Effects of Gender and Apolipoprotein E on Novelty MMN and P3a in Healthy Elderly and Amnestic Mild Cognitive Impairment

Abstract

Background: The apolipoprotein E epsilon4 (ApoE ε4) allele and female gender may be important risk factors for the development of Alzheimer’s disease and amnestic mild cognitive impairment (aMCI). Novelty mismatch negativity (MMN) represents the pre-attentive index of deviance detection and P3a represents the attention orienting response. Furthermore, MMN and P3a components have been reported to be potential markers in aMCI. Therefore, this study will investigate the effects of gender and ApoE on auditory novelty MMN and P3a and their relationship to neuropsychological performance in aMCI.Methods: Thirty nine aMCI subjects and 44 controls underwent neuropsychological assessment and ApoE genotyping. Novelty MMN and P3a components were investigated during an auditory novelty oddball task.Results: Firstly, novelty MMN latency was significantly shorter in aMCI than in healthy control (HC) group. Secondly, novelty MMN latency was negatively correlated with episodic memory in aMCI, but not in HC. Novelty P3a latency was negatively correlated with information processing speed in all subjects. For gender effect, novelty MMN latency was shorter in aMCI females than in HC females. Moreover, novelty P3a amplitudes were lower in males than in females in both aMCI and HC. For the effect of ApoE status, novelty MMN latency was shorter in aMCI ApoE ε4- than HC ApoE ε4-.Conclusion: aMCI presents altered pre-attentive processing indexed by novelty MMN components. Furthermore, there may be a compensatory mechanism on the impaired processing in aMCI. It further suggests that aMCI female and ApoE ε4- recruited the compensatory mechanism.

Distinct Disruptive Patterns of Default Mode Subnetwork Connectivity Across the Spectrum of Preclinical Alzheimer’s Disease

“…All participants underwent comprehensive and standard neurocognitive assessments to evaluate their cognitive function, including general cognitive functions, episodic memory, executive function, information processing speed, and visual spatial domains (Gu et al, 2017; Gao et al, 2018). These assessments include the MMSE, the ADL, the MDRS-2, the MoCA, the SCD-Q, the CDR, the Hachinski Ischemic Scale (HIS), the HAMD, the Auditory Verbal Learning Test (AVLT; including the AVLT-immediate, the AVLT-5 min delay, and the AVLT-20 min delay), the Rey Complex Figure Test (CFT) delay, the Logical Memory Test (LMT), the CFT, the Clock-Drawing Test (CDT), the Boston Naming Test, the Category Verbal Fluency Test (including the CVFT-animals and the CVFT-objects), the Symbol Digit Modalities Test, the part A and B of the Trail Making Test (TMT), the Digit Span Test (including the DS forward and the DS backward), part A, B, and C of the Stroop Test, and the Semantic Similarity Test.…”

“…It is worth mentioning that, we grouped the neuropsychological tests into four cognitive domains (Gu et al, 2017; Gao et al, 2018). Episodic memory data were mainly derived from AVLT-20-min DR, LMT-20-min DR, and CFT-20-min DR.…”

A Systematic Review of Altered P300 Event-Related Potential in Apolipoprotein E4 (APOE4) Carriers

“…All 14 articles included were cross-sectional investigations. 14-27 Studies were conducted in 5 different countries: the United States (n = 7 studies), 16-18,20,21,23,27 Norway (n = 3 studies), 19,24,25 China (n = 2 studies), 15,26 Brazil (n = 1 study), 14 and Taiwan (n = 1 study). 22…”

“…Concerning the sample characteristics, the studies included information from a total of 773 participants (ranging from 21-75 years old), of which 295 were APOE4 carriers. Out of 14 studies, 12 included older people, 14-16,18-25,27 one included older people with mild cognitive impairment (MCI), 14,15 and another included AD patients. 14 Yu et al 26 and Corby et al 17 were the only ones that considered young and middle-aged individuals.…”

“…Concerning the APOE genotyping method, most of the studies adopted the polymerase chain reaction (PCR) method, using blood samples (n = 8 studies). 14,15,19,21,22,24,26,27 Three other studies obtained genotyping by buccal epithelial cells, using validated kits. However, they did not offer more specific details regarding the methodology applied.…”