Scientists have discovered a new pain center in the brain that can "disconnect" to relieve the agony of chronic nervous sensitivity.
Nervous pain is one of the most difficult types of constant discomfort to treat, since most analgesics do not target the right receptors for it.
After nerve injuries, the brain and body of some people stop communicating properly, which means that even the lightest touch can be painful for them.
Scientists at Boston Children's Hospital discovered a brain circuit that normally makes a distinction between the sensation of pain and other tactile sensations, but is interrupted after nerve injuries.
The team hopes to use its discovery one day to & # 39; lower & # 39; the volume of chronic nervous pain.
Scientists discovered this group of neurons, which descends from a sensorial information center in the brain to the spinal cord, where "touch" erroneously translates to "pain"
Up to 10 percent of the American population lives with neuropathic or nervous pain.
The nervous system is such a complex network of constant communication with each other, and damage to any part of this system can make the signals traveling through it go crazy.
This damage, which can be caused by injury or by HIV, shingles or cancer, to name a few, can result in inappropriate feeling messages.
For example, patients may feel burning, tingling or numbness without immediate or obvious cause.
Or the sensations that should be innocuous, like the rubbing of the sheets against the skin, can be unbearable.
The unpredictability can be not only physically uncomfortable but also psychologically torturing.
Anti-inflammatory medications can relieve pressure on nerves and antidepressants, and anticonvulsant medications may be helpful for some people, but for many, nerve pain is as stubborn as it is serious.
Now, the Boston Children & # 39; s scientist has been able to shed some light on why.
They discovered a communication system that acts like a megaphone of sensory information.
A small group of neurons in the brain can receive sensory information from the rest of the body, raise the volume of those signals and send them to the location of the touch, but with much greater intensity.
These signals travel through the spinal cord, which makes some interpretation for our sensory system. The signals can be sent with one of two messages: simply & # 39; tap & # 39; or & # 39; pain & # 39;
"Under normal conditions, the layers of touch and pain of the spinal cord are strongly separated by inhibitory neurons," explains study co-author Dr. Alban Latremoliere.
"After the nerve injury, this inhibition is lost, which leads to tactile information activating the pain neurons.When spinal neurons that are supposed to be painful just send this information to the brain, we feel pain."
When he and his team raised the cluster of neurons they discovered from mice with neuropathic pain or cut them, the animals no longer had adverse reactions to soft touches, but they still responded to real pain, like punctures or heat.
Of course, removing genes or cutting down neurons may not be an option in humans with nerve pain, but the findings gave researchers a goal and a mechanism for future treatments.
"We know that the mental activities of the higher brain (cognition, memory, fear, anxiety) can make you feel more or less pain," says Dr. Clifford Woolf, another co-author of the study.
"Now we have confirmed a physiological pathway that may be responsible for the magnitude of the pain." We have identified a volume control in the brain for pain, now we have to learn to turn it off. "