P2-131: Relationships between cognitive activity, Alzheimer's disease pathological biomarkers and cognitive functioning in normal older adults

AbstractObjectiveEstimate the time-course of the spread of key pathological markers and the onset of cognitive dysfunction in Alzheimer’s disease.MethodsIn a cohort of 336 older adults, ranging in cognitive functioning, we estimated the time of initial changes of Aβ, tau, and decreases in cognition with respect to the time of Aβ-positivity.ResultsSmall effect sizes of change in CSF Aβ42 and regional Aβ PET were estimated to occur several decades before Aβ-positivity. Increases in CSF tau occurred 11-12 years before Aβ-positivity. Temporoparietal tau PET showed increases 4-5 years before Aβ-positivity. Subtle cognitive dysfunction was observed 7-9 years before Aβ-positivity.ConclusionsIncreases in tau and cognitive dysfunction occur years before the presence of significant Aβ. Explicit estimates of the time for these events provide a clearer picture of the time course of the amyloid cascade and identify potential windows for specific treatments.

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A significant difference of memory beliefs, cognitive activity, and depression in healthy older adults, patients with amnestic mild cognitive impairment, and patients with Alzheimer's disease

Journal of the Neurological Sciences ◽

10.1016/j.jns.2019.10.920 ◽

2019 ◽

Vol 405 ◽

pp. 82

Author(s):

I.U. Song ◽

K.S. Lee ◽

Y.A. Chung ◽

S.W. Chung

Keyword(s):

Alzheimer’S Disease ◽

Older Adults ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Cognitive Activity ◽

Amnestic Mild Cognitive Impairment ◽

Healthy Older Adults ◽

Significant Difference

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p-tau/Aβ42 Ratio Associates with Cognitive Decline in Alzheimer’s disease, Mild Cognitive Impairment, and Cognitively Unimpaired Older Adults

10.1101/2020.10.13.20211375 ◽

2020 ◽

Author(s):

Ruchika Shaurya Prakash ◽

Michael R. McKenna ◽

Oyetunde Gbadeyan ◽

Rebecca Andridge ◽

Douglas W. Scharre ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Older Adults ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Executive Functioning ◽

Episodic Memory ◽

Cognitive Decline ◽

Cognitive Functioning ◽

The Impact

AbstractINTRODUCTIONThe most well-studied biomarkers in AD are CSF amyloid beta-42 (Aβ42), tau, p-tau, and the ratio p-tau/Aβ42. The ratiometric measure of p-tau/Aβ42 shows the best diagnostic accuracy, and correlates reliably with metrics of cognition in unimpaired participants. However, no study has examined the impact of the CSF p-tau/Aβ42 ratio in predicting cognitive decline in both healthy and AD individuals in one sample. The goal of this study was to examine whether CSF-based p-tau/Aβ42 predicts changes in global cognitive functioning, episodic memory, and executive functioning over a two-year period in cognitively impaired older adults (CU), and in individuals with Mild Cognitive Impairment (MCI) and Alzheimer’s disease (AD).METHODSThis study involves secondary analysis of data from 1215 older adults available in the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Neuropsychological variables, collected at baseline, 6-month, 12-month, and 24-month follow-ups, included the Preclinical Alzheimer’s Cognitive Composite (PACC) to assess global cognitive functioning, ADNI-MEM to assess episodic memory functioning, and ADNI-EF to assess executive functioning. Linear mixed models were constructed to examine the effect of CSF p-tau/Aβ42, diagnostic group, and change over time (baseline, 6-month, 12-month, and 24-month) on cognitive scores.RESULTSCSF p-tau/Aβ42 ratios predicted worsening cognitive impairment, both on global cognition and episodic memory in individuals with MCI and AD, but not in CU older adults and predicted decline in executive functioning for all three diagnostic groups.DISCUSSIONOur study, including CU, MCI, and AD individuals, provides evidence for differential cognitive consequences of accumulated AD pathology based on diagnostic groups.

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Efficacy of cognitive stimulation therapy for older adults with vascular dementia

Dementia & Neuropsychologia ◽

10.1590/1980-57642016dn11-040014 ◽

2017 ◽

Vol 11 (4) ◽

pp. 434-441 ◽

Cited By ~ 9

Author(s):

Federica Piras ◽

Elena Carbone ◽

Silvia Faggian ◽

Elisa Salvalaio ◽

Simona Gardini ◽

...

