risorius


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risorius

(rɪˈzɔːrɪəs)
n
a facial muscle responsible for smiling
References in periodicals archive ?
Rarely, if the injection is not performed properly, the risorius muscle may be paralyzed, leading to an asymmetric smile.
The activity of the smile is determined by several facial muscles, like the elevator of the upper lip and wing of the nose, the zygomatic major and minor, the angle of the mouth, orbicularis oris and risorius (4-6, 8-10).
Into the Pit | Where: The Pit, from 11am With Heartwork, Reece, Risorius, The Harringtons, Rhys Davis, Sam Fowke, Winter Coat, Fire Fences, The People The Poet, HalfBlind and Climbing Trees.
Movement Muscles involved Kissing Orbicularis oris Blowing Buccinator, orbicularis oris Lifting Frontalis, corrugator supercilii, and upper eyebrows eyelid orbicularis oculi Smiling Risorius, zygomaticus major, zygomaticus minor, caninus, levator labii superioris, and orbicularis oris TABLE 2: Examples of results provided by SONRIE.
The facial artery is deep to the platysma, risorius, zygomaticus major and minor, levator labii superioris, and levator labii superioris alaeque nasi muscles.
Raising of the zygomatic area for singing need not provoke widening of the eyes, furrowing of the brow, dilating of the nostrils, wrinkling of the nose, or laughter, actions caused by other muscles, including the risorius, the smiling muscles.
The probe tip was placed on the cheek ~10-15 mm lateral to the lip angle, avoiding natural creases in the skin when the underlying muscles (risorius, buccinator, platysma) contracted (Figure 1(d)).
AU FACS name Facial muscle AU1 Inner brow raiser Frontalis (pars medialis) AU2 Outer brow raiser Frontalis (pars lateralis) AU4 Brow lowerer Depressor glabellae, depressor supercilii, and CS AU6 Cheek raiser OO (pars orbitalis) AU7 Lid tightener OO (pars palpebralis) AU9 Nose wrinkler LLSAN AU10 Upper lip raiser LLS, caput infraorbitalis AU12 Lip corner puller Zygomaticus Major AU20 Lip stretcher Risorius AU23 Lip tightener Orbicularis Oris AU25 Lips part Depressor labii inferioris AU27 Mouth stretch Pterygoids, digastric AU45 Blink Contraction OO AU46 Wink OO AU Videotape EMG AU1 X - AU2 X - AU4 X - AU6 X X AU7 X X AU9 X - AU10 - X AU12 X - AU20 X - AU23 X - AU25 X - AU27 X - AU45 - X AU46 - X TABLE 3: Facial expressivity items defined in ICRP-IEB [9] and used AUs.
Just under the ear, she places an inverted triangle in white clay, the parotid, a salivary gland and, stretching from the parotid gland to the corner of the mouth, the thin risorius muscle (Fig 8), often called the Tip stretcher', widening the mouth and creating a sardonic expression.
If you want to Google it, the major muscles used are the zygomaticus major/minor and the risorius.