Short English equivalent

Libelle of note

See note # 9188

The Insula is composed of three Belt regions (see Mesulam M-M and Mufson EJ (1985 The insula of Reil in man and monkey. Architectonics, connectivity and function. In: Peters A, Jones EG, eds, Cerebral Cortex, Vol 4, Plenum Press, New York, pp 179-226): 1) The Cortex insularis agranularis (Agranular insular cortex, where Layers II and IV are lacking) in the Anterior insula is characterized by a Superficial pyramidal layer and an Inner cell layer, continuous with the Pyramidal layer of the Piriform cortex. Here, the recently rediscovered von Economo neurons (VENs) are found (see Allman JM, Tetreault NA, Hakeem AY, et al. 2011 The von Economo neurons in fronto-insular and anterior cingulate cortex. Ann NY Acad Sci 1225:59-71). 2) The Cortex insularis dysgranularis (Dysgranular insular cortex), a Proisocortical region characterized by the presence of an inconspicuous Inner granular layer IV. Layers V and VI are also not as clearly separated from each other as in true isocortex. 3) The Cortex insularis granularis (Granular insular cortex), a posterior granular region with clearly visible Inner (layer IV) and Outer (layer II) granular layers (True isocortex; see also Zilles and Amunts 2012).