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Brain: Calcarine fissure |
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Medial surface of left cerebral hemisphere. ("Calcarine fissure" visible at left.) |
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Coronal section through posterior cornua of lateral ventricle. (Label for "Calcarine fissure" visible at bottom. |
Latin |
fissura calcarina |
Gray's |
subject #189 820 |
Part of |
Occipital lobe |
NeuroNames |
hier-25 |
The calcarine fissure (or calcarine sulcus) is an anatomical landmark located at the very caudal end of the medial surface of the brain. It begins near the occipital pole in two converging rami and runs forward to a point a little below the splenium of the corpus callosum, where it is joined at an acute angle by the medial part of the parietooccipital fissure. The anterior part of this fissure gives rise to the prominence of the calcar avis in the posterior cornu of the lateral ventricle.
The calcarine sulcus is where the primary visual cortex is concentrated. The central visual field is located in posterior portion of the calcarine sulcus and the peripheral visual field in the anterior portion. It is interesting to note, though unsurprising, that the amount of cortex dedicated to each square millimeter of the visual field is highly non-proportional; significantly more cortex is dedicated to the processing of information originating from the fovea than other locations.[1]
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Brain: telencephalon (cerebrum, cerebral cortex, cerebral hemispheres) |
primary sulci/fissures |
medial longitudinal, lateral, central, parietoöccipital, calcarine, cingulate |
frontal lobe |
precentral gyrus (primary motor cortex, 4), precentral sulcus, superior frontal gyrus (6, 8), middle frontal gyrus (46), inferior frontal gyrus (Broca's area, 44-pars opercularis, 45-pars triangularis), prefrontal cortex (orbitofrontal cortex, 9, 10, 11, 12, 47) |
parietal lobe |
postcentral sulcus, postcentral gyrus (1, 2, 3, 43), superior parietal lobule (5), inferior parietal lobule (39-angular gyrus, 40), precuneus (7), intraparietal sulcus |
occipital lobe |
primary visual cortex (17), cuneus, lingual gyrus, 18, 19 (18 and 19 span whole lobe) |
temporal lobe |
transverse temporal gyrus (41-42-primary auditory cortex), superior temporal gyrus (38, 22-Wernicke's area), middle temporal gyrus (21), inferior temporal gyrus (20), fusiform gyrus (36, 37) |
limbic lobe/fornicate gyrus |
cingulate cortex/cingulate gyrus, anterior cingulate (24, 32, 33), posterior cingulate (23, 31),
isthmus (26, 29, 30), parahippocampal gyrus (piriform cortex, 25, 27, 35), entorhinal cortex (28, 34) |
subcortical/insular cortex |
rhinencephalon, olfactory bulb, olfactory tract, corpus callosum (splenium, genu, rostrum), lateral ventricles, septum pellucidum, ependyma, internal capsule, corona radiata, external capsule, fornix (commissure of fornix), anterior commissure, posterior commissure |
hippocampal formation |
dentate gyrus, hippocampus, subiculum |
basal ganglia |
striatum (caudate nucleus, putamen), lentiform nucleus (putamen, globus pallidus), claustrum, extreme capsule, amygdala, nucleus accumbens |
Some categorizations are approximations, and some Brodmann areas span gyri. |