FEATURES OF THE CONFLICT ADAPTATION EFFECT IN MILD COGNITIVE DECLINE

Эффект адаптации к конфликту в задачах на подавление интерференции (таких как задача Струпа или фланговая задача) заключается в улучшении подавления иррелевантных стимулов после их подавления в предыдущей пробе. На материале фланговой задачи показывается, что когнитивное физиологическое старение сопровождается нулевым эффектом адаптации к конфликту, а мягкое когнитивное снижение - обратным (то есть отрицательным) эффектом адаптации к конфликту. Проведенный анализ времени реакции с помощью диффузионной модели ( drift diffusion model ) показал, что изменения в эффекте адаптации к конфликту у пациентов с мягким когнитивным снижением связаны с отсутствием у них адаптивного ускорения скорости переработки стимулов при наличии дистракторов. Этот результат может свидетельствовать о ригидности системы контроля перцептивных процессов, позволяющих осуществлять стратегическое перераспределение внимания в пожилом возрасте и при патологическом старении. Делается вывод о возможной роли обратного (отрицательного) эффекта адаптации к конфликту как раннего индикатора патологической когнитивной дисфункции. Conﬂict adaptation effect in interference control tasks (like Stroop task or ﬂanker task) consists in better interference suppression in incongruent trials following an incongruent trial. In a ﬂanker task is shown that in normal cognitive aging there is a null conﬂict adaptation effect and that in mild cognitive impairment there is a reversed (negative) conﬂict adaptation effect. Using the drift diffusion model of reaction time, it is shown that the change in conﬂict adaptation effect in mild cognitive impairment is associated with the absence of adaptive increase in processing speed in the presence of distractors. This can be interpreted as the rigidity of perceptual control mechanisms, which are responsible for strategic distribution of attention in older age and in pathological aging, in particular. The conclusion is drawn that reversed conﬂict adaptation effect may be an early marker of pathological cognitive aging.

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Visuo-Perceptual and Decision-Making Contributions to Visual Hallucinations in Mild Cognitive Impairment in Lewy Body Disease: Insights from a Drift Diffusion Analysis

Brain Sciences ◽

10.3390/brainsci10080540 ◽

2020 ◽

Vol 10 (8) ◽

pp. 540

Author(s):

Lauren Revie ◽

Calum A Hamilton ◽

Joanna Ciafone ◽

Paul C Donaghy ◽

Alan Thomas ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Reaction Time ◽

Diffusion Model ◽

Lewy Body ◽

Drift Rate ◽

Lewy Body Disease ◽

Visual Hallucinations ◽

Drift Diffusion Model ◽

Drift Diffusion

Background: Visual hallucinations (VH) are a common symptom in dementia with Lewy bodies (DLB); however, their cognitive underpinnings remain unclear. Hallucinations have been related to cognitive slowing in DLB and may arise due to impaired sensory input, dysregulation in top-down influences over perception, or an imbalance between the two, resulting in false visual inferences. Methods: Here we employed a drift diffusion model yielding estimates of perceptual encoding time, decision threshold, and drift rate of evidence accumulation to (i) investigate the nature of DLB-related slowing of responses and (ii) their relationship to visuospatial performance and visual hallucinations. The EZ drift diffusion model was fitted to mean reaction time (RT), accuracy and RT variance from two-choice reaction time (CRT) tasks and data were compared between groups of mild cognitive impairment (MCI-LB) LB patients (n = 49) and healthy older adults (n = 25). Results: No difference was detected in drift rate between patients and controls, but MCI-LB patients showed slower non-decision times and boundary separation values than control participants. Furthermore, non-decision time was negatively correlated with visuospatial performance in MCI-LB, and score on visual hallucinations inventory. However, only boundary separation was related to clinical incidence of visual hallucinations. Conclusions: These results suggest that a primary impairment in perceptual encoding may contribute to the visuospatial performance, however a more cautious response strategy may be related to visual hallucinations in Lewy body disease. Interestingly, MCI-LB patients showed no impairment in information processing ability, suggesting that, when perceptual encoding was successful, patients were able to normally process information, potentially explaining the variability of hallucination incidence.

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Drift Diffusion Model of Animacy Categorization Task Can Detect Patients with Mild Cognitive Impairment and Mild Alzheimer's Disease

Frontiers in Biomedical Technologies ◽

10.18502/fbt.v8i1.5857 ◽

2021 ◽

Author(s):

Hamed Karimi ◽

Haniye Marefat ◽

Mahdiye Khanbagi ◽

Alireza Karami ◽

Zahra Vahabi

Keyword(s):

Alzheimer’S Disease ◽

Decision Making ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Diffusion Model ◽

Computational Approach ◽

Drift Diffusion Model ◽

Drift Diffusion ◽

Categorization Task ◽

Early Stages

Purpose: The process of neurodegeneration in Alzheimer's Disease (AD) is irreversible using current therapeutics. An earlier diagnosis of the disease can lead to earlier interventions, which will help patients sustain their cognitive abilities for longer. Individuals within the early stages of AD, shown to have trouble making confident and sounds decisions. Here we proposed a computational approach to quantify the decision-making ability in patients with mild cognitive impairment and mild AD. Materials and Methods: To study the quantified decision-making abilities at the early stages of the disease, we took advantage of a 2-Alternative Forced-Choice (2AFC) task. We applied the Drift Diffusion Model to determine whether the information accumulation process in a categorization task is altered in patients with mild cognitive impairment and mild AD. We implemented a classification model to detect cognitive impairment based on the Drift Diffusion Model's estimated parameters. Results: The results show a significant correlation of the classification score with the standard pen-and-paper tests, suggesting that the quantified decision-making parameters are undergoing significant change in patients with cognitive impairment. Conclusion: We confirmed that the decision-making ability deteriorates at the early stages of AD. We introduced a computational approach for measuring the decline in decision-making and used that measurement to distinguish patients from healthy individuals.

