limen /li·men/ (li´men) pl. li´mina [L.] a threshold or boundary.
limen.
limen of insula , limen in´sulae the point at which the cortex of the insula is continuous with the cortex of the frontal lobe.
limen na´si the ridge marking the boundary between the vestibule of the nose and the nasal cavity proper.
li·men (l  m n)n. pl. li·mens or lim·i·na (l  m-n) 1. The threshold of a physiological or psychological response. 2. The external opening of a canal; an entrance. lim i·nal (lm-nl) adj. |
limen.
See threshold stimulus.
limen
pl. limina [L.] a threshold or boundary.
insula limen, limen insulae
the point at which the cortex of the insula is continuous with the cortex of the frontal lobe.
limen pharyngoesophagaeum
a mucosal ridge where the pharynx becomes the esophagus.
threshold
The value of a stimulus that just produces a response. Syn. limen.
absolute threshold The minimum luminance of a source that will produce a sensation of light. It varies with the state of dark adaptation, the retinal area stimulated, the wavelength of light, etc. Syn. light threshold. See photochromatic interval.
contrast threshold See differential threshold.
corneal touch threshold See corneal touch threshold.
differential threshold The smallest difference between two stimuli presented simultaneously that gives rise to a perceived difference in sensation. The difference may be related to brightness, but also to colour and specifically to either saturation (while hue is kept constant) or hue (while saturation is kept constant). The differential threshold of luminance is equal to about 1% in photopic vision. Syn. contrast threshold (if the difference is one of luminance); just noticeable difference (jnd). See Weber's law; contrast sensitivity.
light threshold See absolute threshold.
movement threshold 1. The minimum motion of an object that can be perceived. 2. The speed at which an object moving between two points just appears to be moving. See hyperacuity; phi movement.
resolution threshold See limit of resolution.
stereo-threshold See stereoscopic visual acuity.
absolute threshold The minimum luminance of a source that will produce a sensation of light. It varies with the state of dark adaptation, the retinal area stimulated, the wavelength of light, etc. Syn. light threshold. See photochromatic interval.
contrast threshold See differential threshold.
corneal touch threshold See corneal touch threshold.
differential threshold The smallest difference between two stimuli presented simultaneously that gives rise to a perceived difference in sensation. The difference may be related to brightness, but also to colour and specifically to either saturation (while hue is kept constant) or hue (while saturation is kept constant). The differential threshold of luminance is equal to about 1% in photopic vision. Syn. contrast threshold (if the difference is one of luminance); just noticeable difference (jnd). See Weber's law; contrast sensitivity.
light threshold See absolute threshold.
movement threshold 1. The minimum motion of an object that can be perceived. 2. The speed at which an object moving between two points just appears to be moving. See hyperacuity; phi movement.
resolution threshold See limit of resolution.
stereo-threshold See stereoscopic visual acuity.
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