Superior Parietal Lobule (SPL)

The posterior parietal cortex, in turn, is divided into superior (SPL) and inferior (IPL) parietal lobules, separated by the intraparietal sulcus. According to Brodmann (1909), the superior parietal lobule, the target of the present chapter, hosts two cytoarchitectonic fields, area 5 anteriorly and area 7 posteriorly. In the human brain, area 5 is a quite restricted area while area 7 occupies most of the SPL (see close-up in Fig. 1a). In the macaque brain, instead, area 5 occupies most of the SPL and area 7 only a restricted region of cortex in the caudalmost part of SPL (see close-up in Fig. 1b). Several studies in the last century claimed that this latter cortical region is not area 7, as originally indicated by Brodmann, but a variation of area 5. In either cases, it remains that the cytoarchitecture in SPL is not uniform, and the different architectural patterns of anterior and posterior parts of SPL suggest that they host different functional properties and subserve different functional roles.The following is a summary of the functional properties, anatomical connections, and possiblefunctional roles of SPL. The description refers to the macaque SPL, which has been intensively studied in the last decades. The human SPL has been much less studied to date and has not been taken into account here.