Welcome to Strange Cases, a new, occasional series from Science of Us in which we unearth some of medical literature’s most bizarre case reports. Today, we’ll take a look at the case of an elderly woman whose left hand suddenly didn’t seem to belong to her. The hand started hitting her, even tried to choke her, and she was unable to control it. The report appears in a 1998 edition of the Journal of Neurology, Neurosurgery & Psychiatry.
The patient: An 81-year-old woman with an otherwise “unremarkable” medical history.
The problem: The woman was initially admitted to a hospital because she was disoriented, confusing her daughter for a nurse. On the second day of her hospital stay, it was as if her left arm developed a mind of its own: According to the report, “she complained that her left hand was acting as if under someone else’s control; it hit her face and head and she reported that she was afraid of it.”
At this point, she was transferred to Massachusetts General Hospital and the care of neurologist Dr. Hakan Ay, who would be the lead author of this case report. Ay reports that the woman’s left hand seemed to be acting of its own accord:
She held her left hand with the right, claiming to keep “him” from hitting her. When asked what trouble brought her to the hospital, she said that her “left hand tried to strangle her”. She repeated that “someone” was hitting and choking her neck, face, and shoulder. She asked the nurse to restrain her left hand, fearful that “hitting of the breast will cause cancer”. These intermittent movements had an irregular speed with slow and smooth onset but became more jerky and rapid before hitting her body.
In addition to the strange and uncontrollable hand movements, she showed “severe primary sensory loss on the left side,” the case report authors write. For example, when they showed her an ad depicting two kids in a car, “she saw only the rightward child.”
The diagnosis: Ay and the medical team at Massachusetts General observed that the woman showed signs of damage to her right occipital lobe, the region of the brain responsible for interpreting visual information from the left. The case report doesn’t explicitly say what caused the damage, but the authors say that in some patients with similar symptoms, the cause is a stroke.
They diagnosed the woman with alien hand syndrome, which they define in their subsequent paper as the “unwilled, uncontrollable, but seemingly purposeful movements of an upper limb.” After a little more than a week in the hospital, the symptoms subsided; she regained the ability to see objects on her left, and to control the movements of her left arm and hand. Again, the authors do not explicitly say what appeared to have caused the symptoms to stop, but they report a decrease of glucose absorption in the areas of the brain that appeared to be damaged. (I’ve emailed a few neurologists to explain why that might have resulted in her apparent return to normal and will update the post if I hear back.)
It’s lucky for this patient that her symptoms subsided on her own; that sometimes happens to people with alien hand syndrome, and sometimes it doesn’t. There is no treatment, so people with this strange syndrome must use some equally strange ways to control their suddenly uncontrollable hand, like the man who enclosed his alien hand in an oven mitt to keep it from nudging him awake at night.