Somatoparaphrenia. Where did the true limb finish?

SomatoparaphreniaSomatoparaphrenia of the left body limbs, due to unilateral right hemisphere lesion, is the delusion that one’s own limb belongs to someone else. This condition inexorably disrupts the sense of ownership of his own limb and body. The patient feels this limb belonging to his/her spouse or to another relative (even a dead one) or, more rarely, to a perfect stranger. This limb generally menaces the patient or it has some properties that are antithetic to him. The exact pathogenic mechanism of this condition remains speculative, but somatoparaphrenia shares similar mechanisms with other syndromes due do right hemisphere damage (somatoagnosia, anosognosia, spatial neglect, misoplegia and so on.)
This loss of the sense of uniqueness might be the result of some aberrant sensory processing coupled with a failure of reality-checking. Hence, somatoparaphrenia reminds to some delusions occurring with schizophrenia or to some experiences occurring in dissociative disorders (including spirit possession), or with hallucinatory drugs or with dreams.
Finally, is the normal feeling of the ownership of his own limb, disrupted or just inhibited by the effect of the lesion on the sensory system and body schema? Hypnosis can induce the phenomenon in healthy persons. The rubber hand illusion can improve somatoparaphrenia in patients with right hemisphere damage. However, who creates in the patient’s mind the semantic concept of a new limb?
What would it happen in patients with right hemisphere damage and somatoparaphrenia by inhibiting homologous areas on the left hemisphere (the devil’s advocate) with transcranial magnetic stimulation. Where did the true limb finish?

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