When neurons in the brain are using more lactate, they're releasing a variety of neurotransmitters. They release more norepinephrine, for example, to help the brain working better to have more focus and attention. It also signals to the brain to make more brain-derived neurotrophic factor (BDNF) ... BDNF is the youth elixir for the brain, and exercising muscles produce lactate to help you bathe your brain in it.