The precuneus (or Foville's quadrilateral lobule) is a gyrus on the inner side of the parietal lobe of the cerebral cortex. It is limited forward by the calloso-marginal groove and behind by the parieto-occipital groove. Its lower limit is the sub-parietal groove that extends the cingulate groove along a curve parallel to the corpus callosum. The part of the cortex between the paracentral sulcus (in front) and the calloso-marginal sulcus (below and behind) is the paracentral lobule, extending on the inner side the postcentral gyrus.

The precuneus is composed of two convolutions, anterior and posterior, separated by a vertical furrow more or less deep, called transverse parietal furrow. change the code

Olivier Houdé, Bernard Mazoyer, Nathalie Tzourio-Mazoyet, Brain and Psychology Introduction to anatomical and functional brain imaging, puf, 2002

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