chiasm


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chiasm

 [ki´azm]
a decussation or X-shaped crossing.
optic chiasm a structure in the forebrain formed by the decussation of fibers of the optic nerve from each half of each retina.

chi·asm

(kī'azm),
1. An intersection or crossing of two lines.
2. In anatomy, a decussation or crossing of two fibrous bundles, such as tendons, nerves, or tracts.
3. In cytogenetics, the site at which two homologous chromosomes make contact (thus appearing to be crossed), enabling the exchange of genetic material during the prophase stage of meiosis.
Synonym(s): chiasma [TA]
[G. chiasma]

chiasm

/chi·asm/ (ki´azm) a decussation or X-shaped crossing.
optic chiasm  the structure in the forebrain formed by the decussation of the fibers of the optic nerve from each half of each retina.

chiasm

[kī′azəm]
Etymology: Gk, chiasma, lines that cross
1 the crossing of two lines or tracts, as of the optic nerves at the optic chiasm.
2 (in genetics) the crossing of two chromatids in the prophase of meiosis. chiasmal, chiasmic, adj.

chi·asm

(kīazm)
1. An intersection or crossing of two lines.
2. anatomy a decussation or crossing of two fibrous bundles, such as tendons, nerves, or tracts.
Synonym(s): chiasma.
3. cytogenetics the site at which two homologous chromosomes make contact (thus appearing to be crossed), enabling the exchange of genetic material during the prophase stage of meiosis.
Synonym(s): Budd syndrome.
[G. chiasma]

chi·asm

, chiasma (kīazm, kī-azmă)
In anatomy, decussation or crossing of two fibrous bundles, such as tendons, nerves, or tracts.
[G. chiasma]

chiasm

a decussation or Y-shaped crossing.

optic chiasm
a structure in the forebrain formed by the decussation of fibers of the optic nerve from each half of each retina.
References in periodicals archive ?
In "Spring Pools," it's the self-enclosing figure of chiasm (flowery waters, watery flowers) that tries to hold back the inevitable flow.
The binasal field defects could be due to a defect in the normal sorting and segregation of retinal ganglion axon populations that decussate and those that remain ipsilateral upon entering the optic chiasm from the optic nerves.
Despite the adherence of lesion to the optic chiasm and cavernous sinus in this case, there was no neuro-opthalmological sign detected in physical examination.
The outline of the psalm thus forms a perfect chiasm.
The coalescence of multiple granulomas in the brain parenchyma can produce space-occupying lesions, most commonly in the optic chiasm, floor of the third ventricle, and pituitary stalk, but can occur anywhere in the CNS.
When abnormalities of the pituitary gland are visible, CT may reveal expansion and hyperdensity of the gland, which may be accompanied by mass effect on the suprasellar structures, including the optic chiasm (Figure 5).
The wounded body, for instance, stands at the heart of Lara Buxbaum's essay on Marlene van Niekerk, but it features in supplementary contexts in the rape and disfigurement of Lourdes Puente (in Inger Pettersson's article), in the maiming and killing of the Pequots (in David Watson's article), in the fascination with erotically mutilated bodies (in John Masterson's article), and in the chiasm or "intertwining" of the perceiver with the perceived world that forms a central tenet of Merle Williams's understanding of Absalom, Absalom
Indeed, the central image of stanza four--a punning conceit of hands on [clock-]hands--plays ironically around the potential for a reciprocity of touch and touched in a manner that was later to become central to Merleau-Ponty's work in the celebrated "reversibility thesis"--the image of the thinker's two hands touching one another, used to explore the relationship between touch and touching ("The Intertwining-The Chiasm," p.
Research objectives and content The Drosophila irregular chiasm C - roughest (irreC-rst) gene encodes a member of the DM-GRASP subgroup of the neural cell adhesion molecules of the immunoglobulin superfamily.
Also underpinning the argument here is the work of Maurice Merleau-Ponty, who offers "uncontested evidence that one must see or feel in order to think, that every thought known to us occurs to a flesh'" and whose insistence on the figure of "intertwining" or the chiasm, to define embodied experience proves highly suggestive for Knapp's close readings of Spenser and Shakespeare.
There were heterogeneous parenchymal areas and cystic degeneration in the central and the optic chiasm displaced to the cranium.
And that difference is the basis of egoanalysis, for whether awareness of the body as such, or acknowledging the difference or chiasm between 'myself' and an 'other,' a phenomenological account of the "remainder" brings the ego to face the mystery of itself as both in the world and outside it.