Julia Straus, Julian Ockelmann, Elena Bolt, Stefan Elmer, Nathalie Giroud
Adolescents with hearing loss (HL) often display difficulties in written language processing, yet the contribution of morphosyntax remains uncertain. We examined written German morphosyntax in adolescents with HL, most of whom used cochlear implants, relative to monolingual and multilingual hearing controls. Participants completed a minimal two-word grammaticality-judgment task designed to reduce sentence-level working-memory demands while EEG was recorded at the onset of the second word. Accuracy was near ceiling, but the HL group responded more slowly than both hearing comparison groups, and higher working-memory scores were associated with better accuracy within the HL group. In unified ERP models, incongruent pairs elicited overall N400 and P600 effects without interactions with group or construction. Earlier components showed no reliable HL-specific violation pattern. Under these low working-memory demands, later neural responses to minimal agreement violations were detectable at the sample level, while the HL group showed slower behavioral responding and a within-group association between working memory and accuracy.