title: Effects of mental rotation on acalculia: differences in the direction of mental rotation account for the differing characteristics of acalculia induced by right and left hemispheric brain injury.
abstract: We observed a 59-year-old right-handed man with an infarction in his right-middle cerebral artery that included the parietal lobe, who abnormally manipulated mental images in the horizontal direction, resulting in calculation disturbances. Three years later, the patient suffered an infarction in the left parietal lobe and displayed abnormalities during the creation of mental images; i.e., he rotated them in the vertical direction, which again resulted in calculation disturbances. These mental imagery disturbances might indicate that a common acalculia mechanism exists between the right and left hemispheres.
authors: a Department of Brain Functional Imaging , Human Brain Research Center, Kyoto University, Graduate School of Medicine , Kyoto , Japan.
authors: Tomohiko
authors: T
authors: Asada
authors: Yoshihiro
authors: Y
authors: Takayama
authors: Jiro
authors: J
authors: Oita
authors: Hidenao
authors: H
authors: Fukuyama
mesh_terms: D001921:Brain / Q000473:pathology; D060705:Dyscalculia / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D007092:Imagination / Q000502:physiology*; D020244:Infarction, Middle Cerebral Artery / Q000150:complications*; D008297:Male; D008875:Middle Aged; D010296:Parietal Lobe / Q000473:pathology; D013028:Space Perception / Q000502:physiology*