Biomedical Engineering Reference
In-Depth Information
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TIME (ms)
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FIGURE 11.1
(a) Electrogram recorded from the surface of a pig's heart during normal sinus rhythm.
(b) Electrogram recorded from the surface of the same pig's heart during ventricular fibrillation (VF). (Sampled
at 1,000 samples/s.)
magnetic activity from the brain (magnetoencephalography, MEG), peripheral nerves
(magnetoneurography, MNG), gastrointestinal tract (magnetogastrography, MGG), and
the heart (magnetocardiography, MCG).
11.2.3 Biochemical Signals
Biochemical signals contain information about changes in concentration of various chem-
ical agents in the body. The concentration of various ions, such as calcium and potassium,
in cells can be measured and recorded. Changes in the partial pressures of oxygen (P
O
2
) and
