Progressive nonfluent aphasia and its characteristic motor speech deficits

Jennifer M. Ogar, Nina Dronkers, Simona M. Brambati, Bruce L. Miller, Maria Luisa Gorno-Tempini

Research output: Contribution to journalArticle

97 Scopus citations

Abstract

Progressive nonfluent aphasia (PNFA) is a clinical syndrome characterized by motor speech impairment and agrammatism, with relative sparing of single word comprehension and semantic memory. PNFA has been associated with the characteristic pattern of left anterior insular and posterior frontal atrophy, including the motor and premotor regions and Broca's area. Postmortem histopathologic evidence has shown that PNFA is usually associated with tau pathology, although focal Alzheimer disease pathology and tau-negative, ubiquitin-TDP-43 inclusions also have been reported in association with this clinical syndrome. We performed a detailed analysis of motor speech errors in 18 patients with PNFA and investigated their neural correlates using voxel-based morphometry on magnetic resonance imaging scans. Seven patients demonstrated only apraxia of speech (AOS) errors, whereas 11 showed AOS along with dysarthria. Slow rate of speech, effortful articulation with groping, and consonant distortions were the most common AOS errors. Hypernasality was the most represented dysarthric feature and dysarthria was most often classified as spastic, hypokinetic, or mixed spastic-hypokinetic. Neuroimaging results demonstrated that patients with AOS-only and AOS plus dysarthria showed atrophy in the left posterior frontal, anterior insular, and basal ganglia regions when compared with controls. Patients with AOS plus dysarthria showed greater damage than patients with AOS-only in the left face portion of primary motor cortex and left caudate. PNFA is a distinct frontotemporal lobar degeneration clinical syndrome associated with characteristic clinical, neuroimaging, and pathologic features. The clinical features are driven by the severity of left frontal and caudate damage.

Original languageEnglish (US)
JournalAlzheimer Disease and Associated Disorders
Volume21
Issue number4
DOIs
StatePublished - Oct 2007
Externally publishedYes

Keywords

  • Apraxia of speech
  • Dysarthria
  • FTLD
  • Progressive aphasia
  • Progressive nonfluent aphasia
  • VBM

ASJC Scopus subject areas

  • Geriatrics and Gerontology
  • Psychiatry and Mental health
  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Progressive nonfluent aphasia and its characteristic motor speech deficits'. Together they form a unique fingerprint.

  • Cite this