SENTENCE COMPREHENSION IN ALZHEIMERS-DISEASE - EFFECTS OF GRAMMATICALCOMPLEXITY, SPEECH RATE, AND REPETITION

Caregivers of patients diagnosed with Alzheimer's disease (AD) are oft en advised to modify their speech to facilitate the patients' sentence comprehension. Three common recommendations are to (a) speak in simpl e sentences, (b) speak slowly, and (c) repeat one's utterance, using t he same words. These three speech modifications were experimentally ma nipulated in order to investigate their individual and combined effect s on sentence comprehension in AD. Fifteen patients with mild to moder ate AD and 20 healthy older persons were tested on a sentence comprehe nsion task with sentences varying in terms of(a) degree of grammatical complexity, (b) rate of presentation (normal vs, slow), and (c) form of repetition (verbatim vs. paraphrase). The results indicated a signi ficant decline in sentence comprehension for the AD group. Sentence co mprehension improved, however, after the sentence was repeated in eith er verbatim or paraphrased form. However, the patients' comprehension did not improve for sentences presented at the slow speech rate. This pattern of results is explained vis-a-vis the patients' working memory loss. The findings challenge the appropriateness of several clinical recommendations.