Invisible doppelgänger and body image disorders in right superior parietal lobule stroke, a case series

Autoscopic phenomena or an "invisible doppelgänger" refer to the illusory reduplication of one's own body. Body image disorder involves distorted perception or decreased body awareness. In the literature, feeling of presence (FOP) is rarely presented with a circumscribed cerebral pathology due to acute vascular lesions, and concomitant FOP and disorders of the body image or the body schema (BIBS) have rarely been reported. We present three cases of both FOP and BIBS disorders. All patients reported the two types of symptoms almost simultaneously: The first patient had the symptom of somatoparaphrenia characterized by deny ownership of the hand and feeling that it does not belong to her, the second patient had the sign of fading limb presented with misuse of his left hand when it was not under visual control and could not mentally represent and locate this part of the body in space, and the third patient had autotopagnosia; he was unable to localize any touched area below the elbow and knee. All patients had right parietal ischemic lesions involving the superior parietal lobule, and two patients had an adjacent additional precuneal involvement. Based on the cases presented here, it is plausible that BIBS may develop in addition to FOP, especially in lesions involving the superior parietal lobule and precuneus.