The Heterogeneity of Reading and Spelling Deficits in Posterior Cortical Atrophy

Posterior Cortical Atrophy (PCA) is a clinical syndrome marked by progressive visuospatial impairment, usually due to underlying Alzheimer's disease. While reading and spelling deficits are recognized clinical features of this syndrome, the contributions of visuoperceptual versus linguistic deficits to these impairments are still unclear.

To that end, we examined reading and spelling performance in 23 individuals from the Massachusetts General Hospital PCA cohort. Participants completed tests of reading from the Western Aphasia Battery and spelling to dictation from the Boston Diagnostic Aphasia Examination. A mixed-methods analysis included quantitative scoring and qualitative observations of visual behaviors, error patterns, and compensatory strategies.

Participants commonly demonstrated visual scanning errors, difficulty following multi-line text, and spelling errors reflecting both visual-perceptual and orthographic-linguistic breakdowns.

Because reading and spelling in PCA are variably impaired cognitive skills driven by visual deficits and lexical vulnerability, assessments and interventions must account for deficits in both cognitive processes. Our findings highlight the vulnerability of reading and spelling in PCA and underscore the need for multimodal assessment strategies that account for the interplay of visual, phonological, and lexical processes. These insights can inform diagnosis and guide the development of accessible interventions tailored to optimize compensatory strategies to support functional language abilities.