Question

What does reciprocal inhibition mean?

1) One sensory nerve is stimulated while another sensory neuron in the same area is inhibited and cannot respond.
2) One sensory nerve is stimulated while another sensory neuron in the same area is also stimulated.
3) One sensory nerve is inhibited while another sensory neuron in the same area is also inhibited.
4) One sensory nerve is inhibited while another sensory neuron in the same area is stimulated.

Answer 1

Reciprocal inhibition refers to a neurological process where the activation of one nerve results in the inhibition of another, ensuring efficient motor responses like those seen in the withdrawal reflex by preventing opposing muscle contraction.

Step-by-step explanation:

Reciprocal inhibition is a concept in neurophysiology where the activation of one neuron leads to the inhibition of another. This can be observed clearly in reflex actions, such as the withdrawal reflex. When a painful stimulus is encountered, a sensory nerve sends a signal to the spinal cord, which then stimulates the motor neurons involved in withdrawing the affected body part. Concurrently, reciprocal inhibition ensures that opposing muscles, such as the triceps when the biceps contract, are not activated, which would counteract the withdrawal. This process is apparent in the withdrawal reflex, where activation of ventral horn motor neurons causes the biceps brachii to contract, while a collateral branch of the sensory axon inhibits the opposing triceps brachii muscle, preventing it from contracting and potentially slowing down the withdrawal motion. Moreover, this principle plays a role in the cross-extension reflex, providing balanced movements on both sides of the body when required.