I would reckon this is also partially due to the effect of aspirin on things like IL-6 and reduction of IBA1 aka AIF1. Plasticity is the natural state of the brain, barring metabolic dysregulation. Worth noting that AIF-1 is normally only present in inflammatory situations and controls blood vessel formation; therefore, reduced expression would indicate reduced inflammation and indicate reduced risk of atherosclerosis, vessel thickening, stroke, etc.