Repetition in dementia: A study on Turkish

Objective: This study investigates the repetition performance of individuals with dementia on a repetition task. Method: The research examines the performance of 30 young adults, 32 senior adults (65+), and 32 individuals diagnosed with dementia on word and pseudoword repetition task. In addition to word repetition, this study also examines sentence repetition task constructed on a length-based scale with manipulations of complexity and reversibility in individuals with dementia. The task used in this study is divided into four main parts: the Mini-Mental State Examination to assess cognitive integrity; forward and backward digit span tests to assess working memory; the Turkish clinical adaptation of the Western Aphasia Battery's word repetition test; a pseudoword test, designed on the basis of the Turkish word repetition task list. Finally, a sentence repetition test constructed on a length-based scale, manipulating subject and object relative clauses and reversible/irreversible parameters. The research was conducted with young (18–64), senior (65+), and dementia-diagnosed participants. Results: Linear mixed modeling showed that semantic meaningfulness was important for correct word repetition in individuals with dementia (dementia group, meaningful word repetition coefficient = −8.119, p < .001, CI = [−11.602, −4.636]; nonword repetition coefficient = −0.300, p < .001, CI = [−0.413, −0.187]). In sentence repetition with relative clauses, object-relative clauses were observed to be more difficult than subject-relative and simple sentence repetition (subject-relative coefficient = −0.123, p = .005, CI = [−0.208, −0.038]; object-relative coefficient = −0.151, p = .001, [−0.236, −0.066]). For reversibility-based sentences, reversible sentences were more difficult (dementia group coefficient = −0.667, p < .001, CI = [−0.863, −0.471]). In addition, sentence- and word-length effects increased in direct proportion to the intactness of working memory. Conclusion: Participants diagnosed with dementia perform worse at pseudoword repetition task than word repetition. It is also demonstrated that participants perform worse at repetition of complex sentence structures than simple structures. While an intact working-memory helped with the repetition of longer words and sentences, and positively affected the repetition of subject and object-relative clauses, the impact was modest rather than significant. Similarly, for reversible sentences, a positive effect was noted, though it was not significant. Keywords: dementia, repetition task, semantics, syntax