How sensitive can human touch be?


During my career as a Physical Therapist, I have been learning how to touch in a more educated and refined way. One of the first rhythms I learned to feel was respiration: placing my hands on the rib cage to monitor the inhale and exhale, paying attention to the symmetry of the movement between the left and right side, the amount the movement in the upper, middle and lower lobes. Noticing the sensations created by the rattling of the mucus in the lungs. My hands feel all this information to understand the problem and helping me to decide my treatment plan. I learned how to move joints through their range of motion, pay attention to how smoothly they move, and how it feels when the joint could move no further. Sometimes the knee would not bend anymore because of what felt like a hard stop; other times it would feel like there was something mushier limiting the movement. We called it a “boggy end feel!”

Helping children with physical disabilities gain as much independent movement as possible educated my hands in a very specific way. For example, if a child with cerebral palsy was learning to roll from her back to her stomach, I would encourage her to turn her head, to bring her arm across her body, and then give the least amount of facilitation to the pelvis to help create the roll onto her stomach. That kind of touch to facilitate movement requires careful listening through the hands to feel for tension or engagement of the muscles needed to achieve the movement.


In the last twenty years, through my training in CranioSacral Therapy, I have been refining my ability to feel even more nuanced movement within the body. I've learned how to feel the movement that is created by the flow of the cerebral spinal fluid throughout the nervous system. A fascinating piece of research has carried by Thomas Rasmussen and Karl Meulengracht. They have recently published a paper called “Direct measurements of the rhythmic motions of the head identifies a third rhythm.”


Over a number of years, they created a piece of equipment that was able to measure small movements of the head. With this level of sensitivity to movement, they could measure the motion made by respiration, cardiac pulses, and a third rhythm that is thought to be the cranial-sacral impulse. This research paper is very well explained by Thomas Rasmussen in this video.


It is very exciting to see the research being published about this subtle type of movement that trained human hands can feel. My hands are continuing to learn about the art of healing touch 30 years later. This is one of the great joys of my work.