Hippocampal atrophy and verbal episodic memory performance in amnestic mild cognitive impairment and mild Alzheimer's disease: A preliminary study

Abstract

To evaluate hippocampal volume in patients with AD and aMCI, and correlate its atrophy with verbal episodic memory performance.MethodsWe studied 42 individuals older than 50 years, including 14 with amnestic mild cognitive impairment (aMCI), 14 with mild Alzheimer’s disease (AD) and 14 normal controls. All individuals were submitted to the Rey auditory verbal learning test (RAVLT) to evaluate episodic memory. They were also submitted to the forward (FDS) and backward digit span (BDS) subtest of WAIS-R to evaluate working memory and attention, and to the Mini Mental State Examination (MMSE). Hippocampal volumetric measurements were performed according to anatomic guidelines from a standard protocol using high-resolution T1-inversion recovery 3-mm coronal MRI slices. Hippocampal volumes (HV) were corrected for the variation in total intracranial volume. There was no significant difference between the three groups concerning age and education.ResultsOn RAVLT, there was a continuum between the three groups, with AD recalling less words, controls more, and aMCI subjects showing an intermediate performance on all sub-items. We found an asymmetry between HVs, with smaller mean left HV for all groups. ANOVA and post hoc Tukey’s test for comparisons of HV showed a significant difference among groups, with difference between controls and both AD and aMCI, although there was no significant difference between AD and aMCI groups.ConclusionsThere was a significant correlation between hippocampal volumes and scores on RAVLT, confirming that medial temporal structures are closely associated with memory performance in normal ageing as well as in aMCI and AD.

Efficacy of Tai Chi-Style Multi-Component Exercise on Frontal-Related Cognition and Physical Health in Elderly With Amnestic Mild Cognitive Impairment

“…The aMCIdementia conversion rate is 10-15% per year, compounding to 80% after 6 years (Petersen, 2000;Petersen et al, 2001). Previous behavioral studies had identified that patients with aMCI showed declined neurocognitive function associated with episodic memory, including immediate and delayed recall, and such poor performance in memory significantly correlated with reduced hippocampal volume compared with healthy older adults (Marchiani et al, 2008;Salmon, 2012;Gainotti et al, 2014). The failure of these basic memory functions for older adults lead to the difficulties in maintaining activities of daily living, the subsequent loss of independence, and the reduction of physical as well psychological health.…”

Usefulness of Discriminability and Response Bias Indices for the Evaluation of Recognition Memory in Mild Cognitive Impairment and Alzheimer Disease

“…For example, most studies simplify recognition memory assessment by only registering the number of correct identifications (i.e., ‘‘hits'') [15]. Other researchers report a corrected measure: hits minus false alarms [16,17], or percent of correct recognitions [18,19] or through nonparametric methods [20]. …”

Story Memory Impairment Rates and Association with Hippocampal Volumes in a Memory Clinic Population

“…For example, previous work in this area found that list learning was better at distinguishing cognitively normal individuals from those with MCI, as compared to story memory (Rabin et al, 2009). Although studies have found associations between individual episodic memory tests and hippocampal volumes in cognitively normal older adults (Hackert et al, 2002;Rosen et al, 2003;Zimmerman et al, 2008) and in individuals with AD (Marchiani, Balthazar, Cendes, & Damasceno, 2008;Sarazin et al, 2010), direct comparisons between structured and unstructured verbal memory tests in terms of their association with underlying cortical areas are limited. Ezzati et al (2016) found that, among cognitively healthy older adults, list learning performance was associated with total and left hippocampal volume, whereas paragraph recall was not significantly related to hippocampal volumes, consistent with other studies in healthy older adults (Marquis et al, 2002;Rodrigue & Raz, 2004).…”