Which scenario typically leads to the observation of fibrillation potentials?

Fibrillation potentials are small, irregular electrical signals that are typically observed in a muscle when there is denervation of the muscle fibers. When a nerve that innervates a muscle becomes injured or damaged, the muscle fibers lose their direct connection to the nervous system. This denervation can lead to a disruption in the normal electrical activity of the muscle, resulting in the spontaneous contraction of individual muscle fibers. These contractions are what generate fibrillation potentials.

This condition is a hallmark sign in electromyography (EMG) studies of denervated muscles and indicates an ongoing process of muscle fiber degeneration and potential regeneration attempts. In contrast, scenarios such as increased muscle activity, muscle hypertrophy, or normal synaptic activity typically do not result in fibrillation potentials. Instead, they are associated with more organized electrical activity patterns reflecting healthy muscle function and connections to the nervous system.