Neurocognitive Constructs Underlying Executive Control in Statistically-Determined Mild Cognitive Impairment

2021 ◽  
Vol 82 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Sheina Emrani ◽  
Melissa Lamar ◽  
Catherine Price ◽  
Satya Baliga ◽  
Victor Wasserman ◽  
...  
Keyword(s):  
Working Memory ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Inhibitory Control ◽  
Executive Control ◽  
Serial Order ◽  
Temporal Organization ◽  
Executive Attention ◽  
Span Test ◽  
Preparatory Set

Background: The model of executive attention proposes that temporal organization, i.e., the time necessary to bring novel tasks to fruition is an important construct that modulates executive control. Subordinate to temporal organization are the constructs of working memory, preparatory set, and inhibitory control. Objective: The current research operationally-defined the constructs underlying the theory of executive attention using intra-component latencies (i.e., reaction times) from a 5-span backward digit test from patients with suspected mild cognitive impairment (MCI). Methods: An iPad-version of the Backward Digit Span Test (BDT) was administered to memory clinic patients. Patients with (n = 22) and without (n = 36) MCI were classified. Outcome variables included intra-component latencies for all correct 5-span serial order responses. Results: Average total time did not differ. A significant 2-group by 5-serial order latency interaction revealed the existence of distinct time epochs. Non-MCI patients produced slower latencies on initial (position 2-working memory/preparatory set) and latter (position 4-inhibitory control) correct serial order responses. By contrast, patients with MCI produced a slower latency for middle serial order responses (i.e., position 3-preparatory set). No group differences were obtained for incorrect 5-span test trials. Conclusion: The analysis of 5-span BDT serial order latencies found distinct epochs regarding how time was allocated in the context of successful test performance. Intra-component latencies obtained from tests assessing mental re-ordering may constitute useful neurocognitive biomarkers for emergent neurodegenerative illness.

scholarly journals Assessing the capacity for mental manipulation in patients with statically-determined mild cognitive impairment using digital technology

2021 ◽  
Author(s):  
Sheina Emrani ◽  
Melissa Lamar ◽  
Catherine C. Price ◽  
Satya Baliga ◽  
Victor Wasserman ◽  
...  
Keyword(s):  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Time Allocation ◽  
Digit Span ◽  
Serial Order ◽  
Executive Attention ◽  
Memory Clinic ◽  
Digital Version ◽  
Digit Span Test ◽  
Span Test

Aims: Prior research employing a standard backward digit span test has been successful in operationally defining neurocognitive constructs associated with the Fuster’s model of executive attention. The current research sought to test if similar behavior could be obtained using a cross-modal mental manipulation test. Methods: Memory clinic patients were studied. Using Jak-Bondi criteria, 24 patients were classified with mild cognitive impairment (MCI), and 33 memory clinic patients did not meet criteria for MCI (i.e. non-MCI). All patients were assessed with the digital version of the WRAML-2 Symbolic Working Memory Test-Part 1, a cross-modal mental manipulation task where patients hear digits, but respond by touching digits from lowest to highest on an answer key. Only 4 and 5-span trials were analyzed. Using an iPad, all test stimuli were played; and, all responses were obtained with a touch key. Only correct trials were analyzed. Average time to complete trials and latency for each digit was recorded. Results: Groups did not differ when average time to complete 4-span trials was calculated. MCI patients displayed slower latency, or required more time to re-order the 1st and 3rd digits. Regression analyses, primarily involving initial and latter response latencies, were associated with better, but different underlying neuropsychological abilities. Almost no 5-span analyses were significant. Conclusions: This cross-modal test paradigm found no difference for total average time. MCI patients generated slower 1st and 3rd response latency, suggesting differences in time allocation to achieve correct serial order recall. Moreover, different neuropsychological abilities were associated with different time-based test components. These data extend prior findings using a standard backward digit span test. Differences in time epochs are consistent with constructs underlying the model of executive attention and help explain mental manipulation deficits in MCI. These latency measures could constitute neurocognitive biomarkers that track emergent disease.

