TNF and neurodegenerative disease: Evidence is accumulated to support the involvement of neuroinflammation in neurodegenerative diseases, including Alzheimer's and Parkinson's diseases.51, 52, 53 TNF‐α is a potent pro‐inflammation cytokine13 and plays an important role in neuroinflammation.47 To determine the effect of repeated TNF‐α challenge on learning, cognition, and memory, the spatial learning and memory ability were examined in mice challenged with TNF‐α or control vehicle by using the Morris water maze and the novel object recognition (NOR) models.