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Vitamin B12 primarily exists in animal products, including meat, fish, poultry, and milk. Another example is tabes dorsalis, a late manifestation of tertiary syphilis. It causes degenerative joints disease Charcot joints , Argyll Robertson pupils light reflex lost but accommodation reflex retained , and affects dorsal column.
Tabes dorsalis incidence is reduced dramatically after the introduction of penicillin in the treatment of syphilis. An infarction of the posterior spinal artery also affects the posterior column pathway resulting in the loss of vibration, proprioception, and light touch below the level of the lesion.
Hemisection of the spinal cord, known as Brown-Sequard syndrome, also affects the dorsal column along with other pathways. It is commonly the result of trauma, tumors, and abscesses. This book is distributed under the terms of the Creative Commons Attribution 4. Turn recording back on. National Center for Biotechnology Information , U.
StatPearls [Internet]. Search term. Introduction Our somatosensory system has three basic types of sensory receptors that detect different types of external stimuli. Issues of Concern The most significant concern related to vibration sensation is the peripheral neuropathy of diabetes mellitus, which affects the peripheral nerves and results in the loss of pain, temperature, and vibration sensations.
Cellular Pacinian corpuscles PCs are highly specialized corpuscles found in the dermis of glabrous skin. Development The development of Pacinian corpuscles PCs starts at the gestational age of 13 weeks and is completed at the age of 4 months postnatal. Organ Systems Involved The sense of vibration is perceived and conducted to the brain via integumentary and nervous systems.
Function The function of vibratory receptors is to make us aware of different frequencies of external stimuli. Mechanism Pacinian and Meissner corpuscles are located in the deep dermis and detect distortion of skin from external stimuli and transmit it to the central neurite.
Related Testing The Romberg test assesses the integrity of the posterior column pathway, which carries vibratory sensations. Pathophysiology The pathophysiology of vibration perception and its pathways is related to the diseases affecting the dorsal column.
Clinical Significance The clinical significance of vibratory sensation lies in its carrier pathway DCML , which also carries position sense and fine touch. Review Questions Access free multiple choice questions on this topic. Comment on this article. Ruffini Endings or Corpuscles are found in the superficial dermis of both hairy and glaborous skin where they record low-frequency vibration or pressure. These receptors adapt slowly to pressure that results in stretching of the skin.
They record the sustained presence of pressure on the skin. Pacinian corpuscles: Pacinian corpuscles, such as these visualized using bright field light microscopy, detect pressure touch and high-frequency vibration. These attributes suggest that Pacinian corpuscles are involved in the discrimination of fine surface textures or other moving stimuli that produce high-frequency vibration of the skin.
Inside the corpuscle is an important conducting structure called the first node of Ranvier. It is also here that the nerve sheath, made of an electrically insulating material known as myelin , begins.
In nerves that have a myelin sheath , conduction of electrical impulses is relatively fast because a whole series of nodes of Ranvier are present, extending from the first one inside the sensory receptor.
The nodes are able to rapidly transmit changes in electrical potential to one another. When a stimulus is continually present, nerve impulses are fired off less and less over time. They, too, are found primarily in the glabrous skin on the fingertips and eyelids. Tactile is flat and lamellated has a shape. A functional difference is that tactile provides fine touch, to judge texture including the lips, palms and nipples. These receptors respond to indentation of the skin.
They adapt slowly to pressure, and therefore record the sustained presence of pressure on the skin. Microscopically they are relatively large, myelinated nerve endings.
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