Final answer:
Dr. Norm Shealy is the researcher who sought non-pharmaceutical and non-invasive treatments for chronic pain after earning his M.D. and became known for his invention of the spinal cord stimulator for pain control.
Step-by-step explanation:
The researcher/author who became interested in non-pharmaceutical and non-invasive treatments for chronic illness/pain after receiving his M.D. in 1971 is Dr. Norm Shealy. Dr. Shealy is a pioneer in the field of pain management and the development of surgical and non-surgical techniques for alleviating chronic pain, encountering such challenges after his medical training.
One of his significant contributions to medicine is the invention of the spinal cord stimulator, which is used for pain control. His approach towards pain management emphasizes the need for treatments that do not solely rely on medication, thereby influencing the practice of holistic and integrative medicine.