title: Thalamic alexia with agraphia.
abstract: Alexia with agraphia is defined as an acquired impairment affecting reading and writing ability. It can be associated with aphasia, but can also occur as an isolated entity. This impairment has classically been associated with a left angular gyrus lesion In the present study, we describe a case involving a patient who developed alexia with agraphia and other cognitive deficits after a thalamic hemorrhage. In addition, we discuss potential mechanisms of this cortical dysfunction syndrome caused by subcortical injury. We examined a patient who presented with alexia with agraphia and other cognitive deficits due to a hemorrhage in the left thalamus. Neuropsychological evaluation showed attention, executive function, arithmetic and memory impairments. In addition, language tests revealed severe alexia with agraphia in the absence of aphasia. Imaging studies disclosed an old thalamic hemorrhage involving the anterior, dorsomedial and pulvinar nuclei. Tractography revealed asymmetric thalamocortical radiations in the parietal region (left <right), and single photon emission computed tomography demonstrated hypoperfusion in the left thalamus that extended to the frontal and parietal cortices. Cortical cognitive deficits, including alexia with agraphia, may occur as the result of thalamic lesions. The probable mechanism is a diaschisis phenomenon involving thalamic tract disconnections.
authors.affiliation: Behavioral and Cognitive Neurology Unit, Department of Neurology and Cognitive Disorders Reference Center (CEREDIC);
authors.forename: Fábio Henrique
authors.initials: FH
authors.lastname: de Gobbi Porto
authors.forename: Maria Isabel
authors.initials: MI
authors.lastname: d'Ávila Freitas
authors.forename: Maira Okada
authors.initials: MO
authors.lastname: de Oliveira
authors.forename: Leandro Tavares
authors.initials: LT
authors.lastname: Lucato
authors.forename: Marco
authors.initials: M
authors.lastname: Orsini
authors.forename: Sara Lúcia Silveira
authors.initials: SL
authors.lastname: de Menezes
authors.forename: Regina Miksian
authors.initials: RM
authors.lastname: Magaldi
authors.forename: Cláudia Sellitto
authors.initials: CS
authors.lastname: Porto
authors.forename: Sonia Maria
authors.initials: SM
authors.lastname: Dozzi Brucki
authors.forename: Ricardo
authors.initials: R
authors.lastname: Nitrini