Final answer:
The statement is true; electrical currents can cause violent muscle contractions, which may lead to involuntary movements or prevent the release of an electrical source. Additionally, conditions like epilepsy also produce seizures with possibly violent muscle contractions due to abnormal brain activity.
Step-by-step explanation:
The statement "The convulsion (seizure) that the electrical current produced is violent" is generally true. When a person experiences an electrical shock, the electrical current can cause muscle contractions that may be involuntary and violent. Depending on the strength of the current, effects can vary from muscular contractions strong enough to 'throw' a person backward, to making it impossible to let go of the source of electricity due to the stronger contraction of muscles that close the fingers compared to those that open them. Moreover, epilepsy is a condition known to cause seizures, which include periods of lost consciousness and potentially violent muscle contractions caused by abnormal electrical activity in the brain. Furthermore, very large currents can be life-threatening, causing the heart and diaphragm to stop during the shock, leading to cessation of breathing and heart function, which may recover post-shock or may require medical intervention such as defibrillation to restore the heart's normal rhythm.