| parahippocampal gyrus | A long convolution on the medial surface of the temporal lobe, forming the lower part of the fornicate gyrus, extending from behind the splenium corporis callosi forward along the dentate gyrus of the hippocampus from which it is demarcated by the hippocampal fissure. The anterior extreme of the gyrus curves back upon itself, forming the uncus, the major location of the olfactory cortex. See: entorhinal area. Synonym: gyrus parahippocampalis, hippocampal convolution, hippocampal gyrus. (05 Mar 2000) |
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| marginal gyrus | A broad convolution running in an anteroposterior direction on the medial edge of the convex surface and of each frontal lobe. Synonym: gyrus frontalis superior, marginal gyrus, superior frontal convolution. (05 Mar 2000) |
| paraterminal gyrus | A slender vertical whitish band immediately anterior to the lamina terminalis and anterior commissure; contrary to its name, it is not a cortical convolution but is the ventral continuation of the transparent septum. Synonym: area subcallosa, gyrus paraterminalis, gyrus subcallosus, pedunculus corporis callosi, corpus paraterminale, paraterminal body, paraterminal gyrus, peduncle of corpus callosum, precommissural septal area, subcallosal area, Zuckerkandl's convolution. (05 Mar 2000) |
| medial occipitotemporal gyrus | A relatively short horizontal convolution on the inferomedial aspect of the occipital and temporal lobes, demarcated from the lateral occipitotemporal or fusiform gyrus by the deep collateral sulcus, from the cuneus by the calcarine sulcus; its anterior extreme abuts the isthmus of the parahippocampal gyrus; the medial or upper strip of the gyrus forming the lower bank of the calcarine sulcus corresponds to the inferior half of the striate area or primary visual cortex and represents the contralateral upper quadrant of the binocular field of vision. Synonym: gyrus lingualis, gyrus occipitotemporalis medialis, medial occipitotemporal gyrus. (05 Mar 2000) |
| Retzius' gyrus | The intralimbic gyrus in the cortical portion of the rhinencephalon. (05 Mar 2000) |
| gyrus | One of the prominent rounded elevations that form the cerebral hemispheres, each consisting of an exposed superficial portion and a portion hidden from view in the wall and floor of the sulcus. Origin: L. Fr. G. Gyros, circle Angular gyrus, a folded convolution in the inferior parietal lobule formed by the union of the posterior ends of the superior and middle temporal gyri. Synonym: gyrus angularis, angular convolution. (05 Mar 2000) |
| gyrus angularis | angular gyrus |
| gyrus cinguli | One of the convolutions on the medial surface of the cerebral hemisphere. It surrounds the rostral part of the brain and interhemispheric commissure and forms part of the limbic system. (12 Dec 1998) |
| gyrus dentatus | Serrated strip of gray matter under the medial border of the hippocampus and in its depths. It is an archicortex which develops along the edge of the hippocampal fissure and which consists of molecular, granular, and polymorphic layers. The molecular layer is continuous with that of the hippocampus in the depths of the hippocampal fissure. (carpenter and sutin, human neuroanatomy, 8th ed, p626) (12 Dec 1998) |
| gyrus fasciolaris | A small paired band that passes around the splenium of the corpus callosum from the lateral longitudinal stria to the dentate gyrus. Synonym: gyrus fasciolaris, fascia cinerea, fasciola cinerea. (05 Mar 2000) |
| gyrus fornicatus | The horseshoe-shaped cortical convolution bordering the hilus of the cerebral hemisphere; its upper limb is formed by the cingulate gyrus, its lower by the parahippocampal gyrus. Synonym: gyrus fornicatus. (05 Mar 2000) |
| gyrus fusiformis | An extremely long convolution extending lengthwise over the inferior aspect of the temporal and occipital lobes, demarcated medially by the collateral sulcus from the lingual gyrus and the anterior part of the parahippocampal gyrus, laterally by the inferior temporal sulcus from the inferior temporal gyrus. Synonym: gyrus occipitotemporalis lateralis, gyrus fusiformis, lateral occipitotemporal gyrus, lobulus fusiformis. (05 Mar 2000) |
| gyrus lingualis | A relatively short horizontal convolution on the inferomedial aspect of the occipital and temporal lobes, demarcated from the lateral occipitotemporal or fusiform gyrus by the deep collateral sulcus, from the cuneus by the calcarine sulcus; its anterior extreme abuts the isthmus of the parahippocampal gyrus; the medial or upper strip of the gyrus forming the lower bank of the calcarine sulcus corresponds to the inferior half of the striate area or primary visual cortex and represents the contralateral upper quadrant of the binocular field of vision. Synonym: gyrus lingualis, gyrus occipitotemporalis medialis, medial occipitotemporal gyrus. (05 Mar 2000) |
| gyrus longus insulae | The most posterior and longest of the slender straight gyri that compose the insula. Synonym: gyrus longus insulae. (05 Mar 2000) |
| gyrus occipitotemporalis lateralis | An extremely long convolution extending lengthwise over the inferior aspect of the temporal and occipital lobes, demarcated medially by the collateral sulcus from the lingual gyrus and the anterior part of the parahippocampal gyrus, laterally by the inferior temporal sulcus from the inferior temporal gyrus. Synonym: gyrus occipitotemporalis lateralis, gyrus fusiformis, lateral occipitotemporal gyrus, lobulus fusiformis. (05 Mar 2000) |