditation might increase the production of the neurotransmitters glutamate and serotonin, which have also been linked to seizures. (Concerns about glutamate triggering seizures have lead to the suggestion that people with epilepsy should avoid MSG – full name, mono sodium glutamate).
A year later, Jaseja published again, elaborating on some of these ideas. The mechanisms behind the potential links of glutamate and serotonin are explained in slightly more detail, to better connect the dots between why and how they might be enhanced by meditation and might contribute to seizures. The details are best left for the neuroscientists to ponder, but I must admit the fact that post-meditation urine containers more traces of serotonin is going to be very much on my mind the next time the urge to pee strikes during meditation. In terms of evaluation the meditation-epilepsy hypothesis, though, the most compelling new evidence was a reference to an 1993 study suggesting that people who meditate experience symptoms also linked with epilepsy, from phantom vibrations and mild auditory hallucinations to what we might otherwise just call are a more religious experience or spiritual awareness of the world. While this study is old (that is, old in the science of the brain and the new boom of contemplative science), it is also in line with more recent research showing visual hallucinations arising from meditation.
Based on this pair of articles, it seems entirely plausible to think that reducing the usual external stimulation by focusing only on one object might let those seizure-prone neurons get all fired up. Certainly, the evidence is reasonable enough that it shouldn’t be dismissed out of hand, and the potential mechanisms mentioned are specific enough to allow for several possible studies to test the theory more deliberately.
And then….nothing. Or at least, very little. Any link between meditation and epilepsy seems to have fallen off the radar, whether it is as a risk or a treatment. Jaseja has produced one more brief theoretical piece arguing that any claims that meditation helps epilepsy should be evaluated carefully as potential placebo effects stemming from the patients’ expectations of a stress-reducing practice, but no one else seems to have anything to say on the issue. The closest I could find was one study testing whether yoga (which shares some features with meditation, but is also unique) could help treat epilepsy, but otherwise all interest in meditation-related practices and epilepsy seems to have vanished as of 2006. It could be that the population needed for any studies (people who have seizures) is too small, it could be that directly testing something that might trigger a seizure doesn’t pass ethical muster, it could be that there are other steps that need to be taken before investigating alpha waves and serotonin byproducts more thoroughly. I would hate to think that it’s just not fundable or publishable to suggest that meditation could be a harm, not just a help, for some populations.
Jaseja H (2005). Meditation may predispose to epilepsy: An insight into the alteration in brain environment induced by meditation. Medical Hypotheses, 64 (3), 464-467. PMID: 15617849
Jaseja H (2006). Meditation potentially capable of increasing susceptibility to epilepsy – A follow-up hypothesis. Medical Hypotheses, 66 (5), 925-928. PMID: 16434149