Writing Abilities in Primary Progressive Aphasia: A Scoping Literature Review.

Area of Science:

• Neurolinguistics
• Clinical Linguistics
• Speech-Language Pathology

Background:

• Writing and typing are central to modern communication.
• Integrating writing assessments into clinical practice is essential for diagnosing and managing primary progressive aphasia (PPA).

Purpose of the Study:

• To systematically review and summarize existing evidence on writing abilities in individuals with PPA.
• To examine writing task types, their limitations, stimulus features, and the impact of language differences.

Main Methods:

• A comprehensive literature search was performed using Google Scholar and PubMed.
• Included studies were peer-reviewed, published in English, and reported quantitative writing task data from at least one PPA subject.
• Fifty-one studies were analyzed, comprising 47 behavioral and 4 neuroimaging studies.

Main Results:

• The literature on PPA writing is fragmented, with significant variability in task design and psycholinguistic control.
• Writing to dictation is common but insufficient; tasks assessing lexico-semantic, morpho-syntactic, and discourse abilities are underutilized.
• Syndromic variations show distinct writing profiles: svPPA (surface dysgraphia), nfvPPA (phonological dysgraphia, agrammatic writing), and lvPPA (mixed errors). Neuroimaging results are heterogeneous.

Conclusions:

• There is a critical need for systematic, linguistically informed writing assessment approaches in PPA.
• Standardized methods will enhance diagnostic precision and enable better cross-linguistic comparability in PPA research.