Monday, 13 June 2005

The woman in the mirror

Imagine if wherever you looked, you saw a translucent mirror image of yourself, about one metre in front of you. It’s wearing the same clothes as you and if you wave your right hand, it waves back in identical fashion (but with its left hand, just like a mirror image). That’s what patient B.F. reported seeing three months after she was brain damaged during the still birth of her baby, when she experienced seizures and fell into a brief coma.

Autoscopy as it’s known, is different from an out-of-body experience in which people report looking down onto their ‘real’ body below. And it’s different from something called ‘heautoscopy’ in which people believe they have an exact double, which may or may not be visible. B.F. knew the mirror image she could see was unreal.

B.F.’s brain damage left her unable to read or recognise familiar objects, but her sight was okay. When Giovanna Zamboni and her colleagues placed their hand on B.F.’s shoulder, she reported seeing a hand-like object appear on the illusory mirror image before her. When researchers drew a circle on her forehead in pencil, she reported seeing something dark and round tattooed on the forehead of her mirror image. If the researchers placed a sheet of paper where she said the image was located, then she said the image still appeared, but closer to her, on the surface of the paper. B.F. said the strange image she saw was clearer the more attention she paid to it. Six months after her trauma, B.F. said the image had gone, having gradually disappeared over the weeks.

The researchers believe B.F.’s strange experience was caused by damage to the part of her brain, the occipital cortex, that is normally responsible for early, basic visual processing. “…(undamaged) higher-order cortical visual areas, deprived of their input, may have established ‘abnormal cross-talk’ with cortical areas involved in body-schema representation”, the researchers explained.

“… autoscopy is a visual interpretation of the representation of the self, in which self-sensory or proprioceptive information is transformed into a visual image”, they said.
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Zamboni, G., Budresi, C., Nichelli, P. (2005). “Seeing oneself”: a case of autoscopy. Neurocase, 11, 212-215.

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

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