In the present study, we mainly investigated that PBMT treatment of lymph nodes can exert beneficial neurogenesis modulating effects by regulating the function of non-parenchymal CD4+ T cells, induction of improvement of brain microenvironment and alleviation of cognitive deficits in APP/PS1 and 3xTg-AD mouse models. The gene discussed is PSEN1; the disease is Cognitive impairment.