Why does chocolate make us use our brain more?

Answer 1

Whether it actually makes you use your brain more is an open question. Chocolate does have a certain amount of caffeine in it, however the amount of Caffeine in Chocolate is very little - about 5 to 10 milligrams of caffeine in one ounce of bittersweet chocolate, 5 milligrams in milk chocolate, and 10 milligrams in a six-ounce cup of cocoa. Compare this to 100-150 milligrams found in a cup of coffee.
It also contains Theobromine, which helps boost low blood-sugar levels and another chemical, Chromium, helps to control blood sugar. Theobromine, however, is highly toxic to dogs, cats, and other household pets. It overstimulates their cardiac and nervous systems, and can cause instant death.
For humans though, Chocolate is a wonderful energy source (it is digested quite quickly, and tends to raise human's blood sugar. Since the brain works best on sugar (better than on complex carbohydrates or protein), there may be some connection there...

Answer 2

caffeine affected to your brain tissues