The present study examined the effects of Tremella fuciformis (TF) on the learning and memory function and the neural activity in rats with TMT-induced memory deficits.The rats were administered saline or TF (TF 25, 50, 100mg/kg, p.o.) daily for 21 days.The cognitive improving efficacy of TF on the amnesic rats, which was induced by TMT, was investigated by assessing the Morris water maze test and by performing acetylchoine transferase (ChAT) and cAMP responsive element binding protein (CREB) immunohistochemistry.In order to confirm the underlying mechanisms of the memory enhancing effects of TF, we assessed the neurite outgrowth of PC12 cells.We also administered 18F-Fluorodeoxyglucose and performed a PET/CT scan of the frontal lobe.