Scene from Paranormal ActivityAfter a young, middle class couple moves into what seems like a typical suburban “starter” tract house, they become increasingly disturbed by a presence that may or may not be demonic but is certainly most active in the middle of the night.Especially when they sleep. Or try to.A new case study in Cortex by neurologist Dr. Fabienne Picard (2010) reports on a patient who experienced unusual phenomena during epileptic seizures. She had the convincing sense that several familiar people (family members) were standing before her. This experience of a "sensed presence" is a classic trope in movies with supernatural themes (e.g., Carnival of Souls [available at Internet Archive], The Haunting [trailer for the 1963 version], Poltergeist, Dark Water), but it's generally attributed to ghosts and not to seizure activity.
Here's the case report:
A 62-year-old right-handed woman of normal psychiatric history presented a simple focal epileptic seizure including a complex sensation characterized by feeling the presence of several members of her family in the immediate environment, associated with paresthesia of the right hemibody (excluding the face). The feeling of presences and the paresthesia (numbness) appeared concomitantly and lasted in total several minutes. The episode occurred while she was sitting alone on the sofa of her living room and immediately felt the presence of four persons in her frontal space. She did not see or hear these persons (no visual or auditory hallucinations), but felt vividly their presence in her peripersonal [within reach] and near extrapersonal space [just outside of reach]. She “recognized” them as close family members. Closest was her grand-daughter who was sitting on the floor immediately in front of her, without any left or right lateralization in relation to her body, whereas the three other persons, her daughter and two other grand-children, were experienced to be localized at a distance of several meters. ... This highly vivid and convincing feeling of presences was described by the patient as deeply pleasant, although she guessed that it was not possible that they were really there, as she was alone just before. ... She was treated with pregabalin (300 mg/day) and there was no recurrence of simple or complex partial seizures and no further feeling of presences.MRIs revealed abnormal findings due to a right hemisphere subcortical stroke 10 months before the episode (Fig. 1A). The patient's stroke affected a portion of the basal ganglia (the putamen and the globus pallidus) and a large white matter tract within (the internal capsule). Left hemisphere findings in the insular cortex were also apparent, and this was the likely seizure focus. Strokes are known to increase the incidence of seizures: in one study 8.6% of those with ischemic stroke [occlusion of blood supply] and 10.6% of those with hemorrhagic stroke [bleed] had one or more seizures within a year (Bladin et al., 2000).
Fig. 1 (adapted from Picard, 2010). FLAIR coronal MR images of the patient. (A) two days after a right capsulo-lenticular haemorragic stroke. (B) ten months later, at the time of the episode of feeling of presence. In addition to the right capsulo-lenticular sequela extending to the insula, a hypersignal is visible in the white matter/grey matter border of the left insular region [already visible in (A)], as well as a diffuse corticosubcortical atrophy, predominating in the right hemisphere, and a leukoencephalopathy [white matter disease].
Picard (2010) thinks this particular case is unique and not a more typical disorder of body perception:
Most authors consider the feeling of a presence (FP) as a disorder of own body perception, an illusory reduplicative phenomena involving the self. Thus FP would be akin to the three main forms of autoscopic phenomena (seeing a double of oneself) which include a) out-of-body experience. The subjects appear to see themselves and the world from a location above their physical body. The self is localized outside one's physical body (disembodiment); b) autoscopic hallucination, which consists of seeing one's body in extracorporeal space (as a double) without disembodiment; and c) heautoscopy, an intermediate form between out-of-body experience and autoscopic hallucination.Instead, the felt presence was more akin to a "hallucination" for known people going about normal daily activities. Nonetheless, involvement of the insula, important for interoceptive awareness of bodily states (Craig, 2009), is still suggestive of a disruption in the sense of self and its interaction with the external world.
To end our story, the patient's experience of a sensed presence did not recur once her seizures were controlled with medication. A short neurological horror film resolved by prescription of an anticonvulsant drug might not be a strong sell in Hollywood.
References
Bladin CF, Alexandrov AV, Bellavance A, Bornstein N, Chambers B, Coté R, Lebrun L, Pirisi A, Norris JW. (2000). Seizures after stroke: a prospective multicenter study. Arch Neurol. 57:1617-22.
Craig AD. How do you feel--now? The anterior insula and human awareness. (2009). Nat Rev Neurosci. 10:59-70.
Picard, F. (2010). Epileptic feeling of multiple presences in the frontal space. Cortex DOI: 10.1016/j.cortex.2010.02.002
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