Reciprocal Inhibition
Reciprocal Inhibition: A neuromuscular reflex that may result in a decrease in the activity of the functional antagonist when agonist activity increases. For example, an increase in biceps brachii activity may decrease triceps brachii activity, and an increase in psoas activity may decrease gluteus maximus activity.
- Note: Reciprocal inhibition is likely dictated by innervations between nerve cells and may not always reflect "perfect opposites." For example, an increase in the tensor fascia lata's activity may decrease the gluteus medius's activity (both muscles perform hip abduction).
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Additional neuromuscular reflexes:
- Reciprocal Inhibition
- Autogenic Inhibition
- Arthrogenic Inhibition
- Nociceptive Motor Control Alterations
- Stretch Reflex
- Neuromuscular Inhibition
Frequency Asked Questions
What is a technique incorporating reciprocal inhibition?
- PNF in Practice by Beckers and Buck includes a technique called "PNF agonist-antagonist stretching," which includes both an agonist contraction as well as a contraction of the antagonist to take advantage of reciprocal inhibition to achieve more extensibility from the target muscle.
What induces reciprocal inhibition?
- Reciprocal inhibition is a reflex that is induced when agonist muscles activate inhibitory interneurons (within the spinal cord), which act to inhibit the motor neurons of antagonists. This likely results from inhibitory neurons changing the threshold needed for agonist motor neurons to reach their action potential.
What is an example of reciprocal inhibition?
- Reciprocal inhibition occurs during most motions to aid in movement efficiency. For example, when you flex your elbow, your biceps brachii (and other muscles) contract, and triceps are reciprocally inhibited to allow for smoother motion.
History
Reciprocal Inhibition is also known as Sherrington's Law of Reciprocal Innervation or Sherrington's Law II. Although Descartes may have been the first to publish an observation of this relationship between muscles as early as 1648 (1), it was Nobel Laurette Sir Charles Scott Sherrington who demonstrated this phenomenon and proposed a theory of synaptic communication of the nervous system in his seminal work in 1906 (2). This theory of the "synapse" laid the foundation for our current understanding of central nervous system communication. New technology and research have led to a far more nuanced understanding of the nervous system, neuromuscular reflex, and reciprocal inhibition; however, conceptually, his definition of reciprocal inhibition still holds true.
- Descartes, Rene (1648). La description du corps humaine (The Description of the Human Body ). Published posthumously by Clerselier in 1667
- Sherrington, Charles Scott (1906). The integrative action of the nervous system (1st ed.). Oxford University Press: H. Milford. pp. xvi, 411 p., [19] leaves of plates.