Visual cortex in aging and Alzheimer's disease: changes in visual field maps and population receptive fields.
Visual cortex in aging and Alzheimer's disease: changes in visual field maps and population receptive fields.
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DOI：
10.3389/fpsyg.2014.00074
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发表时间：
2014
影响因子：
3.8
通讯作者：
Barton B
中科院分区：
文献类型：
--
作者：
Brewer AA;Barton B
尽管几项研究表明，大脑皮质的改变是导致视力下降等与年龄相关的视觉缺陷的原因，但人们对健康衰老过程中视觉皮质实际发生的变化知之甚少。最近的两项研究表明，初级视皮层(V1)在正常衰老过程中发生了变化；然而，还没有研究表征衰老对V1以外的视皮层的影响，这是理解衰老过程和与年龄相关疾病的变化相比较的重要指标。同样，几乎没有关于阿尔茨海默病(AD)视觉皮质变化的信息，AD是最常见的痴呆症形式。由于视觉缺陷通常被报道为AD的首发症状之一，因此对AD患者视皮层的这种变化的测量可能有助于我们了解神经退行性变对视觉系统的影响，并有助于AD的早期发现、准确诊断和及时治疗。在这里，我们首先使用功能磁共振成像来比较年轻人和健康老年受试者的枕部V1、V2、V3和hV4的视野图(VFM)组织和群体接受野(RFs)。健康的老年受试者并不表现出主要的VFM组织缺陷，但与健康的年轻对照组相比，V1、V2和hV4的中央凹的表面积减少和PRF大小增加。这些测量结果与健康衰老中出现的行为缺陷是一致的。然后，我们在两名轻度AD患者中证明了这些测量的可行性和第一个特征，这些测量揭示了作为AD病理生理学的一部分，视觉皮质的潜在变化。我们的数据有助于我们理解正常衰老过程中视觉加工通路的变化，并为进一步研究更早、更明确地检测AD提供基础。
Although several studies have suggested that cortical alterations underlie such age-related visual deficits as decreased acuity, little is known about what changes actually occur in visual cortex during healthy aging. Two recent studies showed changes in primary visual cortex (V1) during normal aging; however, no studies have characterized the effects of aging on visual cortex beyond V1, important measurements both for understanding the aging process and for comparison to changes in age-related diseases. Similarly, there is almost no information about changes in visual cortex in Alzheimer's disease (AD), the most common form of dementia. Because visual deficits are often reported as one of the first symptoms of AD, measurements of such changes in the visual cortex of AD patients might improve our understanding of how the visual system is affected by neurodegeneration as well as aid early detection, accurate diagnosis and timely treatment of AD. Here we use fMRI to first compare the visual field map (VFM) organization and population receptive fields (pRFs) between young adults and healthy aging subjects for occipital VFMs V1, V2, V3, and hV4. Healthy aging subjects do not show major VFM organizational deficits, but do have reduced surface area and increased pRF sizes in the foveal representations of V1, V2, and hV4 relative to healthy young control subjects. These measurements are consistent with behavioral deficits seen in healthy aging. We then demonstrate the feasibility and first characterization of these measurements in two patients with mild AD, which reveal potential changes in visual cortex as part of the pathophysiology of AD. Our data aid in our understanding of the changes in the visual processing pathways in normal aging and provide the foundation for future research into earlier and more definitive detection of AD.
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影响因子：
14.5
作者：
Bokde, ALW;Lopez-Bayo, P;Hampel, H
通讯作者：
Hampel, H
影响因子：
3.7
作者：
Engel, SA;Glover, GH;Wandell, BA
通讯作者：
Wandell, BA
影响因子：
2.5
作者：
Black, SE
通讯作者：
Black, SE
影响因子：
5.7
作者：
D'Esposito, M;Zarahn, E;Rypma, B
通讯作者：
Rypma, B
影响因子：
25
作者：
Baseler, Heidi A.;Gouws, Andre;Morland, Antony B.
通讯作者：
Morland, Antony B.