What Are the Proprioceptors?

Proprioceptors refer to devices such as sensory nerve endings located at motor organs such as muscles, tendons, joint capsules, and ligaments. Proprioceptors can sense changes in muscle tension and pressure, sense the extent of joint expansion, and convert the stimulation signals of these sensory changes into nerve impulses that are transmitted to the cerebral cortical body movement center to regulate the movement of skeletal muscles and make people feel the body in space Changes in position, posture, movement, etc.

Proprioceptors refer to devices such as sensory nerve endings located at motor organs such as muscles, tendons, joint capsules, and ligaments. Proprioceptors can sense changes in muscle tension and pressure, sense the extent of joint expansion, and convert the stimulation signals of these sensory changes into nerve impulses that are transmitted to the cerebral cortical body movement center to regulate the movement of skeletal muscles and make people feel the body in space Changes in position, posture, movement, etc.

Chinese name

Proprioceptor

Foreign name

proprioceptors

Location

Receptors in muscles, tendons and joints

nickname

Proprioceptors

Overview of proprioceptors

Proprioceptors located in skeletal muscle include muscle spindles and tendon spindles. Muscle spindle is a spindle-shaped sensor located in the muscle, located between the muscle fibers and arranged parallel to the muscle fibers. Muscle spindles are widely distributed in human skeletal muscles, mainly concentrated in the skeletal muscles of the hands and feet of the limbs. The muscle shuttle can feel the change in muscle length. When the muscle is stretched and the length changes, the sensory nerve fiber ends in the muscle shuttle receive the corresponding stimulus and are activated. The stimulus signal is transmitted from the afferent nerve fiber to the center. Can cause contracted muscles. The tendon spindle is also known as the Golgi organ or tendon organ. It is mainly distributed between the tendon collagen fibers and in series with the extrafusal muscle fibers. It can sense the muscle tension. The tendon spindle is similar to the muscle spindle in structure, and it is also composed of several tendon fiber bundles wrapped around sensory nerve fiber ends and enclosing connective tissue capsules. When the muscle is subjected to external or internal pressure to increase the muscle contraction tension, the muscle spindle will be activated by the stimulation signal, the afferent nerve fibers will transmit the nerve impulses to the central nervous system, and finally relax the muscle.

The proprioceptors located in connective tissue such as the joint capsule, ligaments, periosteum, and interfacial space include Rulini endings (RE), Pacinian corpuscles (PC), and Golgiedon organ like ending GrOE), free nerve end (Fee nerve end, FNE) 4 types, RE belongs to slow adaptation, low threshold stretch sensor can sense the static position of the joint, internal pressure and changes in angle, velocity and angular velocity during exercise. PC has the characteristics of fast adaptation and low threshold, and its role is to generate and transmit joint motion sense, and to sense joint position changes. GTOE is a slow-adapting, high-threshold sensor, which has little effect when the joint is stationary and moving, and can sensitively sense ligament tension when the joint moves to the extreme position. FNE is a non-sheathed nerve ending, its role is to sense arthritis and Pain stimuli are also characterized by high thresholds.

Proprioceptor proprioception

Proprioceptive sensation, also known as the "sixth sense" of the human body, refers to the sensory information of the human body that activates muscles in changes in direction, spatial position, and speed, and is transmitted to the central nervous system. After judgment is made by the brain, muscles, joints, etc., the corresponding Control behavior. Or it can be expressed as information that the human body can determine where the body and limbs are while performing various activities. According to different angles, proprioception can be divided into balance and motion perception systems, or position and motion perceptions, or dynamic proprioception and static proprioception. Various classification methods include three aspects: (1) the static perception of joint position; (2) the perception of joint motion (the perception of joint motion or acceleration); (3) the reflection response and the transmission of muscle tension Mobility. The former two reflect the propensity of proprioceptive activity of the proprioception, while the latter reflect the ability of proprioceptive activity.

Proprioceptor pathway

Part of the information about the muscle tension, length, limb rest position, and movement status that the proprioceptors feel is also uploaded to the cerebral cortex to form proprioception. The first-level neurons of the proprioceptive sensory pathway are spinal ganglion cells, and the surrounding protrusions finally reach the receptors of the muscles, health, and joints; the central protrusions enter the human spinal cord through the medial portion of the posterior root, and rise directly on the medial side of the posterior horn to form the spinal cord . Two bundles can be distinguished in the upper thorax and neck posterior cord: the inner side is a thin bundle, the posterior root fibers from the sixth thorax, conduct the proprioception of the lower part of the trunk and the lower limbs. The lateral side is a wedge bundle, which comes from the posterior root fibers above the sixth thorax, and transmits the proprioception of the upper trunk and upper limbs. The posterior cord fibers enter the medulla oblongata and terminate in the thin bundle nucleus and wedge bundle nucleus. The second-stage fibers they sent forward bypassed the ventral side of the central canal, intersecting the contralateral one at the midline, which is a mastoid crossing. Crossed fibers run on both sides of the medullary midline, called the medial mound system. In the pontine, it occupies the leading edge of the tectum, enters the tectum of the midbrain of the human, lies outside the red nucleus, and stops upward at the lateral nucleus of the thalamus.

Proprioceptor regulation

1. Analysis from the perspective of anatomical structure:

The function of proprioception mainly refers to the control of the trunk and limbs, which is realized by the nervous system through the coordination of skin sensations such as tendon spindles, muscle spindles, and ligaments, and the adjustment of local joint and muscle tension. If proprioceptive sensation declines and the nervous system's ability to control is reduced, then the chances of injury to the body will also greatly increase. When the human body is in motion, due to the external load, the tension and length of tissues such as muscles are changed, which causes the proprioceptive sensory receptors in the tissue, such as the Golgi apparatus and the toroidal apparatus, to excite. These receptors transmit the excitement to the central nervous system and integrate information analysis Through the reflex neuromuscular feedback mechanism, the motor responds appropriately to the three levels of motion control of the spinal cord reflex, cognitive system, and brain system.

2. Analysis from physiological mechanism:

When the proprioceptor is mechanically stimulated, the permeability of some cation channels of the receptor's cell membrane increases, causing membrane potentials to depolarize, resulting in sensory or generator potentials. These two potentials will pass through the afferent nerve, generate nerve impulses, and upload them. This process is mainly conducted in the form of electrical tension spread. For example, when mechanical stretching will open the Ca channels in the sensory peripheral end of the muscle spindle, Ca inflow generates depolarized sensory potentials, and then it acts on the sensory fibers in the form of electrical tension spreading, activating the Ca2 + channel opening, causing Ca to increase. , Generate muscle spindle potentials, further activate Na channels, and generate neural activity on afferent nerve fibers.

3. Analysis from the degree of sports participation:

In theory, proprioception feels involved in any sport, but not directly. It controls the muscles and joints to adjust the posture of various parts of the body, maintains a balanced balance, and provides sufficient preparation for the completion of the movement. At the same time, it can also promote the recovery of the body balance after the movement.