Herman - I see a functional chiropractor who practices Directional Non-Force Technique (DNFT)
TM for spinal alignment maintenance and she does a NeuroSpinal Function Index or Neural Efficiency Index that includes -- HRV, muscle tone and balance, organ and gland control -- by a scanning evaluation called COREScore
TM. My result report lists a website, www.subluxation.com. You might try investigating there to see if they have a list of practitioners in your area who use their scanning equipment.
Jackie