Object-Based Practice Effects Recover the Graphic Object Concept in Alzheimer’s Dementia

Abstract

INTRODUCTION: Dementia is often accompanied by deficits in visual and spatial cognition (e.g. Mielke et al., 1995; Rizzo et al., 2000). We investigated whether the degenerative process could be halted or reversed by daily cognitive exercises. METHOD: Ten older participants with dementia and ten healthy controls were trained on five consecutive days with computerised visual cognition and drawing tasks using the same ten objects (item-based learning). The three visuo-cognitive domains were Semantic Memory (SEM), Scene Perception (SP), and Drawing (DWG). RESULTS: Dementia patients narrowed or closed the gap to healthy controls as reaction time decreased and accuracy increased. In accuracy, the gap closed earlier in SEM than in SP, while in reaction time, gaps were narrowed considerably but persisted. In drawing, the gap in accuracy narrowed and lost object concepts could re-emerge. DISCUSSION: We obtained significant item-specific training effects across tasks feeding into an object-specific neural network.