I tried one of the Racetams about 8 months ago. It basically just dramatically sped up my metabolism and I zoomed for about 4 hours while eating everything in sight, then when it wore off I crashed and was exhausted the rest of the day. (I don't even have a BI, just a couple of very old, very mild concussions, only sequelae being tinnitus.) I decided NOT to give it to my sTBI son, it would have made his impulsitivity quite impossible to deal with. But for someone who needs to get a lot of stuff done quick and willing to take it a couple times a day then suffer the fatigue later, it could work. Cognitively I guess it helped a little. Everybody is different in that regard I suppose.