- 1. [TA] Any circumscribed surface or space. 2. All of the part supplied by a given artery or nerve. 3. A part of an organ having a special function, as the motor a. of the brain. SEE ALSO: regio, region, space, spatium, zone. [L. a courtyard]- acoustic a. the floor of the lateral recess of the fourth ventricle, extending medially to the limiting sulcus and overlying the cochlear and vestibular nuclei of the rhombencephalon. SYN: a. vestibularis [TA], a. acustica.- a. acustica SYN: acoustic a..- amygdaloclaustral a. [TA] that region in the temporal lobe where lateral portions of the amygdaloid nucleus are in close apposition to, or fuse with, ventral aspects of the claustrum. SYN: a. amygdaloclaustralis [TA].- a. amygdaloclaustralis [TA] SYN: amygdaloclaustral a..- amygdalopiriform transition a. [TA] the a. where the groups of cells forming the amygdaloid nucleus are closely adjacent to the piriform cortex. SYN: a. transitionis amygdalopiriformis [TA].- anterior amygdaloid a. [TA] the most rostral portion of the amygdaloid complex composed of scattered cells representing a transition into the more distinctly organized divisions of the amygdala. SYN: a. amygdaloidea anterior [TA].- anterior hypothalamic a. the rostral portion of the hypothalamus located generally internal to the region of the optic chiasm; contains the following nuclei : anterior hypothalamic nucleus [TA] (nucleus anterior hypothalami [TA]), anterior periventricular nucleus [TA] (nucleus periventricularis ventralis [TA], interstitial nuclei of anterior hypothalamus [TA] (nuclei interstitiales hypothalami anteriores [TA]), lateral preoptic nucleus [TA] (nucleus preopticus lateralis [TA]), medial preoptic nucleus [TA] (nucleus preopticus medialis [TA]), median preoptic nucleus [TA] (nucleus preopticus medianus [TA]), paraventricular nucleus [TA] (nucleus paraventricularis hypothalami [TA]), periventricular preoptic nucleus [TA] (nucleus preopticus periventricularis [TA]), suprachiasmatic nucleus [TA] (nucleus suprachiasmaticus [TA]) and the supraoptic nucleus [TA] (nucleus supraopticus [TA]). The latter cell group consists of dorsomedial, ventromedial, and dorsolateral parts. SEE ALSO: hypothalamus. SYN: a. hypothalamica rostralis [TA], anterior hypothalamic region.- anterior intercondylar a. of tibia [TA] the broad depressed a. between the tibial condyles anteriorly to which attach the anterior ends of the menisci and the anterior cruciate ligament. SYN: a. intercondylaris anterior tibiae [TA].- aortic a. (of auscultation) the region of the chest wall over the second right costal cartilage, where sounds produced at the aortic orifice are often best heard.- bare a. of liver [TA] the a. on the posterosuperior (diaphragmatic) surface of the liver, bordered by the coronary ligament but itself devoid of peritoneum, so that the diaphragm and liver lie in direct contact and are adherent to each other. not covered by peritoneum. SYN: a. nuda hepatis [TA].- bare a. of stomach the part of posterior surface of the fundus of the stomach between the two diverging layers of the gastrophrenic ligament, that is not covered by peritoneum.- Brodmann areas areas of the cerebral cortex mapped out on the basis of the cortical cytoarchitectural patterns. See cerebral cortex.- a. of cardiac dullness a triangular a. determined by percussion of the front of the chest; it corresponds to the part of the heart that is not covered by lung tissue.- catchment a. a term relating to community mental health center which delimits the geographic a. surrounding each center, and thus the population of individuals who qualify for mental health services provided by each center.- a. cochleae [TA] SYN: cochlear a..- cochlear a. [TA] the a. inferior to the transverse crest of the fundus of the internal acoustic meatus through which the filaments of the cochlear nerve pass to enter the cochlea; forms the base of the conical modiolus about which the cochlear canal spirals. See base of modiolus of cochlea. SYN: a. cochleae [TA].- Cohnheim a. a polygonal mosaic-like figure formed by a group of myofibrils, as seen in the cross-section of a skeletal muscle fiber examined under the microscope; a shrinkage artifact of fixation. SYN: Cohnheim field.- contact a. that part of the proximal surface of a tooth which touches the adjacent tooth mesially or distally. SYN: contact point, point of proximal contact.- cribriform a. of the renal papilla [TA] the apex of a renal papilla pierced by 10–22 openings of the papillary ducts, the foramina papillaria. SYN: a. cribrosa papillae renalis [TA].- denture foundation a. that portion of the basal seat which supports the complete or partial denture base under occlusal load. SYN: basal seat, denture-bearing a., denture-supporting a., stress-bearing a. (1), supporting a. (2), tissue-bearing a..- dermatomic a. SYN: dermatome (3).- dorsal hypothalamic a. [TA] a relatively small region of the hypothalamus located ventral to the hypothalamic sulcus; contains the following nuclei : portions of the dorsomedial nucleus [TA] (nucleus dorsomedialis [TA]), endopeduncular nucleus [TA]) (nucleus endopeduncularis [TA]) and portions of the nucleus of the ansa lenticularis (nucleus ansae lenticularis [TA]). SEE ALSO: hypothalamus. SYN: a. hypothalamica dorsalis [TA], dorsal hypothalamic region.