14 Major Sulci

Main sulci are formed early in development
Fissures - really deep sulci

Typically Continuous Sulci

• Interhemispheric fissure
• Sylvian fissure
• Parietal-occipital fissure
• Calcarine sulcus
• Collateral sulcus
• Central sulcus

Typically Discontinuous Sulci

• Cingulate sulcus
• Precentral sulcus
• Postcentral sulcus
• Intraparietal sulcus
• Superior temporal sulcus
• Inferior temporal sulcus
• Superior frontal sulcus
• Inferior frontal sulcus

Other minor sulci are much less reliable

Image from Ono, Atlas of the Cerebral Sulci, p. 7)

Interhemispheric fissure

• hugely deep (down to corpus callosum)
• divides brain into 2 hemispheres

Sylvian fissure

• hugely deep
• mostly horizontal
• insula (purple) is buried within it
• separates temporal lobe from parietal and frontal lobes

Parietal-occipital Fissure and Calcarine Sulcus

Parietal-occipital fissure (red)

• very deep
• often Y-shaped from sagittal view
• X-shaped in horizontal and coronal views

Cuneus (pink)

• visual areas on medial side above
• calcarine (lower visual field)

Calcarine sulcus (blue)

• contains V1

Lingual gyrus (yellow)

• visual areas on medial side below calcarine and above collateral sulcus
  (upper visual field)

Collateral Sulcus

• divides lingual (yellow) and parahippocampal (green) gyri from fusiform gyrus (pink)

Cingulate Sulcus

• divides the cingulate gyrus (turquoise) from precuneus (purple) and paracentral lobule (gold)

Central, Postcentral and Precentral Sulci

Central Sulcus (red)

• usually freestanding (no intersections)
• just anterior to ascending cingulate

Precentral Sulcus (green)

• often in two parts (superior and inferior)
• intersects with superior frontal sulcus (T-junction)
• marks the anterior end of precentral gyrus (motor strip, yellow)

Postcentral Sulcus (blue)

• often in two parts (superior and inferior)
• often intersects with intraparietal sulcus
• marks posterior end of postcentral gyrus (somatosensory strip, purple)

Intraparietal Sulcus

• anterior end usually intersects with inferior postcentral (some texts call inferior postcentraltheascendingintraparietal sulcus)

• posterior end usually forms a T-junction with the transverse occipital sulcus (just posteriorto the parieto-occipital fissure)
• IPS divides the superior parietal lobule from the inferior parietal lobule (angular gyrus, gold, andsupramarginal gyrus, lime)

Slice Views

• central sulcus (red)
• precentral sulcus (green)
• transverse-occipital (purple)
• postcentral sulcus (blue)
• intraparietal sulcus (yellow)

Superior and Inferior Temporal Sulci

Superior Temporal Sulcus (red)

• divides the superior temporal gyrus (peach) from middle temporal gyrus (lime)

Inferior Temporal Sulcus (blue)

• not usually very continuous
• divides middle temporal gyrus from inferior temporal gyrus (lavender)

Superior and Inferior Frontal Sulci

Superior Frontal Sulcus (red)

• divides superior frontal gyrus (mocha) from the middle frontal gyrus (pink)

Inferior Frontal Sulcus (blue)

• divides the middle frontal gyrus from the inferior frontal gyrus (gold)

Orbital gyrus (green) and frontal pole (grey) also are shown:

Medial Frontal

• Superior frontal gyrus continues on medial side
• Frontal pole (grey) and frontal orbital gyrus (green) also shown