Contingency awareness is thought to rely on an intact medial temporal lobe and also appears to be a function of age, as older subjects tend to be less aware. The current investigation used functional magnetic resonance imaging, transcranial direct current stimulation, and eyeblink classical conditioning to study brain processes related to contingency awareness as a function of age. Older adults were significantly less aware of the relationship between the tone-airpuff pairings than younger adults. Greater right parietal functional magnetic resonance imaging activation was associated with higher levels of contingency awareness for younger and older subjects. Cathodal transcranial direct current stimulation over the right parietal lobe led to lower levels of awareness in younger subjects without disrupting conditioned responses. Older adults exhibited hyperactivations in the parietal and medial temporal lobes, despite showing no conditioning deficits. These findings strongly support the idea that the parietal cortex serves as a substrate for contingency awareness and that age-related disruption of this region is sufficient to impair awareness, which may be a manifestation of some form of naturally occurring age-related neglect.

中文翻译：

---

应急意识、衰老和顶叶

应急意识被认为依赖于完整的内侧颞叶，并且似乎也是年龄的函数，因为年龄较大的受试者往往意识较差。目前的研究使用功能性磁共振成像、经颅直流电刺激和眨眼经典条件反射来研究与作为年龄函数的应急意识相关的大脑过程。与年轻人相比，老年人明显不太了解音调-气吹配对之间的关​​系。更大的右顶叶功能磁共振成像激活与年轻和年长受试者更高水平的应急意识相关。右侧顶叶的阴极经颅直流电刺激导致年轻受试者的意识水平降低，而不会破坏条件反应。尽管没有表现出调节缺陷，但老年人的顶叶和内侧颞叶表现出过度激活。这些发现有力地支持了这样一种观点，即顶叶皮层是应急意识的基础，并且该区域与年龄相关的破坏足以损害意识，这可能是某种形式的自然发生的与年龄相关的忽视的表现。