- embryonal a., embryonic a. the a. of the blastoderm on either side of, and immediately cephalic to, the primitive streak where the component cell layers have become thickened.- entorhinal a. brodmann a. 28, a cytoarchitecturally well-defined a. of multilaminate cerebral cortex on the medial aspect of the parahippocampal gyrus, immediately caudal to the olfactory cortex of the uncus; the a. is the origin of the major fiber system afferent to the hippocampus, the so-called perforant pathway.- facial nerve a. [TA] the a. of the fundus of the internal acoustic meatus superior to the transverse crest through which the facial nerve passes to enter the facial canal. SYN: a. nervi facialis [TA].- Flechsig areas three divisions (anterior, lateral, posterior) of each lateral half of the medulla as seen on transverse section, marked off by the root fibers of the hypoglossal and vagus nerves.- fronto-orbital a. SYN: orbitofrontal cortex.- gastric a. [TA] one of a number of small polygonal areas, 1–6 mm in diameter, separated by linear depressions on the surface of the mucous membrane of the stomach; they contain the gastric pits, with several gastric glands opening into each pit. SYN: a. gastrica [TA].- a. gastrica [TA] SYN: gastric a..- germinal a., a. germinativa the place in the blastoderm where the embryo begins to be formed. SYN: germinal disk.- Head areas areas of skin exhibiting reflex hyperesthesia and hyperalgesia due to visceral disease.- a. hypothalamica intermedia SYN: intermediate hypothalamic a..- inferior vestibular a. [TA] the a. of the fundus of the internal acoustic meatus inferior to the transverse crest through which the inferior portion of the vestibular (saccular) nerve passes. SYN: a. vestibularis inferior [TA].- intermediate hypothalamic a. [TA] the portion of the hypothalamus located generally internal to the region of the infundibulum; contains the following nuclei; dorsal nucleus [TA] (nucleus dorsalis hypothalami [TA]), parts of the dorsomedial nucleus [TA] (nucleus dorsomedialis [TA]), arcuate nucleus [TA] (nucleus arcuatus [TA]), posterior periventricular nucleus [TA] (nucleus periventricularis posterior [TA]), retrochiasmatic a. [TA] (a. retrochiasmatica [TA]), lateral tuberal nuclei [TA] (nuclei tuberales laterales [TA]), and the ventromedial nucleus [TA] (nucleus ventromedialis hypothalami [TA]). SEE ALSO: hypothalamus. SYN: intermediate hypothalamic region, a. hypothalamica intermedia.- Kiesselbach a. an a. on the anterior portion of the nasal septum rich in capillaries (Kiesselbach plexus) and often the seat of epistaxis. SYN: Little a..- a. of Laimer a triangular (or V-shaped) a. on the posterior aspect of the proximal esophagus, with its apex directed inferiorly in the midline and the cricopharyngeus muscle forming its base, which is an a. of weakness due to a near absence of longitudinal muscle; potential site of herniation of pharyngeal or esophageal mucosa. SYN: Laimer-Haeckerman a., V-shaped a. of esophagus.- Laimer-Haeckerman a. SYN: a. of Laimer.- lateral hypothalamic a. [TA] the portion of the hypothalamus located generally lateral to a rosterocaudal line drawn through the column of the fornix and the mammillothalamic tract; contains fibers collectively comprising the medial forebrain bundle [TA] and the following nuclei : portions of the preoptic a. [TA] (a. preoptica [TA]), portions of the lateral tuberal nuclei [TA] (nuclei tuberales laterales [TA]), the perifornical nucleus [TA] (nucleus perifornicalis [TA]), and the tuberomammillary nucleus [TA] (nucleus tuberomammillaris [TA]). SEE ALSO: hypothalamus. SYN: a. hypothalamica lateralis [TA].- mitral a. the region of the chest over the apex of the heart, where the sounds, normal or pathologic, produced at the mitral valves are usually heard most distinctly.- a. nuda hepatis [TA] SYN: bare a. of liver.- Panum a. a. in space surrounding the empirical horopter where single binocular vision is observed despite stimulation of noncorresponding retinal points. SYN: fusion a..- parastriate a. visual cortex.- a. parolfactoria [TA] SYN: parolfactory a..- parolfactory a. [TA] a small region of cerebral cortex on the medial surface of the frontal lobe, formed by the junction of the straight gyrus with the cingulate gyrus, demarcated from the subcallosal gyrus by the posterior parolfactory sulcus. SYN: a. parolfactoria [TA], Broca parolfactory a..- pear-shaped a. SYN: retromolar pad.- peristriate a. visual cortex.- posterior hypothalamic a. [TA] the portion of the hypothalamus located generally inside the region of the mammillary bodies; contains the following nuclei : dorsal premammillary nucleus [TA] (nucleus premammillaris dorsalis [TA]), lateral nucleuus of mammillary body [TA] (nucleus mammillaris medialis [TA]), supramammillary nucleus [TA] (nucleus supramammillaris [TA]_, and the ventral premammillary nucleus [TA] (nucleus premammillaris ventralis [TA]). The posterior nucleus of hypothalamus [TA] is located at the interface of intermediate and posterior hypothalamic areas and is sometimes considered a part of the latter. SEE ALSO: hypothalamus, posterior hypothalamic region. SYN: a. hypothalamica posterior [TA].