Premium
Primary progressive aphasia: PPA and the language network
Author(s) -
Sonty Sreepadma P.,
Mesulam M.Marsel,
Thompson Cynthia K.,
Johnson Nancy A.,
Weintraub Sandra,
Parrish Todd B.,
Gitelman Darren R.
Publication year - 2003
Publication title -
annals of neurology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.764
H-Index - 296
eISSN - 1531-8249
pISSN - 0364-5134
DOI - 10.1002/ana.10390
Subject(s) - primary progressive aphasia , functional magnetic resonance imaging , aphasia , precentral gyrus , fusiform gyrus , psychology , audiology , superior temporal gyrus , cognition , neuroscience , cognitive psychology , dementia , magnetic resonance imaging , medicine , pathology , disease , frontotemporal dementia , radiology
Primary Progressive Aphasia (PPA) is a behaviorally focal dementia syndrome with deterioration of language functions but relative preservation of other cognitive domains for at least the first two years of disease. In this study, PPA patients with impaired word finding but intact comprehension of conversational speech and their matched control subjects were examined using voxel‐based morphometry (VBM) and functional magnetic resonance imaging (fMRI). fMRI compared signal changes during phonological and semantic language tasks with those during a control task (matching letters). PPA patients showed longer reaction times and reduced accuracy versus controls on the language tasks, but no performance differences on the control task. VBM demonstrated reduced gray matter in left superior temporal and inferior parietal regions in the PPA group. However, these patients showed a normal pattern of activation within the classical language regions. In addition, PPA patients showed activations, not seen in normals, in fusiform gyrus, precentral gyrus, and intra‐parietal sulcus. These activations were found to correlate negatively with measures of naming and task performance. The additional activations in PPA may therefore represent a compensatory spread of language‐related neural activity or a failure to suppress activity in areas normally inhibited during language tasks. Ann Neurol 2003;53:000–000