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Updated: Jun 26, 2026

The 4 Mountains Test: A Short Test of Spatial Memory with High Sensitivity for the Diagnosis of Pre-dementia Alzheimer's Disease
Published on: October 13, 2016
[Non-verbal memory impairment in Alzheimer-type dementia: Forgetting or acquisition?]
Israel Contador-Castillo1, Bernardino Fernández-Calvo, Francisco Ramos Campos
1Universidad de Salamanca, Spain.
Abstract:
Non-verbal memory impairment in Alzheimer-type dementia: Forgetting or acquisition?. The research aims to compare patients diagnosed with early Alzheimer's disease (AD) and unipolar major depression (D) with a healthy control group (HS) on diverse nonverbal memory tasks (NVM), recall of position, and recognition of abstracts designs. All participants completed a global protocol for diagnosis of dementia. The patients with early AD (n= 27) and D (n= 19) were compared with the healthy subject group (n= 30) on a standardised visuospatial learning test. The AD patients scored significantly lower than HS and D on NVM tasks, but there were no significant differences between AD and D on position recall. Furthermore, the AD group did not show faster forgetting rates on position recall or design recognition in comparison to HS and D groups. These results are interpreted in terms of neurocognitive processes that explain NVM impairment in AD and depression.
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