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Identifying Feigned Cognitive Impairment: Investigating the Utility of Diffusion Model Analyses

Assessment ◽

10.1177/1073191120962317 ◽

2020 ◽

pp. 107319112096231

Author(s):

Elad Omer ◽

Tomer Elbaum ◽

Yoram Braw

Keyword(s):

Cognitive Impairment ◽

Diffusion Model ◽

Cognitive Processes ◽

Forced Choice ◽

Model Parameters ◽

Performance Validity ◽

Drift Diffusion Model ◽

Drift Diffusion ◽

Choice Performance ◽

Feigned Cognitive Impairment

Forced-choice performance validity tests are routinely used for the detection of feigned cognitive impairment. The drift diffusion model deconstructs performance into distinct cognitive processes using accuracy and response time measures. It thereby offers a unique approach for gaining insight into examinees’ speed-accuracy trade-offs and the cognitive processes that underlie their performance. The current study is the first to perform such analyses using a well-established forced-choice performance validity test. To achieve this aim, archival data of healthy participants, either simulating cognitive impairment in the Word Memory Test or performing it to the best of their ability, were analyzed using the EZ-diffusion model ( N = 198). The groups differed in the three model parameters, with drift rate emerging as the best predictor of group membership. These findings provide initial evidence for the usefulness of the drift diffusion model in clarifying the cognitive processes underlying feigned cognitive impairment and encourage further research.

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The critical role of interference control in metaphor comprehension evidenced by the drift–diffusion model

Scientific Reports ◽

10.1038/s41598-021-98351-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hee-Dong Yoon ◽

Minho Shin ◽

Hyeon-Ae Jeon

Keyword(s):

Executive Functions ◽

Diffusion Model ◽

Word Association ◽

Response Times ◽

Critical Role ◽

Interference Control ◽

Drift Diffusion Model ◽

Drift Diffusion ◽

Metaphor Comprehension ◽

Fine Grained

AbstractWe address the question of, among several executive functions, which one has a strong influence on metaphor comprehension. To this end, participants took part in a metaphor comprehension task where metaphors had varying levels of familiarity (familiar vs. novel metaphors) with different conditions of context (supporting vs. opposing contexts). We scrutinized each participant’s detailed executive functions using seven neuropsychological tests. More interestingly, we modelled their responses in metaphor comprehension using the drift–diffusion model, in an attempt to provide more systematic accounts of the processes underlying metaphor comprehension. Results showed that there were significant negative correlations between response times in metaphor comprehension and scores of the Controlled Oral Word Association Test (COWAT)-Semantic, suggesting that better performances in comprehending metaphors were strongly associated with better interference control. Using the drift–diffusion model, we found that the familiarity, compared to context, had greater leverage in the decision process for metaphor comprehension. Moreover, individuals with better performance in the COWAT-Semantic test demonstrated higher drift rates. In conclusion, with more fine-grained analysis of the decisions involved in metaphor comprehension using the drift–diffusion model, we argue that interference control plays an important role in processing metaphors.

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EEG Measures of Value-Directed Strategic Processing in Older Adults With and Without Mild Cognitive Impairment

Innovation in Aging ◽

10.1093/geroni/igaa057.937 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

pp. 292-293

Author(s):

Lydia Nguyen ◽

Shraddha Shende ◽

Daniel Llano ◽

Raksha Mudar

Keyword(s):

Older Adults ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Cognitive Aging ◽

Spectral Power ◽

Group Differences ◽

Cognitive Resources ◽

Alpha Power ◽

Strategic Processing ◽

Unique Word

Abstract Value-directed strategic processing is important for daily functioning. It allows selective processing of important information and inhibition of irrelevant information. This ability is relatively preserved in normal cognitive aging, but it is unclear if mild cognitive impairment (MCI) affects strategic processing and its underlying neurophysiological mechanisms. The current study examined behavioral and EEG spectral power differences between 16 cognitively normal older adults (CNOA; mean age: 74.5 ± 4.0 years) and 16 individuals with MCI (mean age: 77.1 ± 4.3 years) linked to a value-directed strategic processing task. The task used five unique word lists where words were assigned high- or low-value based on letter case and were presented sequentially while EEG was recorded. Participants were instructed to recall as many words as possible after each list to maximize their score. Results revealed no group differences in recall of low-value words, but individuals with MCI recalled significantly fewer high-value words and total number of words relative to CNOA. Group differences were observed in theta and alpha bands for low-value words, with greater synchronized theta power for CNOA than MCI and greater desynchronized alpha power for MCI than CNOA. Collectively, these findings demonstrate that more effortful neural processing of low-value words in the MCI group, relative to the CNOA group, allowed them to match their behavioral performance to the CNOA group. Individuals with MCI appear to utilize more cognitive resources to inhibit low-value information and might show memory-related benefits if taught strategies to focus on high-value information processing.

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