Learning and memory in amnestic mild cognitive impairment: Contribution of working memory

2010 ◽  
Vol 16 (2) ◽  
pp. 342-351 ◽  
Author(s):  
SARAH E. PRICE ◽  
GLYNDA J. KINSELLA ◽  
BEN ONG ◽  
ELIZABETH MULLALY ◽  
MARGARET PHILLIPS ◽  
...  
Keyword(s):  
Working Memory ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Verbal Fluency ◽  
Amnestic Mild Cognitive Impairment ◽  
Executive Attention ◽  
Semantic Clustering ◽  
Episodic Buffer ◽  
Amci Group ◽  
Encoding Strategies

AbstractIn addition to deficits in delayed recall, recent research suggests that participants with amnestic mild cognitive impairment (aMCI) demonstrate diminished use of strategic encoding strategies during learning. Few studies have explored the cognitive mechanisms underlying this deficit. The aim of this study was to investigate in aMCI whether components of working memory (executive attention – attention set-shifting, dividing and focusing attention; and episodic buffer functions – strategic retrieval and manipulation of information) predict strategic encoding strategies during learning (semantic clustering). Thirty-three participants with aMCI and 33 healthy older adults (HOA) were administered neuropsychological tests assessing word-list learning and working memory. The aMCI group demonstrated significant impairment in acquisition, retrieval of information, and decreased use of semantic clustering strategies. Use of semantic clustering in the aMCI group was not predicted by measures of executive attention or phonemic verbal fluency, but was predicted by semantic verbal fluency performance. In the HOA group, semantic clustering was strongly related to semantic verbal fluency. These findings suggest that in aMCI, diminished strategic encoding strategies during learning (semantic clustering) is selectively related to the strategic function of the episodic buffer, but only when in interaction with the manipulation and retrieval of semantic associations. (JINS, 2010, 16, 342–351.)

scholarly journals Assessing Working Memory in Mild Cognitive Impairment with Serial Order Recall

2018 ◽  
Vol 61 (3) ◽  
pp. 917-928 ◽  
Author(s):  
Sheina Emrani ◽  
David J. Libon ◽  
Melissa Lamar ◽  
Catherine C. Price ◽  
Angela L. Jefferson ◽  
...  
Keyword(s):  
Working Memory ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Serial Order

scholarly journals Memory-Related Frontal Brainwaves Predict Transition to Mild Cognitive Impairment in Healthy Older Individuals Five Years Before Diagnosis

2020 ◽  
pp. 1-11
Author(s):  
Yang Jiang ◽  
Juan Li ◽  
Frederick A. Schmitt ◽  
Gregory A. Jicha ◽  
Nancy B. Munro ◽  
...  
Keyword(s):  
Older Adults ◽  
Working Memory ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Memory Performance ◽  
Memory Task ◽  
Cognitive Status ◽  
Older Individuals ◽  
Increased Risk ◽  
Differentiation Pattern

Background: Early prognosis of high-risk older adults for amnestic mild cognitive impairment (aMCI), using noninvasive and sensitive neuromarkers, is key for early prevention of Alzheimer’s disease. We have developed individualized measures in electrophysiological brain signals during working memory that distinguish patients with aMCI from age-matched cognitively intact older individuals. Objective: Here we test longitudinally the prognosis of the baseline neuromarkers for aMCI risk. We hypothesized that the older individuals diagnosed with incident aMCI already have aMCI-like brain signatures years before diagnosis. Methods: Electroencephalogram (EEG) and memory performance were recorded during a working memory task at baseline. The individualized baseline neuromarkers, annual cognitive status, and longitudinal changes in memory recall scores up to 10 years were analyzed. Results: Seven of the 19 cognitively normal older adults were diagnosed with incident aMCI for a median 5.2 years later. The seven converters’ frontal brainwaves were statistically identical to those patients with diagnosed aMCI (n = 14) at baseline. Importantly, the converters’ baseline memory-related brainwaves (reduced mean frontal responses to memory targets) were significantly different from those who remained normal. Furthermore, differentiation pattern of left frontal memory-related responses (targets versus nontargets) was associated with an increased risk hazard of aMCI (HR = 1.47, 95% CI 1.03, 2.08). Conclusion: The memory-related neuromarkers detect MCI-like brain signatures about five years before diagnosis. The individualized frontal neuromarkers index increased MCI risk at baseline. These noninvasive neuromarkers during our Bluegrass memory task have great potential to be used repeatedly for individualized prognosis of MCI risk and progression before clinical diagnosis.

Sign in / Sign up

Export Citation Format

Share Document