Question

Q6. Electrocardiograph is an instrument used in the study of the .
in one to three words ​

Answer 1

Answer:

The Electrocardiograph

The electrocardiograph (ECG) is an instrument that records surface potentials associated with the electrical activity of the heart. The surface potentials are conducted to the instrument by metal contacts called electrodes which are fixed to various parts of the body. Usually the electrodes are attached to the four limbs and over the heart. Voltages are measured between two electrodes at a time.

A typical normal signal recorded between two electrodes is shown in Figure. The main features of this wave form are identified by the letters P, Q, R, S, and T. The shape of these features varies with the location of the electrodes. A trained observer can diagnose abnormalities by recognizing deviations from normal patterns.

The rhythmic contraction of the heart is initiated by the pacemaker, which is a specialized group of muscle cells located near the top of the right atrium. Immediately after the pacemaker fires, the action potential propagates through the two atria. The P wave is associated with the electrical activity that results in the contraction of the atria. The QRS wave is produced by the action potential associated with the contraction of the ventricles. The T wave is caused by currents that bring about the recovery of the ventricle for the next cycle.

The electroencephalograph (EEG) measures potentials along the surface of the scalp. Here again electrodes are attached to the skin at various positions along the scalp. The instrument records the voltages between pairs of electrodes. The EEG signals are much more complex and difficult to interpret than those produced by the electrocardiograph. The EEG signals are certainly the result of collective neural activity in the brain. However, so far it has not been possible to relate unambiguously the EEG potentials to specific brain functions.