Visual versus Verbal Working Memory in Statistically Determined Patients with Mild Cognitive Impairment: On behalf of the Consortium for Clinical and Epidemiological Neuropsychological Data Analysis (CENDA)

Abstract

Objective:Previous research in mild cognitive impairment (MCI) suggests that visual episodic memory impairment may emerge before analogous verbal episodic memory impairment. The current study examined working memory (WM) test performance in MCI to assess whether patients present with greater visual versus verbal WM impairment. WM performance was also assessed in relation to hippocampal occupancy (HO), a ratio of hippocampal volume to ventricular dilation adjusted for demographic variables and intracranial volume.Methods:Jak et al. (2009) (The American Journal of Geriatric Psychiatry, 17, 368–375) and Edmonds, Delano-Wood, Galasko, Salmon, & Bondi (2015) (Journal of Alzheimer’s Disease, 47(1), 231–242) criteria classify patients into four groups: little to no cognitive impairment (non-MCI); subtle cognitive impairment (SCI); amnestic MCI (aMCI); and a combined mixed/dysexecutive MCI (mixed/dys MCI). WM was assessed using co-normed Wechsler Adult Intelligence Scale-IV (WAIS-IV) Digit Span Backwards and Wechsler Memory Scale-IV (WMS-IV) Symbol Span Z-scores.Results:Between-group analyses found worse WMS-IV Symbol Span and WAIS-IV Digit Span Backwards performance for mixed/dys MCI compared to non-MCI patients. Within-group analyses found no differences for non-MCI patients; however, all other groups scored lower on WMS-IV Symbol Span than WAIS-IV Digit Span Backwards. Regression analysis with HO as the dependent variable was statistically significant for WMS-IV Symbol Span performance. WAIS-IV Digit Span Backwards performance failed to reach statistical significance.Conclusions:Worse WMS-IV Symbol Span performance was observed in patient groups with measurable neuropsychological impairment and better WMS-IV Symbol Span performance was associated with higher HO ratios. These results suggest that visual WM may be particularly sensitive to emergent illness compared to analogous verbal WM tests.

The effects of six months Persicaria minor extract supplement among older adults with mild cognitive impairment: a double-blinded, randomized, and placebo-controlled trial

“…Nevertheless, we did not find any significant improvements in other cognitive domains. It could be due to the visual working memory impairment that emerged before the verbal working memory impairment among individuals with MCI as suggested by Emrani et al [ 39 ]. Therefore, the effect of the P. minor extract supplement may be more notable in the visual memory domain as compared to other cognitive domains in this study.…”

Machine Learning Analysis of Digital Clock Drawing Test Performance for Differential Classification of Mild Cognitive Impairment Subtypes Versus Alzheimer’s Disease

“…The goal of the current research was to determine how well machine analytic techniques could classify AD patients, non-MCI patients, amnestic MCI, and combined mixed/dys MCI patents into their respective subtypes. Prior research has demonstrated that non-MCI and selected MCI subtypes can be differentiated using tests assessing mental manipulation (Emrani et al, 2018), verbal versus visual working memory (Emrani et al, 2019), verbal versus visual episodic memory (Wasserman et al, 2019), and selected visuospatial operations (Wasserman et al, submitted). These data are compelling on the basis of the neurocognitive constructs that are assessed and differentiated between groups.…”

“…There is considerable interest in the diagnosis and characterization of mild cognitive impairment (MCI), a syndrome believed to be a prodrome often leading to dementia. A variety of MCI subtypes have been identified, including patients presenting with single-domain syndromes such as amnestic (aMCI) and dysexecutive (dys MCI) and a combined or mixed (mixed MCI) phenotype (Emrani et al, 2019;Eppig et al, 2012;Libon et al, 2011). Past research suggests varying rates of conversion to dementia and reversion to normal cognitive functioning depending on MCI subtype (Aerts et al, 2017;Díaz-Mardomingo, García-Herranz, Rodríguez-Fernández, Venero, & Peraita, 2017;Pandya, Lacritz, Weiner, Deschner, & Woon, 2017;Shimada, Doi, Lee, & Makizako, 2019).…”

Verbal and spatial memory spans in mild cognitive impairment

“…Some of these studies documented that performance on span tasks was predictive of conversion to AD at follow‐up 26,27 . Finally, in studies that considered the severity of cognitive impairment, multiple‐domain MCI patients quite consistently obtained reduced span scores with respect to single‐domain amnestic MCI patients 23 …”

“…The few studies that focussed on span tests reported quite controversial data, which is likely due to the adoption of discrepant span procedures and variability in the experimental samples recruited. Indeed, although some studies reported significantly lower span scores in MCI patients than healthy controls, especially when span tasks with more demanding procedures were used, 22,23 other studies failed to report significant differences, both for simpler and more complex paradigms 24,25 . Some of these studies documented that performance on span tasks was predictive of conversion to AD at follow‐up 26,27 .…”