A SEMantic and EPisodic Memory Test (SEMEP) Developed within the Embodied Cognition Framework: Application to Normal Aging, Alzheimer's Disease and Semantic Dementia

Abstract

Embodiment has highlighted the importance of sensory-motor components in cognition. Perception and memory are thus very tightly bound together, and episodic and semantic memories should rely on the same grounded memory traces. Reduced perception should then directly reduce the ability to encode and retrieve an episodic memory, as in normal aging. Multimodal integration deficits, as in Alzheimer's disease, should lead to more severe episodic memory impairment. The present study introduces a new memory test developed to take into account these assumptions. The SEMEP (SEMantic-Episodic) memory test proposes to assess conjointly semantic and episodic knowledge across multiple tasks: semantic matching, naming, free recall, and recognition. The performance of young adults is compared to healthy elderly adults (HE), patients with Alzheimer's disease (AD), and patients with semantic dementia (SD). The results show specific patterns of performance between the groups. HE commit memory errors only for presented but not to be remembered items. AD patients present the worst episodic memory performance associated with intrusion errors (recall or recognition of items never presented). They were the only group to not benefit from a visual isolation (addition of a yellow background), a method known to increase the distinctiveness of the memory traces. Finally, SD patients suffer from the most severe semantic impairment. To conclude, confusion errors are common across all the elderly groups, whereas AD was the only group to exhibit regular intrusion errors and SD patients to show severe semantic impairment.

Novelty processing and memory impairment in Alzheimer's disease: A review

“…Disappearance of the von Restorff effect with perceptual distinctiveness (Vallet et al, 2017;Vitali et al, 2006) Diminished, but not abolished, benefit of memory for novel over familiarized items; related to hippocampal integrity (Lekeu et al, 2003) MCI: intact recognition memory for novel items (Belleville et al, 2011).…”

“…Furthermore, there was no correlation between sensitivity to novelty and overall memory performance, indicating that the absence of the novelty effect on memory was not related to the memory impairment itself. Recently, Vallet et al (2017) also showed that mild to moderate AD patients (MMSE range: 18-27) did not display better memory for isolated items (a small number of pictures presented on a yellow background) compared to nonisolated items (many pictures on a white background). In light of the retrieval cue hypothesis (Nairne, 2006), it may be that AD patients failed to benefit from the reduced interference linked to the novel retrieval cue compared to control items, possibly because less control items competed at retrieval.…”

Mirror neurons and their relationship with neurodegenerative disorders

“…This view is supported both by data coming from PD studies (Anders et al, ) and by recent data on the MCI/AD spectrum (Farina et. al., ; Moretti, ; Vallet et al, ).…”

A Pilot Tool of the Virtual Scenario Initial Dementia Cognitive Screening (VSIDCS) with a Cultural Exhibition for Improving the Standard Traditional Test

“…Among the many aging phenomena, memory decline of varying degrees is the most commonly observed sign of dementia. Regardless of whether it is a healthy older adult or a person with a neurological disease, their earliest memory deterioration is usually an episodic memory deficit [ 8 ]. Due to the high correlation between perception and episodic memory, the decline in perception ability due to aging directly reduces the ability to encode and retrieve episodic memories.…”