The Relational and Item-Specific Encoding Task in Mild Cognitive Impairment and Alzheimer Disease

Background: The Relational and Item-Specific Encoding task (RISE) measures episodic memory subcomponents, including item-specific and relational encoding of to-be-remembered stimuli. These memory components are neurobiologically relevant because they may engage distinct subregions of the medial temporal lobe, perirhinal and entorhinal cortices, parahippocampus, and hippocampus. Methods: A total of 125 participants, including 84 healthy controls (HC), 22 mild cognitive impairment-diagnosed and 19 Alzheimer disease (AD)-diagnosed participants, were administered the RISE and neuropsychological measures. Stepwise linear regressions assessed prediction of functional ability from RISE d′ measures. ANOVAs and logistic regressions determined the ability of the RISE to discriminate between the diagnostic groups. In addition, the psychometric properties of the RISE were examined. Results: RISE measures predicted diagnosis with pseudo R2 values in the range of 0.25-0.30. Receiver operating characteristic curves demonstrated adequate sensitivity and specificity with areas under the curve in the range of 0.78-0.98. Memory following relational encoding was a significant predictor of everyday functional competence. The RISE had acceptable psychometric properties, with the exception of floor effects in the AD group. Conclusion: The RISE measures significantly predicted diagnosis and predicted everyday functional competence. The RISE offers unique advantages in the assessment of HC and individuals with preclinical AD.

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Psychometric Properties of the Persian Montreal Cognitive Assessment in Mild Cognitive Impairment and Alzheimer Disease

Dementia and Geriatric Cognitive Disorders Extra ◽

10.1159/000514673 ◽

2021 ◽

pp. 51-57

Author(s):

Vahid Rashedi ◽

Mahshid Foroughan ◽

Negin Chehrehnegar

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Alzheimer Disease ◽

Psychometric Properties ◽

Cognitive Assessment ◽

Screening Test ◽

Cognitive Status ◽

Montreal Cognitive Assessment ◽

Cutoff Score ◽

Persian Version

Introduction: The Montreal Cognitive Assessment (MoCA) is a cognitive screening test widely used in clinical practice and suited for the detection of Mild Cognitive Impairment (MCI). The aims were to evaluate the psychometric properties of the Persian MoCA as a screening test for mild cognitive dysfunction in Iranian older adults and to assess its accuracy as a screening test for MCI and mild Alzheimer disease (AD). Method: One hundred twenty elderly with a mean age of 73.52 ± 7.46 years participated in this study. Twenty-one subjects had mild AD (MMSE score ≤21), 40 had MCI, and 59 were cognitively healthy controls. All the participants were administered the Mini-Mental State Examination (MMSE) to evaluate their general cognitive status. Also, a battery of comprehensive neuropsychological assessments was administered. Results: The mean score on the Persian version of the MoCA and the MMSE were 19.32 and 25.62 for MCI and 13.71 and 22.14 for AD patients, respectively. Using an optimal cutoff score of 22 the MoCA test detected 86% of MCI subjects, whereas the MMSE with a cutoff score of 26 detected 72% of MCI subjects. In AD patients with a cutoff score of 20, the MoCA had a sensitivity of 94% whereas the MMSE detected 61%. The specificity of the MoCA was 70% and 90% for MCI and AD, respectively. Discussion: The results of this study show that the Persian version of the MoCA is a reliable screening tool for detection of MCI and early stage AD. The MoCA is more sensitive than the MMSE in screening for cognitive impairment, proving it to be superior to MMSE in detecting MCI and mild AD.

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State of the science on mild cognitive impairment (MCI)

CNS Spectrums ◽

10.1017/s1092852918001347 ◽

2019 ◽

Vol 24 (1) ◽

pp. 78-87 ◽

Cited By ~ 7

Author(s):

Nicole D. Anderson

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Social Engagement ◽

Medial Temporal Lobe ◽

Healthy Aging ◽

Cognitive Screening ◽

Symptoms Of Depression ◽

Preclinical Ad ◽

Positron Emission ◽

State Of The Science

Mild cognitive impairment (MCI) represents a transitional stage between healthy aging and dementia, and affects 10–15% of the population over the age of 65. The failure of drug trials in Alzheimer’s disease (AD) treatment has shifted researchers’ focus toward delaying progression from MCI to dementia, which would reduce the prevalence and costs of dementia profoundly. Diagnostic criteria for MCI increasingly emphasize the need for positive biomarkers to detect preclinical AD. The phenomenology of MCI comprises lower quality-of-life, greater symptoms of depression, and avoidant coping strategies including withdrawal from social engagement. Neurobiological features of MCI are hypoperfusion and hypometabolism in temporoparietal cortices, medial temporal lobe atrophy particularly in rhinal cortices, elevated tau and phosphorylated tau and decreased Aβ42in cerebrospinal fluid, and brain Aβ42deposition. Elevated tau can be identified in MCI, particularly in the entorhinal cortex, using positron emission tomography, and analysis of signal complexity using electroencephalography or magnetoencephalography holds promise as a biomarker. Assessment of MCI also relies on cognitive screening and neuropsychological assessment, but there is an urgent need for standardized cognitive tests to capitalize on recent discoveries in cognitive neuroscience that may lead to more sensitive measures of MCI. Cholinesterase inhibitors are frequently prescribed for MCI, despite the lack of evidence for their efficacy. Exercise and diet interventions hold promise for increasing reserve in MCI, and group psychoeducational programs teaching practical memory strategies appear effective. More work is needed to better understand the phenomenology and neurobiology of MCI, and how best to assess it and delay progression to dementia.

