In this study, we observed that both long (6 months)‐ and short (1 month)‐term AAV‐GFAP‐Hevin treatments provided beneficial effects in age‐associated cognitive decline, sustaining that this molecule has the potential to positively impact aging synapses in different time windows even when age‐associated detrimental processes have already begun. The gene discussed is GFAP; the disease is Mental deterioration.