Tight link between our sense of limb ownership and self-awareness of actions.
OBJECTIVE
Hemiparetic stroke patients with disturbed awareness for their motor weakness (anosognosia for hemiparesis/-plegia [AHP]) may exhibit further abnormal attitudes toward or perceptions of the affected limb(s). The present study investigated the clinical relationship and the anatomy of such abnormal attitudes and AHP.


METHODS
In a new series of 79 consecutively admitted acute stroke patients with right brain damage and hemiparesis/-plegia, different types of abnormal attitudes toward the hemiparetic/plegic limb (asomatognosia, somatoparaphrenia, anosodiaphoria, misoplegia, personification, kinaesthetic hallucinations, supernumerary phantom limb) were investigated.


RESULTS
Ninty-two percent of the patients with AHP showed additional "disturbed sensation of limb ownership" (DSO) for the paretic/plegic limb. The patients had the feeling that their contralesional limb(s) do not belong to their body or even belong to another person. Analysis of lesion location revealed that the right posterior insula is a crucial structure involved in these phenomena.


CONCLUSIONS
DSO for hemiparetic/-plegic limbs and AHP are tightly linked both clinically and anatomically. The right posterior insula seems to be a crucial structure involved in the genesis of our sense of limb ownership and self-awareness of actions.
Baier
Bernhard
B
Karnath
Hans-Otto
HO
D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D000377:Agnosia; D001828:Body Image; D002540:Cerebral Cortex / Q000503:physiopathology; D005260:Female; D007839:Functional Laterality; D006212:Hallucinations / Q000503:physiopathology / Q000523:psychology; D006429:Hemiplegia / Q000503:physiopathology* / Q000523:psychology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010291:Paresis / Q000503:physiopathology* / Q000523:psychology*; D010465:Perception; D020521:Stroke / Q000503:physiopathology / Q000523:psychology