As some people with epilepsy discover, the condition can have a bright side. The Russian writer Fyodor Dostoevsky once told a friend that, in the first moments of his seizures, “I would experience such joy as would be inconceivable in ordinary life … I would feel the most complete harmony in myself and in the whole world and this feeling was so strong and sweet that for a few seconds of such bliss I would give 10 or more years of my life, even my whole life perhaps.”
This “ecstatic aura” reflects very localized seizure activity in the brain; it is often followed by more generalized seizure activity and the loss of consciousness. Although reported by only a minority of epileptics, it seems to be unforgettable to those who do experience it. “They know nothing else that has this intensity in their life,” says Fabienne Picard, a neurologist at the University Hospital of Geneva and lead author of a study of five such cases in the November issue of Epilepsy and Behavior.
New data on these experiences, along with a new theory about how the brain experiences things, have prompted Picard and her co-author A.D. Craig, from the Barrow Neurological Institute in Phoenix, Ariz., to question the current thinking about the origin of ecstatic seizures.
Such experiences are typically reported by people who have been diagnosed with “temporal lobe epilepsy,” in which seizure activity originates in one of the brain’s temporal lobes. But most such diagnoses are made on the basis of scalp-mounted electroencephalograph (EEG) recordings, which can’t easily distinguish activity in the temporal lobe from activity in deeper regions nearby.
In Picard’s cases, there were hints that the ecstatic experiences were linked to unusual activity in the insular cortex, or insula, which lies just beneath the temporal lobe. In three of the cases, the epilepsy appeared to have been caused by a tumor that had compressed or was close to the anterior (front) insula among other structures. In one of these cases, Picard was able to obtain brain-imaging data during a seizure with a standard radioactive-tracer-based technique, single-photon emission computed tomography (SPECT). The data showed increased blood flow that reached a peak in the anterior insula on the right side of the brain.
A clue from enhanced self-awareness
The sensations reported by Picard’s patients are also consistent with a hypothesis put forward recently by Craig: The anterior insula may be where all manner of feelings, including bodily pleasures and pains; sights, sounds and smells; emotions, expectations and intentions; and even the sense of one’s physical surroundings are integrated into a unified sense of a “self” moving through time.
If this hypothesis is true, then disturbances to the anterior insula would likely cause disturbances to the usual sense of self-awareness. In fact, Picard’s patients unanimously reported an enhanced self-awareness. The patient in whom an increased insular blood flow was measured described this enhancement as “a stronger consciousness of the body and the mind.”
Antoine Bechara, a neuroscientist at the University of Southern California who has published widely on the insula and its functions, calls the Picard-Craig paper “an absolutely fantastic study,” because it finally ties ecstatic epileptic experiences to a brain region whose functions could plausibly account for them. “There is nothing about the temporal lobes that suggests that they have anything to do with feelings,” he says, whereas there are now converging lines of evidence that point to the anterior insula as a structure that mediates both good and bad feelings.
Bechara and his colleagues published a study in 2007 showing that some smokers who sustained insula damage, for example if they had a stroke, suddenly lost their craving for cigarettes and were able to quit smoking relatively easily. That has made the insula a focus among addiction researchers, some of whom hope that addiction behavior can be changed by therapeutically modifying insula activity.
Understanding ecstatic seizure experiences may help in this regard, since these experiences are often described as life-altering—which suggests that the functioning of the responsible brain region has itself been permanently altered. One patient told Picard that as a result of her ecstatic seizures, “I see the world differently, every sensation is stronger; for instance I see more colors than before, and I have more detailed perceptions, particularly when listening to music.”
Too deep to study easily
Proving the origin of these experiences won’t be easy. Although SPECT imaging can sometimes be performed during a seizure, its resolution is too low to enable identification of the precise brain area responsible. Functional magnetic resonance imaging (fMRI) offers greater spatial resolution, but hasn’t been considered useful in cases where seizures are rare and unpredictable. Neurologists also have to contend with the fact that seizure activity can change, and can trigger secondary activity in the brain, much more rapidly than neuroimaging techniques such as SPECT and fMRI can measure.
The ideal, Picard says, would be to insert EEG electrodes in and around the insulas of ecstatic seizure patients while they remain under observation in the hospital. Then as seizures occur, their origins and spreadings would be tracked precisely. Though very hazardous, such studies are often justified to evaluate patients for brain surgery, when their epilepsy is debilitating and other treatments have failed.
Patients who fit that description are too rare, Picard says, to permit her to do such a study now. But she expects to do more modest experiments in the near term, possibly looking for insula-related cognitive or emotional abnormalities in her ecstatic seizure patients, and applying fMRI to other patients who report ecstatic experiences during more controllable forms of epilepsy. With incremental steps like these, she hopes eventually to zero in on the mysterious source of epileptic bliss.