Difference between revisions of "Transcranial Magnetic Stimulation and Brain Plasticity in Post-Stroke Recovery"

   

   

[[File:MagStim.jpeg|thumb|'''Figure 1:''' Magnetic Stimulation]]

Transcranial Magnetic Stimulation (TMS) is a completely harmless technique that allows specific areas of the brain to be stimulated. By generating magnetic fields (1.5 - 2 tesla) of very short duration (< 1 msec) inside a toroid made of copper coils, and bringing the same close to the scalp, a very short-duration current is induced in the underlying brain, with the opposite direction to the current circulating in the toroid, without activating the nociceptors of the skin, muscles, or meninges. This results in painless excitation of the neurons beneath the toroid. TMS allows mapping the connections of the motor system and defining its excitability. The evoked response can be derived from various muscles of the body, including those of the masticatory apparatus. In fact, stimulation of the scalp about 2 cm laterally to the central point of the scalp, identified as Cz according to the International 10-20 System of Jasper, evokes an electromyographic response recordable in the pterygoid and masseter muscles contralateral to the stimulated cortical area.