Condition usu. seen in patients with dense hemiplegia of left side who deny contiguity of that side; occurs in some patients with brain damage who are unaware of their mental (esp. abstraction) or physical impairment. Cause is lesion in superior parietal cerebral cortex. If lesion extends into adjacent frontal, temporal, or occipital lobes, syndrome may be associated with hallucinations, blunted affect, or abnormal space perception.