muscle tone
Quick Summary
Muscle tone refers to the continuous, passive partial contraction of muscles. This state is maintained by the nervous system and allows muscles to be ready to respond to stimuli. It's crucial for posture, balance, and smooth movements.1
Muscle spindles, sensory receptors within muscles, play a key role in muscle tone. They constantly report on muscle length and the rate of change in length to the central nervous system. This feedback helps regulate muscle contraction and maintain a desired posture.1
While muscles can regenerate and adapt to use, immobilization leads to muscle wasting and reduced oxidative capacity. Conditions like myotonia involve difficulty relaxing a muscle after contraction, often due to issues with the muscle fiber membrane's electrical activity. Dystonias are sustained muscular contractions causing abnormal postures, stemming from diseases of the basal ganglia.23
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human sensory receptionNerve functionā¦receptors is the maintenance of muscle tone (partial contraction) to permit rapid response (fast reaction time) to stimulation. In normal conditions the muscle has tone and is ready to respond; but, when it is without motor stimulation (deafferented), the muscle is flaccid, showing little tone. Upright posture depends on theā¦
Read Moreā¦receptors is the maintenance of muscle tone (partial contraction) to permit rapid response (fast reaction time) to stimulation. In normal conditions the muscle has tone and is ready to respond; but, when it is without motor stimulation (deafferented), the muscle is flaccid, showing little tone. Upright posture depends on theā¦
Read More- sleepREM sleep
ā¦EEG, intermittent REMs, and suppressed muscle tone. The decrease in muscle tone and a similarly observed suppression of spinal reflexes are indicative of heightened motor inhibition during REM sleep. Animal studies have identified the locus ceruleus (or locus coeruleus), a region in the brainstem, as the probable source of thatā¦
Read Moreā¦EEG, intermittent REMs, and suppressed muscle tone. The decrease in muscle tone and a similarly observed suppression of spinal reflexes are indicative of heightened motor inhibition during REM sleep. Animal studies have identified the locus ceruleus (or locus coeruleus), a region in the brainstem, as the probable source of thatā¦
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