Biofeedback is a term that covers all different training methods based on the biological feedback. However, here we describe EEG and HEG as different category (as neurofeedback) and when we talk about biofeedback, we refer to the methods that measure and aim to change physiological parameters such as heart rate (HR), heart rate variability (HRV), peripheral skin temperature, sweet gland activity etc. Electrodes attached to the skin (or finger sensors) measure these processes and display them on a monitor. Usually the client is watching a video or a visual presentation that changes according to his/her current state.
The biofeedback system that I use includes a set of interesting games and screen visualizations that are very appealling to most children. They learn self-regulation skills while being engaged in favourite games and activities.