The cuneus (; plural cunei) is a smaller lobe in the

occipital lobe The occipital lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The name derives from its position at the back of the head, from the Latin ''ob'', "behind", and ''caput'', "head". The occipital lobe is the vi ...

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 ve ...

. The cuneus is bounded anteriorly by 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 ...

and inferiorly by the

calcarine sulcus The calcarine sulcus (or calcarine fissure) is an anatomical landmark located at the caudal end of the medial surface of the brain of humans and other primates. Its name comes from the Latin "calcar" meaning "spur". It is very deep, and known ...

Function

The cuneus (

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 ...

) receives visual information from the same-sided superior quadrantic retina (corresponding to contralateral inferior visual field). It is most known for its involvement in basic visual processing.

Pyramidal cells Pyramidal cells, or pyramidal neurons, are a type of multipolar neuron found in areas of the brain including the cerebral cortex, the hippocampus, and the amygdala. Pyramidal neurons are the primary excitation units of the mammalian prefrontal cor ...

in the

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 ...

(or striate cortex) of the cuneus, project to

extrastriate The extrastriate cortex is the region of the occipital cortex of the mammalian brain located next to the primary visual cortex. Primary visual cortex (V1) is also named striate cortex because of its striped appearance in the microscope. The ext ...

cortices (BA 18,19). The mid-level visual processing that occurs in the extrastriate projection fields of the cuneus are modulated by extraretinal effects, like attention, working memory, and reward expectation.

Clinical research

In addition to its traditional role as a site for basic visual processing, gray matter volume in the cuneus is associated with better inhibitory control in bipolar depression patients. Pathologic gamblers have higher activity in the dorsal visual processing stream including the cuneus relative to controls.

Gallery

File:Cuneus animation small.gif, Position of cuneus(red) of left cerebral hemisphere. File:Cerebral Gyri - Medial Surface1.png, Medial surface of left cerebral hemisphere. Cuneus is visible at left in green. File:OccCaptsMedial.png, Infero-medial surface of right cerebral hemisphere. The color brown represents

. File:Slide3ZEN.JPG, Medial surface of right cerebral hemisphere. Cuneus labeled at right. File:Cuneus - DK ATLAS.png, Cuneus, shown in the right cerebral hemisphere. File:Cuneus coronal sections.gif, Cuneus highlighted in green on coronal T1 MRI images File:Cuneus sagittal sections.gif, Cuneus highlighted in green on sagittal T1 MRI images File:Cuneus transversal sections.gif, Cuneus highlighted in green on transversal T1 MRI images

References

* See p. 397 for reference to "cuneus". {{Authority control Gyri Occipital lobe Medial surface of cerebral hemisphere