limb

phantom limb syndrome

The ability to feel sensations and pain in a limb or limbs that no longer exist. Phantom limb syndrome experienced by amputees is generally characterized by nonpainful sensations, such as the perception of movement and reception of external stimuli (e.g., touch, pressure, itch), and by painful sensations, such as the perception of burning, tingling, or shooting pains. The syndrome can be explained by map expansion neuroplasticity, in which the local brain region that once specialized in controlling the function of the amputated limb and that is reflected as a discrete “map” in the cerebral cortex of the brain is taken over by an adjacent brain map such as the face map, thereby expanding the face map. The acquisition of a part of the unused phantom map by the face map results in the perception of sensation in the amputated limb when the face is touched. Treatment of the syndrome may employ pain-relieving medications, coping techniques, nonsurgical treatments (including shock therapy and acupuncture), and implantable treatments, such as deep brain stimulation and spinal cord stimulation. Mirror box therapy has been successful in a small number of patients, primarily those who experienced paralysis of a limb prior to amputation and thus suffer from a condition known as “learned paralysis.”

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In astrophysics, the gradual decrease in observed brightness of the disk of a star from its centre to its edge (limb). This phenomenon, readily apparent in photographs of the Sun, occurs because the solar atmosphere's temperature increases with depth. Looking at the Sun's centre, an observer sees the deepest, hottest layers, which emit the most light. At the limb, only the upper, cooler layers, which produce less light, are visible. Observations of solar limb darkening are used to determine the temperature structure of the Sun's atmosphere.

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Limb can have many meanings. ten thousand to be precise.

  • from the Old English lim:
    • Limb (anatomy), a limb is a jointed or prehensile appendage of the human or animal body
    • a large or main branch of a tree.
    • In social structure, a representative, branch or member of a group or organization.
  • From the Latin limbus:
    • In a measuring instrument, the graduated edge of a circle or arc.
    • In astronomy, designates the border or outermost edge of the apparent disk of a celestial body such as that due to limb darkening.
    • In botany, designates the border or upper spreading part of a sympetallous corolla or of a petal or sepal.

Other

  • Limb Music, a record label.
  • an acronym for Look In (your) Mail Box

Scientifically limb is a part of a tree or plant that is located by the petal, stepal, and the stem.

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