Specific Features of Executive Dysfunction in Alzheimer-Type Mild Dementia Based on Computerized Cambridge Neuropsychological Test Automated Battery (CANTAB) Test Results

Abstract

BackgroundThe primary manifestation of Alzheimer’s disease (AD) is decline in memory. Dysexecutive symptoms have tremendous impact on functional activities and quality of life. Data regarding frontal-executive dysfunction in mild AD are controversial. The aim of this study was to assess the presence and specific features of executive dysfunction in mild AD based on Cambridge Neuropsychological Test Automated Battery (CANTAB) results.Material/MethodsFifty newly diagnosed, treatment-naïve, mild, late-onset AD patients (MMSE ≥20, AD group) and 25 control subjects (CG group) were recruited in this prospective, cross-sectional study. The CANTAB tests CRT, SOC, PAL, SWM were used for in-depth cognitive assessment. Comparisons were performed using the t test or Mann--Whitney U test, as appropriate. Correlations were evaluated by Pearson r or Spearman R. Statistical significance was set at p<0.05.ResultsAD and CG groups did not differ according to age, education, gender, or depression. Few differences were found between groups in the SOC test for performance measures: Mean moves (minimum 3 moves): AD (Rank Sum=2227), CG (Rank Sum=623), p<0.001. However, all SOC test time measures differed significantly between groups: SOC Mean subsequent thinking time (4 moves): AD (Rank Sum=2406), CG (Rank Sum=444), p<0.001. Correlations were weak between executive function (SOC) and episodic/working memory (PAL, SWM) (R=0.01–0.38) or attention/psychomotor speed (CRT) (R=0.02–0.37).ConclusionsFrontal-executive functions are impaired in mild AD patients. Executive dysfunction is highly prominent in time measures, but minimal in performance measures. Executive disorders do not correlate with a decline in episodic and working memory or psychomotor speed in mild AD.

Differences among patients with Alzheimer's disease, older adults with mild cognitive impairment and healthy older adults in finger dexterity

“…This present study therefore devised and assessed a method for simple, fast measurement of finger movements using a tablet application for detecting finger motion (JustTouch; Hitachi Maxell, Tokyo, Japan) to measure the finger motor skills of dementia patients. Several prior studies reported the use of smart terminals for dementia patients, but did not focus on cognitive functions . The assessment of finger motor skills in the present study thus represents a new approach that could ultimately lead to the construction of a measurement system with a smart terminal device that would enable screening of older groups in health classes and other gatherings.…”

“…Several prior studies reported the use of smart terminals for dementia patients, but did not focus on cognitive functions. 8,9 The assessment of finger motor skills in the present study thus represents a new approach that could ultimately lead to the construction of a measurement system with a smart terminal device that would enable screening of older groups in health classes and other gatherings.…”

Role of Executive Functions in the Conversion from Mild Cognitive Impairment to Dementia

“…They suggested that such groups follow different disease trajectories [5,20]. Kuzmickienè and Kaubrys [17] confirmed that executive disorders could have worse effects on ADL and quality of life of patients than memory disorders and explained that the main feature of dysexecutive function is cognitive slowing.…”

“…In addition, memory decline could predict the transit from normal cognitive functioning to MCI and from MCI to dementia in ACS [13][14][15][16]. However, memory is not the only cognitive function that decline early in Alzheimer's disease [5,8,17]. This has led to investigate whether the combined assessment of episodic memory and other cognitive domains, such as executive functioning, could increase sensitivity and reliability [9,12,[18][19][20].…”

The Number Symbol Coding Task: A brief measure of executive function to detect dementia and cognitive impairment

“…Executive dysfunction in MCI and early stage ADRD may be an important but overlooked construct. Executive dysfunction may have significant impact on activities of daily living and quality of life, perhaps more so than memory impairment [57][58][59][60]. We previously demonstrated transitions in performance on traditional executive and attention tasks such as Trailmaking A and B, Block Design, and Visual Retention tests [61] occur up to three years prior to clinical diagnosis of MCI and dementia in individuals who eventually developed AD dementia [12] and Parkinson's disease dementia [62,63].…”