Longans strengthen the heart spleen and calm the nerves. They are effective in treating insomnia, frailty,forgetfulness, dizziness and improve your overall health.8. Grapefruits are a rich source of Vitamins A, B1 and C which help to Brain Peak neutralize the acidic effects of food which are harmful to the nerve system. One feels refreshed and alert if consume regularly. Oranges and lemons achieve the same effects too. It's quite simple: if you want to begin strengthening your brain's power, you need to give it some exercise.OK. It's not a simple matter of going down to the gym and getting your brain to pump weights. But actually, the process of brainpower strengthening isn't too different from that model.