Clinical Uses Of Electrical Stimulation

Clinical electrical stimulation is simply the application of electrical currents to a body, be it for function or therapy. As we just discussed, the current of electrons passing through the wires is converted into a current of ions moved within the tissue, which are in turn capable of transporting electrical charge across the membranes of excitable tissues. The purpose of these applied currents is to cause the targeted depolarization of nerve and or muscle to threshold. The most common clinical...

Electrode 2

Ems Stimulation Amplifier

Figure 7.19 Circuit of a battery-powered, two-channel TENS unit. IC1 produces a pulse every time the stimulation channels need to be triggered. The trigger frequency can be varied between 3 and 100 Hz. Burst TENS is activated when SW2 connects the reset line of timer IC3 periodically to inhibit IC1 from oscillating. Modulated TENS is enabled by closing SW3, which allows a triangle wave generated by IC2 to modulate the frequency of IC1. The electrodes are driven by step-up transformer Tl....

Biopotential Amplifiers

Power Line Radiation

In general, signals resulting from physiological activity have very small amplitudes and must therefore be amplified before their processing and display can be accomplished. The specifications and lists of characteristics of biopotential amplifiers can be as long and confusing as those for any other amplifier. However, for most typical medical applications, the most relevant amplifier characterizing parameters are the seven described below. 1. Gain. The signals resulting from...