The cerebral hemispheres

Reading instructions
To get the most out of this learning tool, please read:
Bear, Mark F, Connors, Barry W., Paradiso, Michael A. Neuroscience : exploring the brain. - 2 ed.
Chapter 7 page 163-252

Illustrations and anmimation

Cerebral Hemispheres
The folds and convolutions of the surface of the cerebral hemispheres vastly increase the effective surface area of the brain. Each ridge is called a gyrus and each groove between ridges is called a sulcus. A deep sulcus is referred to as a fissure.

Gyri:
Precentral gyrus/gyrus precentralis: the convolution of the frontal lobe that borders posteriorly to the central sulcus and contains the primary motor area.

Postcentral gyrus/gyrus postcentralis: the convolution of the parietal lobe that borders anteriorly to the central sulcus and contains the primary sensory area.

Superior temporal gyrus/gyrus temporalis superior: the convolution of the superior temporal lobe containing the auditory cortex and language association cortex.

Angular gyrus/gyrus angularis: the convolution of the inferior parietal lobe and participates in language reception, spatial orientation and semantic representation.

Supramarginal gyrus/gyrus supramarginalis: the convolution of the inferior parietal lobe that surrounds the posterior end of the lateral fissure. This region is involved in spatial orientation and semantic representation.

Sulci:
Central sulcus/sulcus centralis: a prominent sulcus on the dorsolateral part of the cerebral hemispheres formed by the precentral and postcentral gyri. The central sulcus defines the boundary between the frontal and parietal lobes.

Precentral sulcus/sulcus precentralis: vertically oriented sulcus at the anterior margin of the precentral gyrus in the posteriuor part of the frontal lobe.

Lateral fissure/fissura lateralis: fissure on the lateral surface of the cerebral hemisphere. The lateral fissure divides the posterior frontal and anterior parietal lobes from the superior temporal lobe. Can also be called the fissure of Sylvius.

Parieto-occipital sulcus/sulcus parieto-occipitalis: vertically oriented sulcus on the medial aspect of the hemisphere. This sulcus divides the parietal and occipital lobes.