Rich club “chronoarchitecture” forms the neural basis for the processing of hierarchical stimuli
contact: Falko Mecklenbrauck
Not only the world around us consist of a multitude of nested and non-nested hierarchical structures, but also our brain can be described in the ways of structural and functional hierarchies. Thus, it has been theorized that the neural processing of hierarchical stimuli also behaves in a hierarchical manner. Evidence from cytoarchitectural and frequency analysis studies as well as various theories of frontal lobe functions proposed an anterior-posterior hierarchy of processing steps (e.g. Badre & Nee, 2018). However, the question remains, which organizational principle structures the stimuli hierarchically. A promising approach we want to focus on in project is the temporal persistence of stimuli. Areas near the top of the hierarchy are able to integrate and maintain information over a longer span of time (Koechlin & Summerfield, 2007). The structural backbone of this temporal hierarchy might be constructed by the rich club organization of the cerebral network. Following this idea, hierarchically higher thus more stable processing near a rich club hub and hierarchically lower, more transient processing closer to more peripheral nodes, could build an axis of “chronoarchitecture” (Gollo et al., 2015) which possibly offers a very general theory of information processing. Therefore, we will combine function magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI) and graph theoretical analyses to connect the functional processes to the network architecture. In the first experiment, the participants will be presented sequences of numbers, that contain hierarchical structures of different level and length. This paradigm will be applied to determine “temporal receptive windows” (Hasson et al., 2008) of different cortical areas which will then be mapped onto the furthermore identified structural network to address relation of hierarchical stimuli, their temporal persistence, and the underlying neural organization.