In my humble opinion I can say Mono-Sodium-Glutamat (Natrium Glutamat) can have inmediate effect in your brain... I have tinnitus for abut 5 years and If I eat msg I feel it in about 15 minutes... it makes a higher pitch in the constant noise I hear... this I tested a few times and I'm pretty sure no other food or edible substance has such an effect as MSG...