The calcarine sulcus (or calcarine fissure) is an anatomical landmark located at the caudal end of the medial surface of the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...

of humans and other

primates Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians (monkeys and apes, the latter including huma ...

. Its name comes from the Latin "calcar" meaning "spur". It is very deep, and known as a complete sulcus.

Structure

The calcarine sulcus begins near the

occipital pole The vertebrate cerebrum (brain) is formed by two cerebral hemispheres that are separated by a groove, the longitudinal fissure. The brain can thus be described as being divided into left and right cerebral hemispheres. Each of these hemispheres ...

in two converging rami. It runs forward to a point a little below the

splenium of the corpus callosum The corpus callosum (Latin for "tough body"), also callosal commissure, is a wide, thick nerve tract, consisting of a flat bundle of commissural fibers, beneath the cerebral cortex in the brain. The corpus callosum is only found in placental m ...

. Here, it is joined at an acute angle by the medial part of the

parieto-occipital sulcus In neuroanatomy, the parieto-occipital sulcus (also called the parieto-occipital fissure) is a deep sulcus in the cerebral cortex that marks the boundary between the cuneus and precuneus, and also between the parietal and occipital lobes. Only ...

. The anterior part of this sulcus gives rise to the prominence of the

calcar avis The calcar avis, previously known as the hippocampus minor, is an involution of the wall of the lateral ventricle's posterior cornu produced by the calcarine fissure. It is sometimes visible on ultrasonogram and can resemble a clot. Name The ri ...

in the posterior cornu of the

lateral ventricle The lateral ventricles are the two largest ventricular system, ventricles of the brain and contain cerebrospinal fluid (CSF). Each cerebral hemisphere contains a lateral ventricle, known as the left or right ventricle, respectively. Each lateral ...

. The

cuneus The cuneus (; plural cunei) is a smaller lobe in the occipital lobe of the brain. The cuneus is bounded anteriorly by the parieto-occipital sulcus and inferiorly by the calcarine sulcus. Function The cuneus (Brodmann area 17) receives visua ...

is above the calcarine sulcus, while the

lingual gyrus The lingual gyrus, also known as the ''medial'' occipitotemporal gyrus, is a brain structure that is linked to processing vision, especially related to letters. It is thought to also play a role in analysis of logical conditions (i.e., logical ord ...

is below it.

Development

In humans, the calcarine sulcus usually becomes visible between 20 weeks and 28 weeks of

gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregna ...

Function

The calcarine sulcus is associated with

visual cortex The visual cortex of the brain is the area of the cerebral cortex that processes visual information. It is located in the occipital lobe. Sensory input originating from the eyes travels through the lateral geniculate nucleus in the thalamus and ...

. It is where the

primary visual cortex The visual cortex of the brain is the area of the cerebral cortex that processes visual information. It is located in the occipital lobe. Sensory input originating from the eyes travels through the lateral geniculate nucleus in the thalamus and ...

(V1) is concentrated. The central visual field is located in the posterior portion of the calcarine sulcus, and the peripheral visual field is located in the anterior portion.

History

The name of the calcarine sulcus comes from the Latin "calcar" meaning "spur".

Additional images

File:Calcarine sulcus animation small.gif, Position of calcarine sulcus (shown in red). File:Calcarine sulcus medial.jpg, Calcarine fissure (shown in red). File:Brodmann Cytoarchitectonics 17.png, Calcarine sulcus highlighted in

Brodmann Area 17 The visual cortex of the brain is the area of the cerebral cortex that processes visual information. It is located in the occipital lobe. Sensory input originating from the eyes travels through the lateral geniculate nucleus in the thalamus and ...

, Lateral and Medial views. File:Medial surface of cerebral cortex - gyri.png, Medial surface of cerebral cortex - gyri

References

External links

* * https://web.archive.org/web/20090310124713/http://www2.umdnj.edu/~neuro/studyaid/Practical2000/Q31.htm * - "The Visual Pathway from Below"
NIF Search - Calcarine Fissure
via the

Neuroscience Information Framework The Neuroscience Information Framework is a repository of global neuroscience web resources, including experimental, clinical, and translational neuroscience databases, knowledge bases, atlases, and genetic/ genomic resources and provides many aut ...

{{Authority control Sulci (neuroanatomy) Medial surface of cerebral hemisphere Occipital lobe Anatomic Landmarks