Reading words and other people: A comparison of exception word, familiar face and affect processing in the left and right temporal variants of primary progressive aphasia

• Published in: Cortex Vol. 82; pp. 147 - 163
• Main Authors: Binney, Richard J., Henry, Maya L., Babiak, Miranda, Pressman, Peter S., Santos-Santos, Miguel A., Narvid, Jared, Mandelli, Maria Luisa, Strain, Paul J., Miller, Bruce L., Rankin, Katherine P., Rosen, Howard J., Gorno-Tempini, Maria Luisa
• Format: Journal Article
• Language: English
• Published: Italy Elsevier Ltd 01.09.2016
• Subjects: Aged; Anterior temporal lobe; Aphasia, Primary Progressive - diagnostic imaging; Aphasia, Primary Progressive - pathology; Aphasia, Primary Progressive - psychology; Facial Recognition - physiology; Female; Humans; Language; Magnetic Resonance Imaging; Male; Middle Aged; Neuropsychological Tests; Pattern Recognition, Visual - physiology; Primary progressive aphasia; Reading; Recognition (Psychology) - physiology; Semantic dementia; Social cognition; Social Perception; Surface dyslexia; Temporal Lobe - diagnostic imaging; Temporal Lobe - pathology; Semantic dementia; Primary progressive aphasia; Surface dyslexia; Anterior temporal lobe; Social cognition
• ISSN: 0010-9452; 1973-8102; 1973-8102
• DOI: 10.1016/j.cortex.2016.05.014

Semantic variant primary progressive aphasia (svPPA) typically presents with left-hemisphere predominant rostral temporal lobe (rTL) atrophy and the most significant complaints within the language domain. Less frequently, patients present with right-hemisphere predominant temporal atrophy coupled with marked impairments in processing of famous faces and emotions. Few studies have objectively compared these patient groups in both domains and therefore it is unclear to what extent the syndromes overlap. Clinically diagnosed svPPA patients were characterized as left- (n = 21) or right-predominant (n = 12) using imaging and compared along with 14 healthy controls. Regarding language, our primary focus was upon two hallmark features of svPPA; confrontation naming and surface dyslexia. Both groups exhibited naming deficits and surface dyslexia although the impairments were more severe in the left-predominant group. Familiarity judgments on famous faces and affect processing were more profoundly impaired in the right-predominant group. Our findings suggest that the two syndromes overlap significantly but that early cases at the tail ends of the continuum constitute a challenge for current clinical criteria. Correlational neuroimaging analyses implicated a mid portion of the left lateral temporal lobe in exception word reading impairments in line with proposals that this region is an interface between phonology and semantic knowledge.