Maximizing Your Three Brains for Optimal Performance.

The brain can be thought of as having three functional layers: the reptilian brain, the limbic system, and the cortex. These layers interact with each other, with the cortex being the most recently evolved and capable of regulating the emotional and regulatory functions of the other layers. Biofeedback techniques can be used to consciously regulate the autonomic functions of the reptilian brain, such as blood pressure and heart rate.