The first usable energy medicine device was developed by Dr. Reinhold Voll, MD. Dr. Voll and his colleagues discovered that the electrical conductivity of the skin increases dramatically at acupoints and that each acupoint has a specific conductivity value for healthy people. A lower than normal conductivity was found to indicate an inflammation or irritation in the organ corresponding to the acupoint being tested. Conversely, a higher conductivity meant a fatigued or degenerating organ. Dr. Voll's technique became known as "Electroacupuncture According to Voll" (EAV) and is the basis for all electroacupuncture biofeedback devices in use today. Dr. Voll also discovered that if a patient held vials containing homeopathic solutions of various disease-causing agents (bacteria, viruses, diseased tissue, etc.) then the acupoint conductivity reading would return to normal when the patient held a vial containing the agent corresponding to his/her disease (the homeopathic principle of like cures like). Dr. Voll's machine, the Dermatron, is used not only to establish specific diagnoses, but also to determine food allergies and the presence of chemical toxins. EAV testing is also used to determine the exact remedies required to correct any problems. Testing a significant number of the more than 2000 acupoints corresponding to specific parts of the internal organs is very time consuming and this has led to the development of faster machines.