title: Neural substrates of the 'low-level' system for speech articulation: Evidence from primary opercular syndrome.
abstract: We describe a patient with progressive disorder of speech, without language impairment (opercular syndrome). Morphometric analysis confirmed asymmetric volume reduction of the precentral areas (>left). Diffusion imaging showed significant white matter changes in the left frontal lobe, with specific involvement of the left corticobulbar tract and connections between supplementary/pre-supplementary motor areas and the frontal operculum (frontal aslant tract). We suggest that the organization of expressive language includes a 'low level' motor system principally distributed in the left hemisphere that shows specific susceptibility to neurodegeneration, distinct from neural systems subtending praxic, and cognitive aspects of language.
authors: Department of Psychology, Catholic University, Milan, Italy.
authors: Maria Caterina
authors: MC
authors: Silveri
authors: Centre for Medicine of Ageing, Catholic University, Rome, Italy.
authors: Francesco
authors: F
authors: Incordino
authors: Centre for Medicine of Ageing, Catholic University, Rome, Italy.
authors: Rita
authors: R
authors: Lo Monaco
authors: Institute of Neurology, Catholic University, Rome, Italy.
authors: Alessandra
authors: A
authors: Bizzarro
authors: Institute of Neurology, Catholic University, Rome, Italy.
authors: Carlo
authors: C
authors: Masullo
authors: IRCSS Neurological Center "Bonino-Pulejo", Messina, Italy.
authors: Francesca
authors: F
authors: Piludu
authors: Department of Neuroimaging, Catholic University, Rome, Italy.
authors: Cesare
authors: C
authors: Colosimo
mesh_terms: D000368:Aged; D003680:Deglutition Disorders / Q000473:pathology* / Q000503:physiopathology*; D004401:Dysarthria / Q000473:pathology* / Q000503:physiopathology*; D005158:Facial Paralysis / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology; D006801:Humans; D009044:Motor Cortex / Q000473:pathology; D009434:Neural Pathways / Q000000981:diagnostic imaging* / Q000473:pathology*; D011712:Pyramidal Tracts / Q000473:pathology; D013060:Speech; D066127:White Matter / Q000473:pathology
keywords: aslant tract; opercular syndrome; phonological short-term memory; primary anarthria