Investigation of Semantic Facilitation and Interference in Lexical Retrieval in Aging and Alzheimer’s Disease

Speech production requires the activation of semantic representations and the selection of a specific word among semantically related words in a mental lexicon. The literature has mainly explored the impact of semantic interference on lexical retrieval, but the potential beneficial effect of semantic context on this retrieval remains to be explored (Python et al., 2018). Interference is frequently caused by unrelated concepts (e.g. cow-computer). Nevertheless, even when concepts are interconnected, we can observe divergent effects. Indeed, an interference effect would be more marked when the relation between concepts is categorical (e.g. cow-horse), whereas an associative relation (e.g. cow-milk) would facilitate lexical retrieval. The aim of our study is to explore how semantic links can facilitate or interfere with lexical retrieval, while examining how these effects evolve with age. Aging can lead to cognitive difficulties such as a general slowing down and inhibition deficits, more specifically in interference resistance. Two groups will be formed: (1) 30 participants aged 18 to 25 and (2) 30 participants aged over 65. Our experimental protocol will include four conditions relating to the link between the image to be named and the word written over it: (1) a categorical condition (image and word belonging to the same category), (2) an associative condition (image and word sharing a temporality, spatiality, causality or functionality), (3) an unrelated condition (image and word are not semantically linked) and (4) a control condition (image and neutral symbol). The protocol is currently being pre-tested and we will present the preliminary results.