She's Cured!

An elderly woman presented with acute onset of alteration of consciousness, expressive aphasia and short-lived right sided weakness. Her symptoms came on abruptly, twice in the last three weeks. The first time she was diagnosed with a stroke and effectively rehabilitated, until she had the second spell. Her EEG contains left temporal slowing and spikes suspicious for an epileptogenic focus. Her MRI reveals an abnormal area in the left posterior temporal and adjoining parietal lobe. At this time it is unclear what the lesion exactly is. An MR Spectroscopy will be performed to differentiate between an infarct or a neoplasm.

A curious element of the patient's presentation is that she no longer has the arthritic pain that plagued her for years. A condition called pain asymbolia offers a possible explanation. Pain asymbolia describes the situation in which a patient perceives a painful stimulus but is unconcerned by it and may even laugh. There is a disconnect between the perception of pain and the affective component of pain. Ramachandran hypothesizes an explanation for this phenomenon. Following integration of spinothalamic pain information in the insular cortex, there are connections with the amygdala (and from there to the limbic system) that may be disrupted, thus producing pain asymbolia. According to Ramachandran, laughter may result from the disconnect between the pain and its lack of emotional content, an organic punch-line.

However in this patient, not only is the affective component of pain absent, she has no pain at all.

Painful stimuli are modified by modulatory pathways, some of them arising in the somatosensory cortex (others arising from the hypothalamus, periaqueductal gray matter of the midbrain, the raphe nuclei, and other nuclei of the rostral ventral medulla). Perhaps a seizure can cause overactivation in one of these modulatory pathways, in this case the somatosensory cortex or one of its association areas, effectively quelling pain stimuli at the level of the spinal cord.

Ramachandran VS. A Brief Tour of Human Consciousness: From Impostor Poodles to Purple Numbers. Pi Press, New York, 2004.