Keyword(s):

Quality Of Life ◽

Alzheimer’S Disease ◽

Older Adults ◽

Alzheimer's Disease ◽

Cognitive Functioning ◽

Vascular Dementia ◽

Cognitive Stimulation ◽

The Other ◽

Cognitive Stimulation Therapy

ABSTRACT. Background: Cognitive stimulation therapy (CST) is an evidence-based psychosocial intervention for people with mild-to-moderate dementia due to various etiological factors. Objective: The aim of the present study was to assess the efficacy of the CST program, Italian adaptation -CST-IT-, in individuals who have vascular dementia (VaD). Methods: Older adults with mild-to-moderate VaD (N = 35) were assigned to one of two programs: one group (N = 21) attended the 14 sessions of the CST-IT program, while the other, active control group (N = 14) took part in alternative activities. The following domains were examined: cognitive functioning, quality of life, mood, behavior, functional activities of daily living. Results: Compared with the active controls, the CST-IT group showed a greater improvement in general cognitive functioning after the intervention (i.e. score increase on the Mini-Mental State Examination and decrease on the Alzheimer's Disease Assessment Scale – Cognitive subscale). A trend towards improvement was also identified in short-term/working memory – the backward digit span task- and perceived quality of life (Quality of Life – Alzheimer's Disease scale). No significant differences emerged between the two groups for the other domains considered. Conclusion: The present results support the efficacy of CST in people with vascular dementia.

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Cognitive control constrains memory attributions

Behavioral and Brain Sciences ◽

10.1017/s0140525x19001869 ◽

2019 ◽

Vol 42 ◽

Author(s):

Colleen M. Kelley ◽

Larry L. Jacoby

Keyword(s):

Alzheimer’S Disease ◽

Older Adults ◽

Alzheimer's Disease ◽

Traumatic Brain Injury ◽

Brain Injury ◽

Cognitive Control

Abstract Cognitive control constrains retrieval processing and so restricts what comes to mind as input to the attribution system. We review evidence that older adults, patients with Alzheimer's disease, and people with traumatic brain injury exert less cognitive control during retrieval, and so are susceptible to memory misattributions in the form of dramatic levels of false remembering.

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Partner-Specific Communication Deficits in Individuals With Alzheimer's Disease

American Journal of Speech-Language Pathology ◽

10.1044/2020_ajslp-19-00094 ◽

2020 ◽

pp. 1-15

Author(s):

Eun Jin Paek ◽

Si On Yoon

Keyword(s):

Alzheimer’S Disease ◽

Older Adults ◽

Alzheimer's Disease ◽

Referential Communication ◽

Sorting Task ◽

Audience Design ◽

Healthy Older Adults ◽

Communication Task ◽

Design Skills ◽

Referential Expressions

Purpose Speakers adjust referential expressions to the listeners' knowledge while communicating, a phenomenon called “audience design.” While individuals with Alzheimer's disease (AD) show difficulties in discourse production, it is unclear whether they exhibit preserved partner-specific audience design. The current study examined if individuals with AD demonstrate partner-specific audience design skills. Method Ten adults with mild-to-moderate AD and 12 healthy older adults performed a referential communication task with two experimenters (E1 and E2). At first, E1 and participants completed an image-sorting task, allowing them to establish shared labels. Then, during testing, both experimenters were present in the room, and participants described images to either E1 or E2 (randomly alternating). Analyses focused on the number of words participants used to describe each image and whether they reused shared labels. Results During testing, participants in both groups produced shorter descriptions when describing familiar images versus new images, demonstrating their ability to learn novel knowledge. When they described familiar images, healthy older adults modified their expressions depending on the current partner's knowledge, producing shorter expressions and more established labels for the knowledgeable partner (E1) versus the naïve partner (E2), but individuals with AD were less likely to do so. Conclusions The current study revealed that both individuals with AD and the control participants were able to acquire novel knowledge, but individuals with AD tended not to flexibly adjust expressions depending on the partner's knowledge state. Conversational inefficiency and difficulties observed in AD may, in part, stem from disrupted audience design skills.

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