scholarly journals Relationship of Contextual Cueing and Hippocampal Volume in Amnestic Mild Cognitive Impairment Patients and Cognitively Normal Older Adults

2015 ◽  
Vol 21 (4) ◽  
pp. 285-296 ◽  
Author(s):  
Selam Negash ◽  
Daria Kliot ◽  
Darlene V. Howard ◽  
James H. Howard ◽  
Sandhistu R. Das ◽  
...  

AbstractThere is currently some debate as to whether hippocampus mediates contextual cueing. In the present study, we examined contextual cueing in patients diagnosed with mild cognitive impairment (MCI) and healthy older adults, with the main goal of investigating the role of hippocampus in this form of learning. Amnestic MCI (aMCI) patients and healthy controls completed the contextual cueing task, in which they were asked to search for a target (a horizontal T) in an array of distractors (rotated L’s). Unbeknownst to them, the spatial arrangement of elements on some displays was repeated thus making the configuration a contextual cue to the location of the target. In contrast, the configuration for novel displays was generated randomly on each trial. The difference in response times between repeated and novel configurations served as a measure of contextual learning. aMCI patients, as a group, were able to learn spatial contextual cues as well as healthy older adults. However, better learning on this task was associated with higher hippocampal volume, particularly in right hemisphere. Furthermore, contextual cueing performance was significantly associated with hippocampal volume, even after controlling for age and MCI status. These findings support the role of the hippocampus in learning of spatial contexts, and also suggest that the contextual cueing paradigm can be useful in detecting neuropathological changes associated with the hippocampus. (JINS, 2015, 21, 285–296)

Author(s):  
Liselotte De Wit ◽  
Vitoria Piai ◽  
Pilar Thangwaritorn ◽  
Brynn Johnson ◽  
Deirdre O’Shea ◽  
...  

AbstractThe literature on repetition priming in Alzheimer’s disease (AD) is inconsistent, with some findings supporting spared priming while others do not. Several factors may explain these inconsistencies, including AD severity (e.g., dementia vs. Mild Cognitive Impairment; MCI) and priming paradigm-related characteristics. This systematic review and meta-analysis provides a quantitative summary of repetition priming in AD. We examined the between-group standard mean difference comparing repetition priming in AD dementia or amnestic MCI (aMCI; presumably due to AD) to controls. Thirty-two studies were selected, including 590 individuals with AD dementia, 267 individuals with amnestic MCI, and 703 controls. Our results indicated that both individuals with aMCI and AD dementia perform worse on repetition priming tasks than cognitively older adults. Paradigm-related moderators suggested that the effect size between studies comparing the combined aMCI or AD dementia group to cognitively healthy older adults was the highest for paradigms that required participants to produce, rather than identify, primes during the test phase. Our results further suggested that priming in AD is impaired for both conceptual and perceptual priming tasks. Lastly, while our results suggested that priming in AD is impaired for priming tasks that require deep processing, we were unable to draw firm conclusions about whether priming is less impaired in aMCI or AD dementia for paradigms that require shallow processing.


2021 ◽  
pp. 1-11
Author(s):  
Kylie R. Kadey ◽  
John L. Woodard ◽  
Allison C. Moll ◽  
Kristy A. Nielson ◽  
J. Carson Smith ◽  
...  

Background: Body mass index (BMI) has been identified as an important modifiable lifestyle risk factor for dementia, but less is known about how BMI might interact with Apolipoprotein E ɛ4 (APOE ɛ4) carrier status to predict conversion to mild cognitive impairment (MCI) and dementia. Objective: The aim of this study was to investigate the interaction between APOE ɛ4 status and baseline (bBMI) and five-year BMI change (ΔBMI) on conversion to MCI or dementia in initially cognitively healthy older adults. Methods: The associations between bBMI, ΔBMI, APOE ɛ4 status, and conversion to MCI or dementia were investigated among 1,289 cognitively healthy elders from the National Alzheimer’s Coordinating Center (NACC) database. Results: After five years, significantly more carriers (30.6%) converted to MCI or dementia than noncarriers (17.6%), p <  0.001, OR = 2.06. Neither bBMI (OR = 0.99, 95%CI = 0.96–1.02) nor the bBMI by APOE interaction (OR = 1.02, 95%CI = 0.96–1.08) predicted conversion. Although ΔBMI also did not significantly predict conversion (OR = 0.90, 95%CI = 0.78–1.04), the interaction between ΔBMI and carrier status was significant (OR = 0.72, 95%CI = 0.53–0.98). For carriers only, each one-unit decline in BMI over five years was associated with a 27%increase in the odds of conversion (OR = 0.73, 95%CI = 0.57–0.94). Conclusion: A decline in BMI over five years, but not bBMI, was strongly associated with conversion to MCI or dementia only for APOE ɛ4 carriers. Interventions and behaviors aimed at maintaining body mass may be important for long term cognitive health in older adults at genetic risk for AD.


