Phantom limb pain is a poorly
understood phenomenon, in which people who have lost a limb can experience
severe pain, seemingly located in that missing part of the body. The condition
can be seriously debilitating and can drastically reduce the sufferer's quality
of life. But current ideas on its origins cannot explain clinical findings, nor
provide a comprehensive theoretical framework for its study and treatment. Researchers
Chalmers University of Technology, propose that after an amputation, neural
circuitry related to the missing limb loses its role and becomes susceptible to
entanglement with other neural networks in this case, the network responsible
for pain perception.
Neurons are never completely
silent. When not processing a particular job, they might fire at random. This
may result in coincidental firing of neurons in that part of the sensorimotor
network, at the same time as from the network of pain perception. When they
fire together, that will create the experience of pain in that part of the
body. Through a principle known as Hebb's Law neurons in the sensorimotor and
pain perception networks become entangled, resulting in phantom limb pain. The
new theory also explains why not all amputees suffer from the condition- the
randomness, or stochasticity, means that simultaneous firing may not occur, and
become linked, in all patients.
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