Inverse Myotatic Reflex

Definition

The inverse myotatic reflex, also known as the Golgi tendon reflex, is a protective mechanism that helps prevent muscle and tendon damage by inhibiting muscle contraction when excessive tension is detected. It is a key component of the motor responses discussed in section 14.3.

5 Must Know Facts For Your Next Test

1. The inverse myotatic reflex is a protective mechanism that inhibits muscle contraction when excessive tension is detected in the muscle-tendon unit.
2. The Golgi tendon organ, located at the muscle-tendon junction, is the sensory receptor that triggers the inverse myotatic reflex.
3. The inverse myotatic reflex helps prevent muscle and tendon damage by reducing muscle force output when high tension is sensed.
4. This reflex is important during activities that involve high muscle forces, such as weightlifting or sudden changes in muscle length.
5. The inverse myotatic reflex is mediated by inhibitory interneurons in the spinal cord, which block the excitation of the alpha motor neurons that would normally cause muscle contraction.

Review Questions

• Explain the role of the Golgi tendon organ in the inverse myotatic reflex.
  • The Golgi tendon organ, located at the junction of the muscle and tendon, is the sensory receptor that triggers the inverse myotatic reflex. When the muscle-tendon unit experiences excessive tension, the Golgi tendon organ detects this and sends inhibitory signals to the spinal cord. This, in turn, blocks the excitation of the alpha motor neurons, reducing muscle contraction and preventing potential damage to the muscle and tendon.
• Describe how the inverse myotatic reflex differs from the myotatic (stretch) reflex.
  • The myotatic (stretch) reflex is a spinal reflex that causes a muscle to contract in response to stretching of the muscle, mediated by the muscle spindle. In contrast, the inverse myotatic reflex, also known as the Golgi tendon reflex, is a protective mechanism that inhibits muscle contraction when excessive tension is detected in the muscle-tendon unit, as sensed by the Golgi tendon organ. The inverse myotatic reflex serves to prevent muscle and tendon damage, while the myotatic reflex helps maintain muscle tone and stability.
• Analyze the importance of the inverse myotatic reflex during high-force activities, such as weightlifting.
  • The inverse myotatic reflex is particularly important during activities that involve high muscle forces, such as weightlifting. When the muscle-tendon unit experiences excessive tension, the Golgi tendon organ triggers the inverse myotatic reflex, which inhibits further muscle contraction. This helps prevent damage to the muscle and tendon by reducing the force output. Without this protective mechanism, the high forces generated during activities like weightlifting could potentially lead to muscle strains, tendon tears, or other musculoskeletal injuries. The inverse myotatic reflex is a critical safety feature that allows individuals to engage in high-force activities without risking serious harm to their musculoskeletal system.

Related terms

Myotatic Reflex:

The myotatic reflex, or stretch reflex, is a spinal reflex that causes a muscle to contract in response to stretching of the muscle.

Golgi Tendon Organ:

The Golgi tendon organ is a sensory receptor located at the junction of the muscle and tendon that detects changes in muscle tension.

Muscle Spindle: Muscle spindles are sensory receptors within the muscle that detect changes in muscle length and rate of change, triggering the myotatic reflex.