A case of pre- and postcentral, insular cortex, and frontal, parietal opercular injuries in which the activeness at the time of paralytic limb contact affected the reduction of numbness sensation

Abstract

We report a 61-year-old ambidextrous woman with severe numbness in the right upper and lower limbs, caused by cardiogenic brain embolism. MRI revealed acute brain infarcts in the precentral gyrus, postcentral gyrus, posterior part of the frontal-operculum, parietal operculum, and posterior part of the insula. She showed severe motor paralysis, mild sensory disturbance including hypoesthesia of superficial and deep sensations, combined sensation disturbance, and numbness of the right upper and lower limbs. The patient described the numbness as shooting pain, which was considered to be allodynia associated with pseudo-thalamic pain. As a feature of the sensory disturbance, numbness was absent when she touched her body by herself, but it was present when the examiner touched her, or when her body contacted bedding or a desk. We suggest the following mechanism of numbness in the patient: as sensory prediction can lead to sensory elimination on active personal contact, numbness was eliminated when she touched herself. On the other hand, as sensory prediction is rarely caused by physical contact with another person, numbness was induced by such contact with the examiner.