Experimentally disentangling what's beneficial about elderspeak from what's not.

Three studies evaluated different varieties of elderspeak using a referential communication task. Experiment 1 compared the effects of syntactic simplifications and semantic elaborations. Experiment 2 contrasted syntactic simplifications and prosodic exaggerations. Experiment 3 contrasted 2 different syntactic simplification strategies and 2 different prosodic exaggerations. Providing semantic elaborations and reducing the use of subordinate and embedded clauses benefit older adults and improve their performance on the referential communication task, whereas reducing sentence length, slowing speaking rate, and using high pitch do not. The use of short sentences, a slow rate of speaking, and high pitch resulted in older adults' reporting more communication problems. These experiments validate a version of elderspeak that benefits older adults without sounding patronizing and insulting.