What is the relationship between Cingulate Sulcus Visual Area (CSv) and Cingulate Motor Area (CMA)?

Abstract

Previous studies of the posterior cingulate sulcus have indicated a bilateral visually responsive region, named CSv, specialised for optic flow processing [Wall and Smith, 2008, Current Biology, 18, 1-4]. However, in other studies this area has also been associated with motor control and is referred to as CMA [Picard and Strick, 1996, Cerebral Cortex, 6, 342-353; Amiez and Petrides, 2012, Cerebral Cortex]. Given the spatial resolution of fMRI group results, it is not possible to be sure whether the previous reports of a visual region and a motor region in the posterior cingulate are two adjacent but separate regions, or a single ‘visuo-motor’ region. Results of our fMRI studies combining visual optic flow with motor responses tracking the direction of self-motion initially appeared to support the possibility of a single ‘visuo-motor’ region. Specifically, the visually driven activation in the posterior cingulate appeared to switch hemispheres depending on the hand used to control the joystick. However, further investigations using separate motor and visual localisers in the same participants, as well as the combined visuo-motor task, lead us to conclude that posterior cingulate contains separate motor and visual regions.