Author(s):  
Alexandre Chauvin ◽  
Shari Baum ◽  
Natalie A. Phillips

Purpose Speech perception in noise becomes difficult with age but can be facilitated by audiovisual (AV) speech cues and sentence context in healthy older adults. However, individuals with Alzheimer's disease (AD) may present with deficits in AV integration, potentially limiting the extent to which they can benefit from AV cues. This study investigated the benefit of these cues in individuals with mild cognitive impairment (MCI), individuals with AD, and healthy older adult controls. Method This study compared auditory-only and AV speech perception of sentences presented in noise. These sentences had one of two levels of context: high (e.g., “Stir your coffee with a spoon”) and low (e.g., “Bob didn't think about the spoon”). Fourteen older controls ( M age = 72.71 years, SD = 9.39), 13 individuals with MCI ( M age = 79.92 years, SD = 5.52), and nine individuals with probable Alzheimer's-type dementia ( M age = 79.38 years, SD = 3.40) completed the speech perception task and were asked to repeat the terminal word of each sentence. Results All three groups benefited (i.e., identified more terminal words) from AV and sentence context. Individuals with MCI showed a smaller AV benefit compared to controls in low-context conditions, suggesting difficulties with AV integration. Individuals with AD showed a smaller benefit in high-context conditions compared to controls, indicating difficulties with AV integration and context use in AD. Conclusions Individuals with MCI and individuals with AD do benefit from AV speech and semantic context during speech perception in noise (albeit to a lower extent than healthy older adults). This suggests that engaging in face-to-face communication and providing ample context will likely foster more effective communication between patients and caregivers, professionals, and loved ones.


2021 ◽  
Vol 73 (12) ◽  
pp. 786-792
Author(s):  
Doonyaporn Wongsawaeng ◽  
Orasa Chawalparit ◽  
Siriwan Piyapittayanan ◽  
Tanyaluck Thientunyakit ◽  
Weerasak Muangpaisan ◽  
...  

Objective: Depression among older adults is frequently an early symptom of cognitive decline, and is believed to be a risk factor for Alzheimer’s disease (AD). Hippocampal subfield volume loss is found in both mild cognitive impairment (MCI) and major depressive disorder (MDD). We aimed to investigate the potential of MR hippocampal subfield volumetry for discriminating among healthy older adults (HOA) and older adults with MCI or MDD. Materials and Methods: Seventy age-matched subjects (29 non-depressed MCI, 12 MDD, and 29 HOA) underwent 3-Tesla MR imaging (MRI) with high-resolution 3D-T1W-TFE whole brain. Hippocampal subfield volumetric measurements were performed using FreeSurfer software to distinguish among MCI, MDD, and HOA. Subgroup analysis with amyloid PET result was also performed.Results: Significantly smaller bilateral hippocampal tail volume was observed in MCI compared to HOA (p=0.004 and p=0.04 on the left and right side, respectively). The same comparative finding was observed at left HATA (hippocampus-amygdala-transition-area) of MCI (p=0.046). Other regions showed non-significantly smaller size in MCI than in HOA [left molecular layer HP (p=0.06), left whole hippocampus (p=0.06), and left CA1 (p=0.07)]. There was a non-significant trend toward smaller size in almost all 13 subfield hippocampal regions of MCI compared to MDD, even in subgroup analysis with amyloid PET result.Conclusion: MR hippocampal subfield volumetry may have value in routine clinical practice for screening individuals with MCI, and may be a valuable adjunct to amyloid PET study for very early-stage diagnosis of AD.


2020 ◽  
Vol 78 (1) ◽  
pp. 405-412
Author(s):  
Stelios Zygouris ◽  
Paraskevi Iliadou ◽  
Eftychia Lazarou ◽  
Dimitrios Giakoumis ◽  
Konstantinos Votis ◽  
...  

Background: Literature supports the use of serious games and virtual environments to assess cognitive functions and detect cognitive decline. This promising assessment method, however, has not yet been translated into self-administered screening instruments for pre-clinical dementia. Objective: The aim of this study is to assess the performance of a novel self-administered serious game-based test, namely the Virtual Supermarket Test (VST), in detecting mild cognitive impairment (MCI) in a sample of older adults with subjective memory complaints (SMC), in comparison with two well-established screening instruments, the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE). Methods: Two groups, one of healthy older adults with SMC (N = 48) and one of MCI patients (N = 47) were recruited from day centers for cognitive disorders and administered the VST, the MoCA, the MMSE, and an extended pencil and paper neuropsychological test battery. Results: The VST displayed a correct classification rate (CCR) of 81.91% when differentiating between MCI patients and older adults with SMC, while the MoCA displayed of CCR of 72.04% and the MMSE displayed a CCR of 64.89%. Conclusion: The three instruments assessed in this study displayed significantly different performances in differentiating between healthy older adults with SMC and MCI patients. The VST displayed a good CCR, while the MoCA displayed an average CCR and the MMSE displayed a poor CCR. The VST appears to be a robust tool for detecting MCI in a population of older adults with SMC.


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