San Diego State University, USA.
Brain Res. 2012 Mar 9;1442:55-65. doi: 10.1016/j.brainres.2011.12.030. Epub 2011 Dec 20.
Alzheimer's disease (AD) is a progressive, neurodegenerative disorder that impairs memory and semantic processing. AD patients and MCI patients at risk for AD show altered N400 ERP responses to incongruent visual and verbal stimuli. AD patients exhibit neuropathology in olfactory brain areas before cognitive symptoms, suggesting the potential for olfactory processing to reflect early pathology. Despite this, odor congruency has not been examined. We investigated odor-image congruency in older adults at genetic risk for AD. ApoE ε4 carriers and non-carriers were screened for anosmia, severe hyposmia, and dementia. Olfactory ERPs were measured 600-1300 ms following odor-image pairs. Odors were each presented once congruently and once incongruently via an olfactometer. Pz amplitude significantly decreased on incongruent trials in e4 carriers. Pz amplitude differences on congruous and incongruous trials were larger in non carriers. Regression indicated that congruency showed very high sensitivity and specificity for correctly classifying ε4 carriers from non-carriers.
阿尔茨海默病（AD）是一种进行性神经退行性疾病，会损害记忆和语义处理能力。AD 患者和有 AD 风险的 MCI 患者对不一致的视觉和言语刺激的 N400 ERP 反应发生改变。AD 患者在出现认知症状之前就已经出现了嗅觉脑区的神经病理学改变，这表明嗅觉处理可能反映了早期的病理变化。尽管如此，气味一致性尚未得到检验。我们研究了 AD 遗传风险的老年人群的气味-图像一致性。通过嗅觉计，对载脂蛋白 E4 携带者和非携带者进行了嗅觉缺失、严重嗅觉减退和痴呆症的筛查。在气味-图像对出现后 600-1300 毫秒测量嗅觉 ERP。每种气味分别通过嗅觉计一致和不一致地呈现一次。在 e4 携带者中，在不一致的试验中 Pz 振幅显著降低。非携带者在一致和不一致的试验中 Pz 振幅差异更大。回归表明，一致性对正确分类 e4 携带者和非携带者具有非常高的敏感性和特异性。
