Recent studies have found that general anesthetic drugs are neurotoxic to developing neurons, causing learning and memory deficits and behavioral abnormalities. Ketamine is a commonly used general anesthetic drug in pediatric patients. A retrospective clinical study found that children who had undergone prolonged surgery before the age of 3 years, or who had used ketamine several times for surgical purposes, showed learning and memory deficits and behavioral abnormalities during school age. A study on “Ketamine induces tau hyperphosphorylation at serine 404 in the hippocampus of neonatal rats” published in Neural Regeneration Research in China (English version), June 17, 2013. A study on “Ketamine induces tau protein phosphorylation and neuronal toxicity in developing neurons”, applying molecular biology techniques at the genetic and protein levels. The results demonstrated that ketamine can cause disorder of microtubule arrangement in neonatal rat hippocampal neurons, can increase the expression of abnormally phosphorylated tau protein mRNA in neonatal rat hippocampus, and induce tau protein hyperphosphorylation site in S404 but not in S396 in neonatal rat hippocampus. the authors concluded that ketamine may cause tau protein phosphorylation through tau protein Ser404 site hyperphosphorylation, and tau protein hyperphosphorylation neurotoxicity in neonatal mice by leading to disruption of microtubule structure and impairment of axonal transport, ultimately leading to neuronal cell death. The experimental results suggest that ketamine, a widely used pediatric general anesthetic, may be a risk factor for affecting learning ability in children.