The volume of grey matter was reduced in the right inferior parietal lobule and the left middle, inferior and precentral gyri.
Cuts were made along the crests of gyri and the depths of sulci.
The brain at 24-week gestation has no sulci or gyri except for the clefts separating the major hemispheres and lobes.
For all languages, activations were primarily observed in the left prefrontal cortex, in particular in the inferior frontal, middle frontal and precentral gyri.
Labeled in the figure of the human brain are the two regions of the parietal lobe unique to humans, the supramarginal and angular gyri.
This suggests that the posterior supramarginal gyri are more involved in vocabulary than either comprehension or fluency.
Each normal control subject showed the most robust activation cluster in the pre- and postcentral gyri along the central sulcus.
A mean of 60% of the cor tical sheet was occupied by gyri in the macaque.
