I have a machine that makes graphs kind of like that. Only you can pick posterior ot lateral results. It is in color and the high readings are the ones that show nerve interference, snd inflammation. The low readings are normal. this one probably measures something else. I bought all the 'toys" when I began practicing. But I discovered I could get any result I wanted, it wasn't objective. You can alter pressure from one side to another as you go down the spine and the computer takes its reading when the pressure applicator clicks. it is pretty accurate though and is good patient education. --Marjorie