高齡時代已經來臨，愈來愈多老年人會罹患阿茲海默症和認知功能失常，研究指出載運蛋白4（Apoliporotein ε , Apoɛ4）遺傳基因是罹患阿茲海默症的危險因子，Apoɛ 基因是遺傳基因中，位於人類第19 對染色體，它與體內膽固醇、三酸甘油脂運送有密切關係，常見Apoɛ 基因型態有ε2, ε3, ε4 三種異構物。由於遺傳基因可能帶來潛在的阿茲海默罹患率、大腦血氧濃度低下、認知功能不足、大腦海馬迴萎縮等；腦磁圖儀 (Magnetoencephalography, MEG) 是評估大腦磁場的高科技儀器，可以明確了解大腦深層各功能區塊的異常磁場，藉由MEG 等評估腦部活化區域及大腦執行控制功能的工具，許多研究發現適度的調整生活型態、提升身體活動量，可以延緩阿茲海默症的好發時機或降低疾病的影響。本篇文章整理近年來相關的文獻指出：1.帶有Apoɛ4 (Apoɛ4+)基因型態會影響中老年人，會降低腦部血流氧化能力而影響認知功能。2. Apoɛ4+ 基因之中老年阿茲海默患者，會伴隨較大量大腦海馬迴萎縮的程度。3.身體活動量可影響Apoɛ4 中老年人，包括：可有效改善反應時間、縮短M170 的潛伏時間、增加M170 振幅，提升大腦執行功能等。對大腦有更深的介紹認識。

As aging, the prevalence of Alzheimer's disease and cognition dysfunction increase in many countries. Studies showed that the Apolipoprotein Epsilon4 (Apo ε4 ) allele is a significant genetic risk factor for Alzheimer's disease (AD). The Apolipoprotein ε (Apo ε) gene is localized on chromosome 19 in a single locus with three alleles (ε2, ε3, and ε4) responsible for the three major Apo ε isoforms (Apo ε2, Apo ε3, and Apo ε4). The Apo ε4genotype results to morphological change of brain tissue and lead to reduction of cerebral oxygenation, impairment of cognition, and hippocampi volume atrophy. Magnetoencephalography (MEG) is a functional neuroimaging technique for mapping brain activity by recording magnetic fields produced by electrical currents occurring naturally in the brain. The M170 peak in MEG was identified as a potential marker for pre-clinical decline as ε4 carriers exhibited longer M170 latency, and lower M170 amplitude than healthy adults. This literature review showed that: 1. The cognitive function was impaired due to the low cerebral blood flow and oxygenation in middle and old age Apo ε4 carriers. 2. Middle and old age Apo ε4 carriers are often associated with higher degree of hippocampus atrophy. 3. The increase of physical activity level can shorten M170 latency, increase M170 amplitude and result to improvement of brain executive control function in Apo ε4 carriers.