These neural asymmetries highlight the complex progression of lifespan cognition. The authors thank Osimertinib ic50 Fruzsina Soltész for programming the colour word Stroop task. “
“The retrosplenial cortex (RSC) comprises Brodmann areas 29/30 and is
part of an extended network of brain regions engaged during fMRI studies of autobiographical memory, spatial navigation, imagining fictitious and future experiences and scene processing (Addis et al., 2007, Epstein, 2008, Epstein, 2011, Maguire, 2001a, Maguire, 2001b, Hassabis et al., 2007, Spreng et al., 2009, Svoboda et al., 2006 and Troiani et al., 2012). RSC is particularly interesting because damage that involves this region in humans can result in significant memory and navigation deficits (Aggleton, 2010, Maguire, 2001b and Vann et al., 2009), while the earliest metabolic decline in Alzheimer’s disease is centred on RSC (Minoshima et al., 1997, Nestor et al., 2003, Pengas et al., 2010 and Villain et al., 2008). Yet despite this, its precise function remains selleck chemical elusive. In a recent fMRI study by Auger, Mullally, and Maguire (2012) we offered another insight into the role of RSC. We examined different features
of items that are normally found outdoors in the everyday environment, including their size, visual salience and the permanence or stability of their location. Participants viewed images of these items one at a time, with RSC responding to only the most permanent, never moving, items. Therefore, even when complex memories, Rolziracetam navigation or scenes were not involved, a robust RSC response was evident at the level of single, permanent landmarks. We then examined participants who were good or poor navigators, and found that the latter were much less reliable at identifying the most permanent items. Moreover, when responses to the most permanent items were examined using fMRI, poor navigators had significantly reduced responses
in RSC. This suggested that the RSC’s contribution may be to provide input regarding permanent items upon which other brain areas can then build effective spatial and scene representations (Auger et al., 2012). Our previous study (Auger et al., 2012) focussed on single items; however, in the real world, we do not normally encounter items in isolation. In order to promote a proper understanding of the role of the RSC, we need to test its reaction to multiple items, as this will inform whether its responsivity is item-specific or more general. Therefore, the question we addressed here was whether RSC is simply engaged by the presence of permanence per se, irrespective of the number of permanent items being viewed, or whether is it mechanistically more nuanced, tracking the specific number of permanent items. Adjudicating between these two options is important, as going forward it could guide how we conceptualise the function of the RSC and probe the mechanisms that may operate therein.