Topics:
Animal Physiology, Animal Refresher
What EMG Records
Electromyography (EMG) records the electrical activity of:
- Skeletal muscles — Correct Answer
- Smooth muscles
- Cardiac muscles
- Both a & b
Explanation:
Correct Answer: Skeletal muscles
Electromyography (EMG) is a diagnostic technique that records the electrical activity of skeletal muscles — both at rest and during voluntary contraction — using surface electrodes or needle electrodes inserted into the muscle.
EMG Basics
- At rest, normal skeletal muscle shows no electrical activity (electrically silent).
- During contraction, motor units generate action potentials → detected as motor unit action potentials (MUAPs).
- In neuromuscular diseases: abnormal spontaneous activity (fibrillations, positive sharp waves) at rest indicates denervation.
Clinical Uses of EMG
- Diagnosing neuromuscular diseases: myopathy, neuropathy, motor neuron disease.
- Evaluating nerve conduction (combined with Nerve Conduction Studies — NCS).
- In veterinary medicine: diagnosing muscle disorders in horses, dogs, and cattle.
Comparison with Other Electrophysiology Tests
- ECG (Electrocardiography): Records electrical activity of the heart (cardiac muscle).
- EEG (Electroencephalography): Records electrical activity of the brain.
- EMG (Electromyography): Records electrical activity of skeletal muscles.
📚 About this Topic — Animal Physiology
This multiple choice question is from Animal Physiology, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Physiology to strengthen your preparation.
