Question

• Describe the source of the EMG signal and what the shape of the signal represents in the patient.

• How is the source of an EEG signal located on an individual?

• How does a cochlear implant allow a patient to hear different frequencies?

• What does an ECG measure?

• Can cardiac ablation be used to treat under-active cardiac tissue? Explain.

Answer 1

1) EMG is a technique for examining the electrical activity of skelital muscles. The EMG electrodes gets signals from receptor organs passed through various neurons into the brain and transmit the converted information to the muscles, and the sources of EMG signals detected through the contraction of muscle membrane. The shape, frequency and size are completely judges on the basis of action potentials. It also helps the patient to find and train the muscles.

2) The electrical activity of brain is noninvasive in which the electrodes are placed along the scalp. It helps to record all electrical activity over a period of time. The main EEG waves used are delta, theta, alpha and beta.

3) The cochlear implants start its function by converting the sounds in the implanted electrodes into signals to determine the frequency of a sound which is sent to cochlea and consider it as sound or pitch. The amplitude determines a sound's volume by the height of each wave.

4) ECG is a test to measure the electrical activity of the heart. It also helps to detect any heart anomalies like MI and also helps to get informations regarding blood pressure which is a risk factor of enlarged heart ,heart rate, and rhythm.

5) The catheter ablation is definitly used to treat the under-active tissues. The cardiac ablation is used in the treatment of arrhythmias by making a small scar in heart tissue which may get destroyed due to the procedure. It also helps to treat Atrial fibrillation.