Semantic memory evolution in childhood vs its involution in Alzheimer's disease patients.

Thursday 10 September 2015
P20 Semantic memory evolution in childhood vs its involution in Alzheimer's disease Patients
Frouin, C. Université Lumière Lyon 2, Dynamique Du Langage (UMR 5596), Université de Lyon, LabEx Aslan, CNRS Simoes Loureiro, I. Umons, Service de Psychologie Cognitive et Neuropsychologie Gayraud, F. Université Lumière Lyon 2, Dynamique Du Langage (UMR 5596), Université de Lyon, LabEx Aslan, CNRS Lefebvre, L. Umons, Service de Psychologie Cognitive et Neuropsychologie
Objective: According to the retrogenesis hypothesis (Reisberg et al., 2002), the comparison of some dimensions of the cognitive functioning between children and Alzheimer's disease patients (AD) shows an inverse evolution pattern. The purpose of this research is to contribute to a better comprehension of semantic memory. We particularly focus on thematic and taxonomic links because they are predominant in the development of concepts in children and always play an important role in the lexico-semantic processing in adults.
Participants and methods: In the first study, the performances of 40 AD and 20 healthy elderly controls in two 1-minute fluency task and a 24 picture-naming task are analysed. Globally, AD produced fewer words and more errors than controls. They generated more frequent and earlier acquired words in the fluency tasks. In the picture-naming task, errors of the AD were on the late acquired and non-frequent words.
In the second study, we create a unique experimental paradigm adapted to children and AD patients with a semantic knowledge questionnaire and a naming priming paradigm in a thematic and taxonomic condition. The first results conducted in 45 AD patients at 3 different semantic deterioration stages show an interaction effect between the groups and the condition indicating that semantic deterioration does not follow the same pattern for taxonomic and thematic conditions.
Conclusion: AD show a specific lexico-semantic deterioration with an inverse pattern evolution in free lexical production. Priming experiences also suggest a taxonomic and thematic specific deterioration.
The first two authors contribute equally to this work.