Gate Control Theory of Pain
The gate control theory is the basis for the design of Buzzy®. The premise is that when nerves receive non-painful signals such as vibration or cold, the brain closes the gate on pain signals. For example, if you hit your finger with a hammer, you might instinctively begin to rub it, shake it, or run it under cold water. You are sending non-pain signals through your nerves to close the gate on the pain signals.
Descending Inhibitory Controls
The second part of Buzzy efficacy, and the reason it can help even when distant from the site of procedural pain, is something called Descending Noxious Inhibitory Control, or DNIC. While gate control happens locally (confusing nerves right where the pain happens) another effective mechanism of pain control uses the brain’s ability to dampen out unwanted signals. Instead of happening right where the nerves are, though, an intense degree of cold can work anywhere on the body.
The idea is like putting your hand in a bucket of ice water. Whoa, it’s cold! But you can handle the amount of cold initially. Studies have found that when someone’s hand is in ice water, they can handle more intense pain everywhere else in the body, probably because the sensation of ice is so intense it doesn’t leave as much room for the brain to notice pain as sharply other places.
It is as if when one sensation is very intense, the brain turns the volume down on sensations anywhere in the body.
In scientific terms, intense cold activates a supraspinal modulation raising the body’s overall pain threshold.