Proprioception refers to the body’s ability to perceive its own position in space. For example, proprioception enables a person to close their eyes and touch their nose with their index finger.
Other examples of proprioception include:
In addition, proprioception allows the body to perform simultaneous actions without stopping to think about each one separately, such as running while dribbling a basketball. 1 Lephart SM, Pincivero DM, Giraldo JL, Fu FH. The role of proprioception in the management and rehabilitation of athletic injuries. Am J Sports Med. 1997;25(1):130-7.
Proprioception is necessary for precise and fluid movements, making it essential to athletes and non-athletes alike. This article discusses how proprioception works, how injuries can impair proprioception, and how to improve proprioception through specific exercises.
Muscle spindles, the proprioceptors in the muscle, are long proteins that lay parallel to muscle fibers.
Proprioception relies on the relationship between the body’s central nervous system and certain soft tissues, including muscles, tendons, and ligaments.
Within these tissues are sensory organs called proprioceptors. Sensory nerve endings wrap around the proprioceptors to send information to the nervous system. The proprioceptors can sense when tissues are stretched or experience tension and pressure.
For example, the proprioceptors in muscles are called muscle spindles. Muscle spindles are long proteins encapsulated in sheaths that lay parallel to muscle fibers. They work as follows:
How proprioception works in the muscle.
The entire process takes less than a millisecond and, in some cases, it happens so quickly that it is referred to as a “reflex.” This feedback loop works continually; even when a person is sleeping the brain maintains some level of sensory input.
This continual feedback loop is critical to everyone, especially athletes. For example, a runner can seamlessly transition from soft grass to hard concrete and back again, making unconscious, minor adjustments to stay upright and maintain balance. The runner does not have to think about changing leg and feet movements to accommodate the change in terrain.
The proprioceptors in tendons are called Golgi Tendon Organs (GTOs), and they work similarly to muscle spindles. In ligaments, there is a neural feedback with our muscles that is still being studied and clearly defined by researchers. However, it is been understood that impaired/torn ligaments produce deficits in proprioceptive abilities.
An injury, such as a torn ACL or a strained Achilles tendon, damages the soft tissue where the proprioceptors are located. Damaged tissues do not function normally and thereby resulting in a loss of proprioception. This loss of proprioception can lead to:
See What Is the Difference Between Tendonitis, Tendinosis, and Tendinopathy?
For this reason, healthcare providers emphasize the importance of injury healing and rehabilitation.
Since proprioception is linked to the central nervous system it can also be impaired by neurological conditions, such as Parkinson’s Disease and Multiple Sclerosis.
Next Page: Simple Exercises to Restore Proprioception
This is a review of the proprioceptive senses generated as a result of our own actions. They include the senses of position and movement of our limbs and trunk, the sense of effort, the sense of force, and the sense of heaviness. Receptors involved in proprioception are located in skin, muscles, and joints. Information about limb position and movement is not generated by individual receptors, but by populations of afferents. Afferent signals generated during a movement are processed to code for endpoint position of a limb. The afferent input is referred to a central body map to determine the location of the limbs in space. Experimental phantom limbs, produced by blocking peripheral nerves, have shown that motor areas in the brain are able to generate conscious sensations of limb displacement and movement in the absence of any sensory input. In the normal limb tendon organs and possibly also muscle spindles contribute to the senses of force and heaviness. Exercise can disturb proprioception, and this has implications for musculoskeletal injuries. Proprioceptive senses, particularly of limb position and movement, deteriorate with age and are associated with an increased risk of falls in the elderly. The more recent information available on proprioception has given a better understanding of the mechanisms underlying these senses as well as providing new insight into a range of clinical conditions.
Understand the relationship between the terms kinesthesia and proprioception.
Be able to explain how the knee-jerk reflex works.
Proprioception is the sense of the relative positioning of neighboring parts of the body, and the sense of the strength of effort needed for movement. It is distinguished from exteroception, by which one perceives the outside world, and interoception, by which one perceives pain, hunger, and the movement of internal organs. A major component of proprioception is joint position sense (JPS), which involves an individual’s ability to perceive the position of a joint without the aid of vision. Proprioception is one of the subtler sensory systems, but it comes into play almost every moment. This system is activated when you step off a curb and know where to put your foot, or when you push an elevator button and control how hard you have to press down with your fingers.
Kinesthesia is the awareness of the position and movement of the parts of the body using sensory organs, which are known as proprioceptors, in joints and muscles. Kinesthesia is a key component in muscle memory and hand-eye coordination. The discovery of kinesthesia served as a precursor to the study of proprioception. While the terms proprioception and kinesthesia are often used interchangeably, they actually have many different components. Often the kinesthetic sense is differentiated from proprioception by excluding the sense of equilibrium or balance from kinesthesia. An inner ear infection, for example, might degrade the sense of balance. This would degrade the proprioceptive sense, but not the kinesthetic sense. The affected individual would be able to walk, but only by using the sense of sight to maintain balance; the person would be unable to walk with eyes closed. Another difference in proprioception and kinesthesia is that kinesthesia focuses on the body’s motion or movements, while proprioception focuses more on the body’s awareness of its movements and behaviors. This has led to the notion that kinesthesia is more behavioral, and proprioception is more cognitive.
Reflexes combine the spinal sensory and motor components with a sensory input that directly generates a motor response. The reflexes that are tested in the neurological exam are classified into two groups. A deep tendon reflex is commonly known as a stretch reflex and is elicited by a strong tap to a tendon, such as in the knee-jerk reflex. A superficial reflex is elicited through gentle stimulation of the skin and causes contraction of the associated muscles.
Fig.3.1.1. Knee-jerk Reflex. This iIllustrates the patellar reflex, also known as a myotatic reflex, the stretch reflex, and the knee-jerk reflex. (Credit: Amiya Sarkar. Provided by: Wikipedia License: CC-BY-SA 4.0.)
Knee-jerk reflex, also called patellar reflex, is a sudden kicking movement of the lower leg in response to a sharp tap on the patellar tendon, which lies just below the kneecap (Fig.3.1.1). One of the several positions that a subject may take for the test is to sit with knees bent and with one leg crossed over the other so that the upper foot hangs clear of the floor. The sharp tap on the tendon slightly stretches the quadriceps, the complex of muscles at the front of the upper leg. In reaction, these muscles contract and the contraction tends to straighten the leg in a kicking motion. Exaggeration or absence of the reaction suggests that there may be damage to the central nervous system. The knee jerk can also be helpful in recognizing thyroid disease.
If you want to learn more about reflexes, watch this youtube video or follow this link to OpenStax Textbook chapter on Sensory and Motor Exams.
Take a minute to answer these questions in your notes:
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Lumen Learning, Boundless Psychology, Sensory Processes Provided by: Boundless.com. URL: https://courses.lumenlearning.com/boundless-psychology/chapter/sensory-processes/
OpenStax, Anatomy and Physiology Chapter 16.4 The Sensory and Motor Exams Provided by: Rice University. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction
License: CC BY 4.0
Encyclopaedia Britannica, Knee-Jerk Reflex URL: https://www.britannica.com/science/knee-jerk-reflex
License: CC BY-NC 3.0 US