title: Primary face motor area as the motor representation of articulation.
abstract: No clinical data have yet been presented to show that a lesion localized to the primary motor area (M1) can cause severe transient impairment of articulation, although a motor representation for articulation has been suggested to exist within M1. Here we describe three cases of patients who developed severe dysarthria, temporarily mimicking speech arrest or aphemia, due to a localized brain lesion near the left face representation of the human primary motor cortex (face-M1). Speech was slow, effortful, lacking normal prosody, and more affected than expected from the degree of facial or tongue palsy. There was a mild deficit in tongue movements in the sagittal plane that impaired palatolingual contact and rapid tongue movements. The speech disturbance was limited to verbal output, without aphasia or orofacial apraxia. Overlay of magnetic resonance images revealed a localized cortical region near face-M1, which displayed high intensity on diffusion weighted images, while the main portion of the corticobulbar fibers arising from the lower third of the motor cortex was preserved. The cases suggest the existence of a localized brain region specialized for articulation near face-M1. Cortico-cortical fibers connecting face-M1 with the lower premotor areas including Broca's area may also be important for articulatory control.
authors: Department of Neurology, Division of Neuroscience, Graduate School of Medicine University of Tokyo, 7-3-1 Hongo Bunkyo-ku1, 13-8655 Tokyo, Japan. yterao-tky@umin.ac.jp
authors: Yasuo
authors: Y
authors: Terao
authors: Yoshikazu
authors: Y
authors: Ugawa
authors: Tomotaka
authors: T
authors: Yamamoto
authors: Yasuhisa
authors: Y
authors: Sakurai
authors: Tomohiko
authors: T
authors: Masumoto
authors: Osamu
authors: O
authors: Abe
authors: Yoshitaka
authors: Y
authors: Masutani
authors: Shigeki
authors: S
authors: Aoki
authors: Shoji
authors: S
authors: Tsuji
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001184:Articulation Disorders / Q000209:etiology* / Q000473:pathology; D001930:Brain Injuries / Q000150:complications* / Q000473:pathology; D001931:Brain Mapping / Q000379:methods; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005145:Face; D005260:Female; D006801:Humans; D008297:Male; D009044:Motor Cortex / Q000473:pathology* / Q000503:physiopathology*