Mechanoreceptors


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Related to Mechanoreceptors: Photoreceptors, Chemoreceptors, electromagnetic receptors

Mechanoreceptors

Sensory receptors that provide the organism with information about such mechanical changes in the environment as movement, tension, and pressure. In higher animals receptors are actually the only means by which information of the surroundings is gained and by which reactions to environmental changes are started. See Sensation

Mechanoreceptors are excited by mechanical disturbances of their surroundings through deformation of their structure, through pressure or tension, or through a combination of these. In general, little energy is required for mechanical stimuli to cause a detectable excitation in mechanoreceptors.

From a physical point of view, mechanoreceptors are energy transducers; they convert mechanical into electrical energy, which in turn triggers the nerve impulse. Deformation leads to a sequence of events which may be summarized by the following scheme: The generator current is the earliest detectable sign of excitation. The most salient characteristic of the generator current is its graded nature; its amplitude increases continuously, without visible steps, if the stimulus strength is progressively increased. When the generator current reaches a certain critical amplitude, an all-or-nothing potential is discharged in the sense organ which may then propagate as an all-or-nothing nerve impulse along the afferent axon of the receptor. See Nervous system (invertebrate), Nervous system (vertebrate)

Mechanoreceptors

 

sensory nerve endings that receive various mechanical stimuli from the external environment or viscera.

Some mechanoreceptors, called tactile receptors and concentrated in the outer integuments of animals and man, are sensitive to touch. Baroreceptors (pressoreceptors, volumoreceptors), found in the walls of the blood vessels, the heart, and hollow smooth-muscled organs, react to distension associated with elevated blood pressure or accumulated gases in the stomach or intestine. Proprioceptors are mechanoreceptors found in the musculoarticular apparatus that react analogously to the contraction or relaxation of the skeletal muscles. The mechanoreceptors of the vestibular apparatus, called vestibuloreceptors, respond with neural impulses to acceleration, vibration, or inclination of the body or head. The specific characteristics of a stimulus are coded in the mechanoreceptors by the frequency and rhythm of their impulses.

References in periodicals archive ?
Gardner discloses mechanoreceptors are activated by strong stimuli: sharp, pricking sensations.
The dominance of mechanoreceptor structures could be explained by the subterranean habits of mole crickets and limited air movement.
Several investigators already showed increased muscle activity following joint afferent fiber or mechanoreceptor stimulation and activation of gamma motor neurons (42,43).
This structure, which is covered by a variety of mechanoreceptors, first appears at the base of the antennules during larval stage VII.
Apart from the sensory receptors in the skin such as Merkel's Discs, Meissner's corpuscles and Free Nerve Endings, there are key intra-fascial mechanoreceptors that are activated during a treatment.
Current results indicated to the presence of pores on sensilla and presence or absence of pores in the structure of sensilla affect on the functions of antennae in ant, whereas it was reported that nonporous sensilla trichodea are mechanoreceptors while those with pores are contact and volatile chemoreceptors [8].
The tissue was also strewn with special types of neurons called mechanoreceptors, which respond to distortion or pressure.
via mechanoreceptors and chemoreceptors) is analysed by a central controller which also considers variables such as time to endpoint (e.
Since an intermittent finger velocity distorts the space-time relations with which raised dots cross receptive fields of mechanoreceptors in the fingerpads (see, for example, Connor & Johnson, 1992; Hughes & Jansson, 1994) and may make the identification of letters more difficult, one may presume that this intermittency is not intentional but is an unintended consequence of other processing demands.
Mechanoreceptors are the units that convert tactile stimuli into neuron excitations and are of two types: static--Ruffini corpuscles and Merkel receptors and dynamic--Meissner cells and Pacini corpuscles.
Merkel cells are derived from the neuroectoderm and function as type I mechanoreceptors by forming synapselike contacts with the tactile hair discs of Pinkus.