A 2003 study in Epilepsy and Behavior has some descriptions of the ecstatic seizures experienced by some patients with epilepsy.
They include intense erotic and spiritual experiences, feelings of become close to and blending with other people, and some sensations that couldn't be fully captured in words.
I've put some of the descriptions below because they sound absolutely wonderful:
The first seizure occurred during a concert when he was a teenager. He remembers perceiving short moments of an indefinable feeling. Such episodes recurred and a few months later evolved into a GTC [generalized tonic–clonic seizure]. He characterizes these sensations as ‘a trance of pleasure.’ ‘It is like an emotional wave striking me again and again. I feel compelled to obey a sort of phenomenon. These sensations are outside the spectrum of what I ever have experienced outside a seizure.’ He also describes cold shivering, increased muscle tension, and a delicious taste, and he swallows repeatedly. He enjoys the sensations and is absorbed in them in a way that he can barely hear when spoken to. When in a particular, relaxed mood, he can sometimes induce seizures by ‘opening up mentally’ and contracting muscles. He denies any religious aspects of the symptoms. ‘It’s the phenomenon, the feeling, the fit taking control.’ It lasts a few minutes and afterward he is tired with difficulties expressing himself for about 1 hour.
This man has a multifaceted symptomatology and a tendency to interpret bodily sensations as supernatural phenomena. Nevertheless, from the beginning of his forties, he experienced distinct, stereotypical attacks with a ‘change of concept of the surrounding world.’ He reports an ‘oscillating erotic sensation, like twinkling polar light’ in his pelvic region and down the inside of his thighs. This is described as different from sexual excitement, more like ‘an erogenous charge of the skin.’ He may also have a clairvoyant feeling of a ‘telepathic contact with a divine power.’ These sensations are of short duration and may be accompanied by faintness and followed by drowsiness. With carbamazepine treatment, the frequency of these attacks has been considerably reduced.
The attacks started in his first school year. The experiences are beyond what can be described in words. ‘I can sense the colours red and orange without seeing them. The feeling has an erotic aspect. It starts in the stomach and spreads upwards. It is pleasant, but not similar to ordinary joy. It is like an explosion.’ In the close presence of another person, he can feel a sort of peculiar unification. An intense déjà vu sensation, a queer taste, and ‘gooseflesh’ are also components of the seizures. As a child he was surprised that his friends denied having similar feelings, and he learned to keep them to himself. Sometimes these attacks evolved into CPSs with reduced consciousness and complex automatisms and afterward he had transient difficulties speaking. Before the diagnosis of epilepsy was made in his late teens, he was referred to a psychiatrist. A right-sided temporal lobe calcification was diagnosed by computed tomography at about 30 years, but he refused surgery. At 42, an expansion in the same region was found by MRI, and he was operated for an anaplastic oligodendroglioma. He was seizure-free for 6 years until recurrence of the tumor.
One of the striking things about epilepsy is how different each person's experience of having a seizure can be.
While it is stereotypically assumed to be a negative experience, some aspects can be remarkably beautiful.
The Russian author Dostoyevsky famously said of his epilepsy 'I would experience such joy as would be inconceivable in ordinary life - such joy that no one else could have any notion of. 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 ten or more years of my life, even my whole life perhaps.'
There are several more case descriptions in the article, all of which have some aspect which touch at least the edge of ecstasy, if not the very heart of the experience.
(Via Mind Hacks.)