Using Voxel-Based Morphometry to Examine the Relationship between Regional Brain Volumes and Memory Performance in Amnestic Mild Cognitive Impairment

Background: Structural brain magnetic resonance imaging (MRI) scans may provide reliable neuroimaging markers for defining amnestic mild cognitive impairment (aMCI). Objective: We sought to characterize global and regional brain structures of aMCI among rural-dwelling older adults with limited education in China. Methods: This population-based study included 180 participants (aged≥65 years, 42 with aMCI and 138 normal controls) in the Shandong Yanggu Study of Aging and Dementia during 2014–2016. We defined aMCI following the Petersen’s criteria. Global and regional brain volumes were automatically segmented on MRI scans and compared using a region-of-interest approach. Data were analyzed using general linear regression models. Results: Multi-adjusted β-coefficient (95% confidence interval) of brain volumes (cm3) associated with aMCI was –12.07 (–21.49, –2.64) for global grey matter (GM), –18.31 (–28.45, –8.17) for global white matter (WM), 28.17 (12.83, 44.07) for cerebrospinal fluid (CSF), and 2.20 (0.24, 4.16) for white matter hyperintensities (WMH). Furthermore, aMCI was significantly associated with lower GM volumes in bilateral superior temporal gyri, thalamus and right cuneus, and lower WM volumes in lateral areas extending from the frontal to the parietal, temporal, and occipital lobes, as well as right hippocampus (p < 0.05). Conclusion: Brain structure of older adults with aMCI is characterized by reduced global GM and WM volumes, enlarged CSF volume, increased WMH burden, reduced GM volumes in bilateral superior temporal gyri, thalamus, and right cuneus, and widespread reductions of lateral WM volumes.

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Lower functional hippocampal redundancy in mild cognitive impairment

Translational Psychiatry ◽

10.1038/s41398-020-01166-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Stephanie Langella ◽

◽

Muhammad Usman Sadiq ◽

Peter J. Mucha ◽

Kelly S. Giovanello ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Cognitive Decline ◽

Resting State ◽

Memory Performance ◽

Potential Mechanism ◽

Network Efficiency ◽

Cognitively Normal ◽

Normal Individuals ◽

The Relationship

AbstractWith an increasing prevalence of mild cognitive impairment (MCI) and Alzheimer’s disease (AD) in response to an aging population, it is critical to identify and understand neuroprotective mechanisms against cognitive decline. One potential mechanism is redundancy: the existence of duplicate elements within a system that provide alternative functionality in case of failure. As the hippocampus is one of the earliest sites affected by AD pathology, we hypothesized that functional hippocampal redundancy is protective against cognitive decline. We compared hippocampal functional redundancy derived from resting-state functional MRI networks in cognitively normal older adults, with individuals with early and late MCI, as well as the relationship between redundancy and cognition. Posterior hippocampal redundancy was reduced between cognitively normal and MCI groups, plateauing across early and late MCI. Higher hippocampal redundancy was related to better memory performance only for cognitively normal individuals. Critically, functional hippocampal redundancy did not come at the expense of network efficiency. Our results provide support that hippocampal redundancy protects against cognitive decline in aging.

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Comparing the relationship between subjective memory complaints, objective memory performance, and medial temporal lobe volumes in patients with mild cognitive impairment

Alzheimer s & Dementia Diagnosis Assessment & Disease Monitoring ◽

10.1016/j.dadm.2015.03.002 ◽

2015 ◽

Vol 1 (2) ◽

pp. 242-248 ◽

Cited By ~ 9

Author(s):

Courtney A. Fyock ◽

Benjamin M. Hampstead

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Memory Performance ◽

Subjective Memory Complaints ◽

Subjective Memory ◽

Memory Complaints ◽

The Relationship

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Sex differences in cortisol and memory following acute social stress in amnestic mild cognitive impairment

10.1101/757484 ◽

2019 ◽

Cited By ~ 1

Author(s):

Kelly J. Murphy ◽

Travis E. Hodges ◽

Paul A.S. Sheppard ◽

Angela K. Troyer ◽

Elizabeth Hampson ◽

...

Keyword(s):

Working Memory ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Episodic Memory ◽

Social Stress ◽

Spatial Working Memory ◽

Memory Function ◽

Amnestic Mild Cognitive Impairment ◽

Amci Group ◽

The Relationship

AbstractObjectiveOlder adults with amnestic mild cognitive impairment (aMCI) develop Alzheimer’s type dementia approximately ten times faster annually than the normal population. Adrenal hormones are associated with aging and cognition. We investigated the relationship between acute stress, cortisol, and memory function in aMCI with an exploratory analysis of sex.MethodSalivary cortisol was sampled diurnally and during two test sessions, one session with the Trier Social Stress Test (TSST), to explore differences in the relationship between cortisol and memory function in age-normal cognition (NA) and aMCI. Participants with aMCI (n=6 women, 9 men; mean age=75) or similarly aged NA (n=9 women, 7 men, mean age=75) were given tests of episodic, associative, and spatial working memory with a psychosocial stressor (TSST) in the second session.ResultsThe aMCI group performed worse on the memory tests than NA as expected, and males with aMCI had elevated cortisol levels on test days. Immediate episodic memory was enhanced by social stress in NA but not in the aMCI group, indicating that stress-induced alterations in memory are different in individuals with aMCI. High cortisol was associated with impaired performance on episodic memory in aMCI males only. Cortisol in Session 1 moderated the relationship with spatial working memory, whereby higher cortisol was associated with worse performance in NA, but better spatial working memory in aMCI. In addition, effects of aMCI on perceived anxiety in response to stress exposure were moderated by stress-induced cortisol in a sex-specific manner.ConclusionsWe show effects of aMCI on Test Session cortisol levels and effects on perceived anxiety, and stress-induced impairments in memory in males with aMCI in our exploratory sample. Future studies should explore sex as a biological variable as our findings suggests that effects at the confluence of aMCI and stress can be obfuscated without sex as a consideration.

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The reduced left hippocampal volume related to the delayed P300 latency in amnestic mild cognitive impairment

Psychological Medicine ◽

10.1017/s0033291720000811 ◽

2020 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Lijuan Gao ◽

Lihua Gu ◽

Hao Shu ◽

Jiu Chen ◽

Jianli Zhu ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Hippocampal Volume ◽

Amnestic Mild Cognitive Impairment ◽

Parahippocampal Gyrus ◽

Structural Basis ◽

P300 Latency ◽

Information Processing Speed ◽

Amci Group ◽

The Relationship

Abstract Background Amnestic mild cognitive impairment (aMCI) is characterized by delayed P300 latency and reduced grey matter (GM) volume, respectively. The relationship between the features in aMCI is unclear. This study was to investigate the relationship between the altered P300 latency and the GM volume in aMCI. Methods Thirty-four aMCI and 34 well-matched normal controls (NC) were studied using electroencephalogram during a visual oddball task and scanned with MRI. Both tests were finished in the same day. Results As compared with the NC group, the aMCI group exhibited delayed P300 latency in parietal cortex and reduced GM volumes in bilateral temporal pole and left hippocampus/parahippocampal gyrus. A remarkable negative correlation was found between delayed P300 latency and reduced left hippocampal volume only in the aMCI group. Interestingly, the mediating analysis found P300 latency significantly mediated the association between right supramarginal gyrus volume and information processing speed indicated by Stroop Color and Word Test A scores. Conclusions The association between delayed P300 latency and reduced left hippocampal volume in aMCI subjects suggests that reduced left hippocampal volume may be the potential structural basis of delayed P300 latency.

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