The cat is finally out of the bag! I have been diagnosed as being hypothyroid today with my TSH currently at 13. No wonder even after excessive b12 supplementation, my symptoms were refusing to improve. I know it's still a long journey for getting my memory/cognitive issues fixed but at least I m hopeful now. The doc has put me on synthroid 88mcg. Thanks everyone for listening patiently and providing expert advice when I needed it the most. For all those who r not noticing any improvement with b12 supplementation, please get your tsh along with your free t3 And t4 levels checked. It's really difficult to pinpoint either one as most of the symptoms overlap. I was confused, spaced out and having memory recall issues. Is there anybody here who has both - b12 def, hypothyroidism? How can you manage both of them simultaneously?