Second, although the present study found that H2S attenuated post-SAH cognitive impairment, probably by ameliorating neuroinflammation, and identified microglial activation and enhanced TNF-α expression as the potential mechanisms by which inflammation affects cognitive function, the relationships between neuroinflammation and other factors, such as glutamate and NMDA receptors, were not explored. Here, TNF is linked to Cognitive impairment.