British researchers found about a third to reduce the number of ticks in 19 patients with Tourette syndrome with electrical stimulation of the median nerve through the wrist. Stimulation was carried out rhythmically in the mu range (10 Hertz): preparatory experiments showed that stimulation of the wrist in the mu range affects the corresponding activity in the sensorimotor cortex of the contralateral hemisphere. In the future this method of stimulation because of the comparative ease of use can be applied for the relief of tics in Tourette’s syndrome and outside laboratory practice, write scientists in Current Biology.
As with many disorders that arise in the course of brain development, pathology of Tourette’s syndrome is associated with a change in the balance of work of excitatory and inhibitory neurons result in the syndrome experience intermittent tics — motor and vocal. Despite the fact that tics appear suddenly, most patients with Tourette’s syndrome reportedthat before will himself tick, they feel a certain tension — something like the desire to jerk or cry out, and the tick, accordingly, is relieved of this desire.
Such “training” to the appearance of teak means that the tick can prevent and even effectively get rid of it — for example, using a non-invasive stimulation. Try it decided scientists led by Stephen Jackson (Stephen Jackson) the University of Nottingham. They focused on brain activity in the mu band (8 to 13 Hz) — it is considered characteristic of sensorimotor activity.
Instead of stimulation of the cortex invasive or non-invasive scientists tried the stimulation through the median nerve that runs from the shoulder joint to the wrist — through the signals that go on in the brain. In order to verify the validity of this method, scientists conducted an experiment with participation of 20 volunteers, which stimulated right hand, and the activity of sensorimotor cortex was recorded in the right hemisphere by using EEG.
An electrical signal with a frequency of 12 Hertz sent either rhythmically, every 83 milliseconds for 749 milliseconds or ritmichno — random time intervals. In contrast to arrhythmic under rhythmic stimulation, the scientists were able to register the activity in the mu range (just 12 Hz) in sensorimotor cortex. After rhythmic stimulation, scientists also noticed a small residual activity in the beta range.