Positive effects of creatine supplementation on memory in healthy individuals
ncbi.nlm.nih.gov
ncbi.nlm.nih.gov
Made in USA, except not really....
One exception may be Con-Cret, which may be producing creatine in Nebraska. But I'm not sure if they're NSF certified.
"Creatine supplementation for optimization of physical function in the patient at risk of functional disability: A systematic review and meta-analysis"
Of course, it remains unknown if natural dietary improvements could have a similar effect without the need to use a chemical supplement where the long-term effects aren't well studied.