I recently had a brain MRI in an attempt to diagnose the cause for some strange sensations and sounds in my head. The sound was like that made by clicking rocks together while swimming underwater. The MRI showed nothing amiss other than mild hardening of the blood vessels. (I m 76) Through an accidental process of elimination, I now suspect the culprit to be aspartame. In my search for an answer, I found that the sweeteners used in Sunny D aren t natural sugar and at least two of them contain aspartame. I quit drinking Sunny D and in a couple of days the problems went away. Is it just a coincidence, a lull in my symptoms, or was aspartame causing the problems?