parahippocampal gyrus


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gyrus

 [ji´rus] (pl. gy´ri) (L.)
one of the many convolutions of the surface of the cerebral hemispheres caused by infolding of the cortex, separated by fissures or sulci; called also cerebral gyrus.
angular gyrus one continuous anteriorly with the supramarginal gyrus.
annectent gyri various small folds on the cerebral surface that are too inconstant to bear specific names; called also gyri transitivi.
Broca's gyrus inferior frontal gyrus.
central gyrus, anterior precentral gyrus.
central gyrus, posterior postcentral gyrus.
cerebral gyrus gyrus.
Cerebral gyri. From Applegate, 1996.
cingulate gyrus (gyrus cin´guli) an arch-shaped convolution situated just above the corpus callosum.
frontal gyrus any of the three (inferior, middle, and superior) gyri of the frontal lobe.
fusiform gyrus one on the inferior surface of the hemisphere between the inferior temporal and parahippocampal gyri, consisting of a lateral (lateral occipitotemporal gyrus) and a medial (medial occipitotemporal gyrus) part.
hippocampal gyrus (gyrus hippocam´pi) one on the inferior surface of each cerebral hemisphere, lying between the hippocampal and collateral fissures; called also parahippocampal gyrus.
infracalcarine gyrus (lingual gyrus) one on the occipital lobe that forms the inferior lip of the calcerine sulcus and, together with the cuneus, the visual cortex.
marginal gyrus the middle frontal gyrus.
occipital gyrus any of the three (superior, middle, and inferior) gyri of the occipital lobe.
occipitotemporal gyrus, lateral the lateral portion of the fusiform gyrus.
occipitotemporal gyrus, medial the medial portion of the fusiform gyrus.
orbital gyri irregular gyri on the orbital surface of the frontal lobe.
parahippocampal gyrus hippocampal gyrus.
paraterminal gyrus a thin sheet of gray matter in front of and ventral to the genu of the corpus callosum.
postcentral gyrus the convolution of the frontal lobe immediately behind the central sulcus; the primary sensory area of the cerebral cortex; called also posterior central gyrus.
precentral gyrus the convolution of the frontal lobe immediately in front of the central sulcus; the primary motor area of the cerebral cortex; called also anterior central gyrus.
gyrus rec´tus a cerebral convolution on the orbital aspect of the frontal lobe.
supramarginal gyrus that part of the inferior parietal convolution which curves around the upper end of the fissure of Sylvius.
temporal gyrus any of the gyri of the temporal lobe, including inferior, middle, superior, and transverse temporal gyri; the more prominent of the latter (anterior transverse temporal gyrus) represents the cortical center for hearing.
gy´ri transiti´vi annectent gyri.
uncinate gyrus the uncus.

par·a·hip·po·cam·pal gy·rus

[TA]
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 on itself, forming the uncus, the major location of the olfactory cortex.
See also: entorhinal area.

parahippocampal gyrus

a convolution on the inferior surface of each cerebral hemisphere, lying between the hippocampal and collateral sulci.

par·a·hip·po·cam·pal gy·rus

(par'ă-hip'ō-kam'păl jī'rŭs) [TA]
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 on itself, forming the uncus, the major location of the olfactory cortex.
References in periodicals archive ?
As anticipated, there were activations in the left PFMG, an area associated with word retrieval, and in the left lingual gyrus, the left parahippocampal gyrus and the left PCC, areas related to spatial cognition.
The results found in the parahippocampal gyrus can relate to the activation observed when a person is exposed to information on places such as rooms, maps, cities and landscapes (Aguirre, Detre, Alsop, & D'Esposito, 1996).
Fan and colleagues [96] studied the functional connection of the vetromedial prefrontal cortex (vMPFC) in patients with schizophrenia; they found (a) decreased functional connection between the vMPFC and the medial frontal lobe, right middle temporal gyrus, right hippocampus, parahippocampal gyrus and amygdale, (b) decreased strength of the negative correlation between the vMPFC and the bilateral DLPFC and anterior supplementary motor area, and (c) a positive correlation between the reduction in the vMPFC-DLPFC connection and the positive symptoms of schizophrenia.
Their gray matter volume was also smaller in the right hippocampus and parahippocampal gyrus compared to their unaffected siblings.
What surprised us, though, is that when other people's behavior aroused suspicion, the parahippocampal gyrus lit up, acting like an inborn lie detector.
The more uncertain a seller was about a buyer's credibility," Montague said, "the more active his or her parahippocampal gyrus became.
What surprised us, though, is that when other people's behaviour aroused suspicion, the parahippocampal gyrus lit up, acting like an inborn lie detector," he explained.
Combining structural MRI and fMRI, Ye and colleagues [27] were the first to document decreased density of the right dorsolateral prefrontal grey matter among patients with depression; they also observed decreased FC between the right dorsolateral prefrontal cortex and right parietal lobe and increased FC between the right dorsolateral prefrontal cortex and the left dorsal cingulate cortex, left parahippocampal gyrus, thalamus and precentral gyrus.
Male OCD patients responded to sexual pictures with more activation in the posterior cingulate cortex, parahippocampal gyrus, and right cingulate gyrus, indicating "higher visual imagination and more personal relevance," compared to controls, she said.
The studies have also reported structural changes in the temporoparietal lobes, the occipital lobe, the insula lobe, the cerebellum, the anterior limb of the internal capsule, the corpus callosum, the parahippocampal gyrus, and the midbrain.
19] In a subsequent study, [21] the same research team assessed a sample of patients with intractable OCD and found increased glucose metabolism in several brain regions: left cingulate gyrus, gray matter in the superior frontal gyrus, gray and white matter in the middle frontal gyrus, white matter in the inferior frontal gyrus, white matter outside the putamen, white matter in the anterior commissure of the limbic lobe, parahippocampal gyrus, dorsomedial nucleus of the thalamus, and amygdale.
Women's rCBF decreased in visual areas, including the fusiform gyrus and occipital cortex, right amygdala, and an area extending from the cerebellum into the adjoining right parahippocampal gyrus.