Photo: Morteza Nikoubazl / Reuters
Scientists of the Technological University of Chalmers (Sweden) proposed a new hypothesis explaining the appearance of the phantom limb and associated pain. According to experts, the neural network responsible for the operation of an amputated arm or leg tend to become entangled with nerve pathways that generate the pain. This publication reports ScienceDaily.
According to one of the existing hypotheses, phantom limb can appear as a result of damaged nerves at the amputation that settle in connective tissue and form a new, malfunctioning neurons, which causes pain in the cult. Another point of view suggests that a specific neural network — NeuroMatrix — processes the signals coming from different parts of the body and forms a response signal that is recognized as pain. Finally, an Indian neurologist, Vilayanur Ramachandran suggested that there is a reorganization of the somatosensory cortex, the part of the brain corresponding to the amputated limb starts to receive signals from other parts of the body.
In his new work Max Ortiz Catalan (Max Ortiz Catalan) proposed a new hypothesis, called the stochastic complexity (stochastic entanglement). The area of the brain that were previously processed signals from the missing limb is in a dormant state and never sends motor signals, causing the arm or leg in motion. However, the neurons can be randomly excited. If at the same time the excitation of pain neurons, there is a feeling of pain in the amputated limb.
According to Catalan, such sporadic “outbreaks” in neural networks normally are part of the “noise” and not stand out. However, people with amputated body parts random activity of nerve cells can become fairly significant, because no other signals, masking her. According to the rule of Hebb, if one neuron excites another, communication between them improves with time. So excited coincidence neurons can make a significant contribution to the initiation of adjacent nerve cells responsible for pain.
Scientist have proposed a new method of treatment of phantom pain. The electrodes installed on the cult, intercept neural signals intended for the amputated limb, and transmit them to the computer, which translates them into movements of the virtual hand. Patients can see digital a limb and you can control it, which stimulates the formation of new neural connections that weaken or forestall tangling with the pain centers.
Video, photo All from Russia.