It is appears that within a certain range, the change of T3 level in early older stroke recovery patients with cognitive dysfunction and low thyroid hormone level is correlated with the change in the MoCA score, i.e., the cognitive function of patients will be improved together with the increase of T3 level, and the increase of T3 level will, in turn, improve the cognitive function of patients with cognitive dysfunction in stroke, and that the two function will boost each other and influence each other. The gene discussed is TG; the disease is stroke disorder.