TNF‐α level is increased in Alzheimer's disease patients, and inhibition of TNF‐α is proposed to treat Alzheimer's disease.63 Sleep disruption interferes with the normal restorative functions of NREM and REM sleep and is associated with impairments in attention, memory and decision‐making.64 Our data indicate that chronically elevated TNF‐α and impaired hypocretin expression are likely involved in the development of impaired learning, memory and cognition. This evidence concerns the gene HCRT and Alzheimer disease.