gyrus

anatomy

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June 29, 2026

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A gyrus is a convoluted ridge found between anatomical grooves, most notably on the surface of the brain. These bulges, along with the grooves called sulci, significantly increase the surface area of the cerebral cortex, the outermost layer of the brain responsible for integrating sensory information, directing motor activity, and higher intellectual functions. The cerebral cortex is divided into four main lobes: frontal, parietal, temporal, and occipital, each associated with different functions. The pattern of gyri and sulci is relatively consistent, helping to map out these distinct lobes.123

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human nervous system
Morphological development
…formations of convolutions (sulci and gyri) in the cerebral cortex and folia of the cerebellar cortex. The central and calcarine sulci are discernible by the fifth fetal month, and all major gyri and sulci are normally present by the seventh month. Many minor sulci and gyri appear after birth.
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…formations of convolutions (sulci and gyri) in the cerebral cortex and folia of the cerebellar cortex. The central and calcarine sulci are discernible by the fifth fetal month, and all major gyri and sulci are normally present by the seventh month. Many minor sulci and gyri appear after birth.
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primate
The brain
…folds and fissures (sulci and gyri) in the brain surface. The fissural pattern is seen in its simplest form in the marmosets, but in the larger New World monkeys (capuchins, for instance), the cerebrum is richly convoluted. Gyri and sulci are well marked in Old World monkeys and in the…
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…folds and fissures (sulci and gyri) in the brain surface. The fissural pattern is seen in its simplest form in the marmosets, but in the larger New World monkeys (capuchins, for instance), the cerebrum is richly convoluted. Gyri and sulci are well marked in Old World monkeys and in the…
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human nervous system
Lobes of the cerebral cortex
…convolution is known as a gyrus, and the fissure between two gyri is known as a sulcus. Sulci and gyri form a more or less constant pattern, on the basis of which the surface of each cerebral hemisphere is commonly divided into four lobes: (1) frontal, (2) parietal, (3) temporal,…
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…convolution is known as a gyrus, and the fissure between two gyri is known as a sulcus. Sulci and gyri form a more or less constant pattern, on the basis of which the surface of each cerebral hemisphere is commonly divided into four lobes: (1) frontal, (2) parietal, (3) temporal,…
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