Perhaps those older than I can answer this one for me. I used to think that the physical senses such as taste and smell got weaker with age, as often do sight and hearing. I noticed over a year or so ago that I had a heightened sense of taste. Things have more vibrant taste than ever before. It was odd, but noticeable. One day it really dawned on me when foods that I was used to suddenly tasted better than before, or at least had more taste. I know that is an inadequate way of describing it, but I can't really think of another way of putting it. Perhaps that some things were more exquisite than ever before is one way.
I have also been noticing that I have a heightened sense of smell lately. Some things are more pungeant than before. Things that never used to cause a gag reflex have literally done so in the last month or more. Just this morning, I experienced an overwhelming smell that I have smelled thousands of times before. This morning it was almost overpowering and I would have gagged if I didn't leave that room.
I don't know if this is normal or not, but I will try to look up some information on this.