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A Lack of Practice Effects on Memory Tasks Predicts Conversion to Alzheimer Disease in Patients With Amnestic Mild Cognitive Impairment

Journal of Geriatric Psychiatry and Neurology ◽

10.1177/0891988720944244 ◽

2020 ◽

pp. 089198872094424

Author(s):

Maria Stefania De Simone ◽

Roberta Perri ◽

Marta Rodini ◽

Lucia Fadda ◽

Massimo De Tollis ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Alzheimer Disease ◽

Test Performance ◽

Medial Temporal Lobe ◽

Amnestic Mild Cognitive Impairment ◽

Practice Effects ◽

Large Set ◽

Neuropsychological Evaluations

The aim of the current study was to test the accuracy of practice effects, that is, improvement in test performance due to repeated neuropsychological evaluations, in identifying patients with amnestic mild cognitive impairment (a-MCI) at greater risk of conversion to Alzheimer disease (AD). For this purpose, we conducted a longitudinal study of 54 patients diagnosed with a-MCI at the first assessment and followed-up for 4 years. During this time, 18 patients converted to AD. Baseline and 6- to 12-month follow-up performances on a large set of neuropsychological tests were analyzed to determine their diagnostic ability to predict later conversion to dementia. Results demonstrate that a lack of practice effects on episodic memory tests is an accurate prognostic indicator of late conversion to AD in a-MCI patients. In fact, even though the performance of both groups was substantially comparable at the baseline evaluation, stable a-MCI patients greatly improved their memory performance at retest after 6 to 12 months; instead, scores of converter a-MCI remained stable or decreased passing from baseline to follow-up. Standardized z-change scores on memory tasks, which were computed as a reliable measure of performance change, classified group membership with very good overall accuracy, which was higher than the classification of converter and stable a-MCIs provided by baseline or follow-up scores. We hypothesize that the lack of practice effects on memory tasks mirrors the early involvement of medial temporal lobe areas in converter a-MCI that are fundamental for the consolidation of new memory traces.

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Automated Volumetry of Medial Temporal Lobe Subregions in Mild Cognitive Impairment and Alzheimer Disease

Alzheimer Disease & Associated Disorders ◽

10.1097/wad.0000000000000318 ◽

2019 ◽

Vol 33 (3) ◽

pp. 206-211 ◽

Cited By ~ 1

Author(s):

Kaori Hata ◽

Kazunori Nakamoto ◽

Akihiko Nunomura ◽

Daichi Sone ◽

Norihide Maikusa ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Alzheimer Disease ◽

Temporal Lobe ◽

Medial Temporal Lobe

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Sensitive Measures of Cognition in Mild Cognitive Impairment

Journal of Alzheimer s Disease ◽

10.3233/jad-201280 ◽

2021 ◽

pp. 1-14

Author(s):

Nathaniel Klooster ◽

Stacey Humphries ◽

Eileen Cardillo ◽

Franziska Hartung ◽

Long Xie ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Semantic Memory ◽

Medial Temporal Lobe ◽

Figurative Language ◽

Neurofibrillary Tangle ◽

Experimental Tests ◽

Perirhinal Cortex ◽

Cognitive Change ◽

Preclinical Ad

Background: Sensitive measures of cognition are needed in preclinical and prodromal Alzheimer’s disease (AD) to track cognitive change and evaluate potential interventions. Neurofibrillary tangle pathology in AD is first observed in Brodmann Area 35 (BA35), the medial portion of the perirhinal cortex. The importance of the perirhinal cortex for semantic memory may explain early impairments of semantics in preclinical AD. Additionally, our research has tied figurative language impairment to neurodegenerative disease. Objective: We aim to identify tasks that are sensitive to cognitive impairment in individuals with mild cognitive impairment (MCI), and that are sensitive to atrophy in BA35. Methods: Individuals with MCI and cognitively normal participants (CN) were tested on productive and receptive experimental measures of semantic memory and experimental tests of figurative language comprehension (including metaphor and verbal analogy). Performance was related to structural imaging and standard neuropsychological assessment. Results: On the experimental tests of semantics and figurative language, people with MCI performed worse than CN participants. The experimental semantic memory tasks are sensitive and specific; performance on the experimental semantic memory tasks related to medial temporal lobe structural integrity, including BA35, while standard neuropsychological assessments of semantic memory did not, demonstrating the sensitivity of these experimental measures. A visuo-spatial analogy task did not differentiate groups, confirming the specificity of semantic and figurative language tasks. Conclusion: These experimental measures appear sensitive to cognitive change and neurodegeneration early in the AD trajectory and may prove useful in tracking cognitive change in clinical trials aimed at early intervention.

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