- posterior intercondylar a. of tibia [TA] the deep notch between the tibial condyles posteriorly to which attaches the posterior cruciate ligament. SYN: a. intercondylaris posterior tibiae [TA].- posterior palatal seal a. the soft tissues along the junction of the hard and soft palates on which pressure within the physiologic limits of the tissues can be applied by a denture to aid in the retention of the denture. SYN: post dam a., postpalatal seal a..- a. postrema (AP) [TA] a small, elevated a. in the lateral wall of the inferior recess of the fourth ventricle; one of the few loci in the brain where the blood-brain barrier is lacking; a chemoreceptor a. associated with vomiting.- premotor a. SYN: premotor cortex.- a. preoptica [TA] SYN: preoptic region.- prestriate a. visual cortex.- pretectal a. [TA] a narrow, transversely oriented rostral zone of the mesencephalic tectum, bounded caudally by the superior colliculus, rostrally by the habenular trigone, and laterally by the pulvinar thalami; the pretectal a. contains several nuclei that receive fibers from the optic tract; it has bilateral efferent connections with the Edinger-Westphal nucleus of the oculomotor nuclear complex by way of which it mediates the pupillary light reflex. SYN: pretectal region, pretectum.- pulmonary a. the region of the chest at the second left intercostal space, where sounds produced at the pulmonary valve of the right ventricle are heard most distinctly.- relief a. in dentistry, the portion of the denture-bearing a. over which the denture base is altered to reduce functional pressure.- rest a. the portion of a tooth structure or of a restoration in a tooth that is prepared to receive the positive seating of the metallic occlusal, incisal, lingual, or cingulum rest of a removable prosthesis. SYN: rest seat.- retention a. an a. of a tooth provided during its preparation for restoration that will aid in holding the restoration in place. SEE ALSO: retention groove, retention point.- a. retrochiasmatica [TA] SYN: retrochiasmatic a.. See intermediate hypothalamic a..- secondary aortic a. region of the chest at the mid-left sternal bases where aortic diastolic murmurs are often best heard.- septal a. [TA] the region of the cerebral hemisphere that stretches as a thin sheet of brain tissue between the fornix bundle and the ventral surface of the corpus callosum, forming the medial wall of the lateral ventricle's frontal horn; it extends ventrally through the narrow interval between the anterior commissure and the rostrum of corpus collosum as the precommissural septum or subcallosal gyrus, which is continuous caudally with the preoptic a. and hypothalamus, as well as more laterally with the innominate substance; its major functional connections are with the hippocampus and hypothalamus. It is composed of a dorsal septal nucleus [TA], lateral septal nucleus [TA], medial septal nucleus [TA], septofimbrial nucleus [TA], and triangular nucleus of septum [TA]. The subformical organ [TA] is also found in this a..- silent a. any a. of the cerebrum or cerebellum in which lesions cause no definite sensory or motor symptoms.- skip areas subsidiary segments of diseased intestine or colon in regional enteritis or Crohn colitis, separated from the region of major involvement.- stress-bearing a. 1. SYN: denture foundation a.. 2. surfaces of oral structures that resist forces, strains, or pressures brought upon them during function.- a. subcallosa [TA] SYN: subcallosal gyrus.- superior vestibular a. [TA] the a. in the fundus of the internal acoustic meatus superior to the transverse crest through which the superior part of the vestibular (utriculoampullary) nerve passes to reach the macula utriculus and the ampullae of the anterior and lateral semicircular ducts. SYN: a. vestibularis superior [TA].- supporting a. 1. those areas of the maxillary and mandibular edentulous ridges which are considered best suited to carry the forces of mastication when the dentures are in function; 2. SYN: denture foundation a..- a. transitionis amygdalopiriformis [TA] SYN: amygdalopiriform transition a..- tricuspid a. the region of the chest wall over the lower part of the body of the sternum, where the sounds produced at the tricuspid valve are heard most distinctly.- vagus a. a portion of the floor of the fourth ventricle overlying the vagoglossopharyngeal nuclei.- vestibular a. [TA] the a. in the floor of the fourth ventricle lateral to the sulcus limitans [TA] and medial to the restiform body [TA] that overlies the vestibular nuclei and portions of the cochlear nuclei. SEE ALSO: inferior vestibular a., superior vestibular a..
* * *ar·ea 'ar-ē-ə, 'er- n a part of the cerebral cortex having a particular function see ASSOCIATION AREA, MOTOR AREA, SENSORY AREA
* * *ar·ea (ārґe-ə) pl. aґreae or areas [L.] 1. a limited space. 2. in anatomy, a specific surface or a region with a given function.
See also entries under region.
Medical dictionary. 2011.