Neurofeedback is commonly provided using video or sound, with positive feedback for desired brain activity and negative feedback for brain activity that is undesirable. Training the brain is based on the individual client’s brainwave pattern compared to an international database of thousands of brain scans. Brain waves are electrical impulses that fire as your brain cells communicate with each other. Brainwaves convey a great deal about your overall brain function. Training is also based on client response. The subtle feedback based training method is designed to change the brain over time. NF has been used with a variety of individuals with issues such as PTSD, trauma, and substance use with promising results.