Simultanagnosia in a patient with right brain lesions

Sirs: Simultanagnosia was originally observed by Balint [1] in a patient with a bilateral parieto-occipital lesion. This symptom was defined by Wolpert [8] as an impairment in the ability to appreciate the overall meaning of a complex picture, despite a preserved ability to perceive the individual elements or details. Wolpert reported simultanagnosia associated with letter-by-letter reading in a patient with a unilateral left parieto-occipital stroke. However, simultanagnosia is observed mainly in bilateral parieto-occipital lesions [4] and has never been reported in patients with strictly right-sided lesions [2, 7]. We report here the case of an 87year-old right-handed woman with 5 years of education who had simultanagnosia due to a right parieto-occipital brain tumor. She was fully independent until September 1997, when she presented with subacute memory loss. When hospitalized in December 1997, neurological examination revealed a left inferior quadranopsia without of any other sensory or motor deficits. She scored 21/30 on the MiniMental State Examination of Folstein, losing two points on temporospatial orientation, five on calculation, one on free recall, and one on reading. Her spontaneous speech was normal. She had a mild anomia in confrontation naming of isolated objects (57/80 on the DO80 naming test [6]); however, she described perfectly the use of the objects that she failed to name. Although the patient did not complain of any visual disturbances, careful examination yielded several abnormalities. A left visuospatial hemineglect was evident in neuropsychological tests on figure cancellation, line bisection, free drawing, and object copying. She was also prosopagnosic and failed in naming and describing nine of ten famous faces. However, when names were orally presented, she knew who the named persons were and could describe their facial features perfectly. Her performance on color naming was normal. When asked to analyze the “Cookie Theft” drawing of the Boston Diagnostic Aphasia Examination, she responded by slowly describing one-by-one only certain elements and being unable to bind them in to a global visual scene. The elements that she did not mention were not related exclusively to the left side of the drawing. She recognized correctly the mother and little boy, who are found on the opposite side of the picture, but was unable to determine their relative location and orientation. Her performance was similar with photographs of complex real scenes. Moreover, she failed to identify all the elements in an overlapping figures test, although she could recognize them when each one was presented independently. In the Navon letters task (where small letters are arranged so as to comprise a larger letter), she could identify the small letters but never the larger ones. Moreover, she showed a size effect on an Arabic digit identification test (where numbers are presented randomly in small or large formats), recognizing the digits correctly only when they were small. She failed to read words and sentences although she was able to recognize single upper-case letters. The simultanagnosia was not associated with any other signs of Balint’s syndrome, such as optic ataxia and gaze apraxia. Cerebral magnetic resonance imaging revealed the presence of two LETTER TO THE EDITORS