How does neurofeedback work?

We do not know for certain how or why neurofeedback (EEG biofeedback) training actually works, but we believe that neurofeedback is a learning tool which motivates the mind to guide the brain into various levels of relaxation at the neuronal, or cellular, level by targeting and training alpha frequencies (in ratio to other brain frequencies such as beta, theta and delta). It is believed that neurofeedback affects  the entire brain due to brain plasticity. It is assumed that various states of alpha relaxation at the neuronal level allow and even encourage the brain to eventually self regulate through possible changes in hormonal activity. It is assumed that once self regulation begins many physical symptoms are alleviated through a state of homeostasis, or balance, which eventually occurs.