Inter-method and anatomical correlates of episodic memory tests in the Alzheimer’s Disease spectrum

Abstract

BackgroundEpisodic memory impairments have been described as initial clinical findings in the Alzheimer’s Disease (AD) spectrum, which could be associated with the presence of early hippocampal dysfunction. However, correlates between performances in neuropsychological tests and hippocampal volumes in AD were inconclusive in the literature. Divergent methods to assess episodic memory have been depicted as a major source of heterogeneity across studies.MethodsWe examined correlates among performances in three different delayed-recall tasks (Rey-Auditory Verbal-Learning Test–RAVLT, Logical Memory and Visual Reproduction subtests from the Wechsler Memory Scale) and fully-automated volumetric measurements of the hippocampus (estimated using Neuroquant®) of 83 older subjects (47 controls, 27 Mild Cognitive Impairment individuals and 9 participants with Dementia due to AD).ResultsInter-method correlations of episodic memory performances were at most moderate. Scores in the RAVLT predicted up to 48% of variance in HOC (Hippocampal Occupancy Score) among subjects in the AD spectrum.DiscussionTests using different stimuli (verbal or visual) and presenting distinct designs (word list, story or figure learning) may assess divergent aspects in episodic memory, with heterogeneous anatomical correlates.ConclusionsDifferent episodic memory tests might not assess the same construct and should not be used interchangeably. Scores in RAVLT may correlate with the presence of neurodegeneration in AD.

Automatization and validation of the hippocampal-to-ventricle ratio in a clinical sample

“…We found such a relation in our MCI subgroup for all segmentation methods, but not in the cognitively normal or AD groups. These results contrasted with previous reported relationships in AD between the delayed subtest of RAVLT with HOC in a Brazilian sample (Sudo et al 2019) and with HCvol within ADNI (X. Wang et al 2019).…”

Structural and Functional Hippocampal Changes in Subjective Cognitive Decline From the Community

“…It is universally known that episodic memory is the first cognitive domain involved in the AD spectrum and the most sensitive neuropsychological indicator for early AD (Dubois et al, 2007). The AD pattern of gray matter was found in SCD which correlated with episodic memory decline (Peter et al, 2014), and RAVLT demonstrated significant association with the Hippocampal Occupancy Score and hippocampal volumes in the AD spectrum (Sudo et al, 2019). However, the change of hippocampus tends to be asymmetry in SCD, and the structural MRI studies revealed a decreased volume preferred the right hippocampus (Yue et al, 2018).…”

Associations between cerebrospinal fluid markers and cognition in ageing and dementia: A systematic review

“…As one of the most widely used and accessible imaging methods, it is currently recommended in diagnostic criteria for AD (Jack et al, 2018). T1‐ and T2‐weighted images show different atrophy patterns and white matter alterations across different dementia syndromes (Harper et al, 2017), which all correlate with degree of the cognitive impairment (Bayram et al, 2018; Sudo et al, 2019; Wolk & Dickerson, 2011). The 7T MRI can provide further information about cognitive decline at an ultrahigh resolution, such as hippocampal subfield changes across dementias and MCI (McKiernan & OBrien, 2017).…”