In Search of a Neural Model for Serial Order: A Brain Theory for Memory Development and Higher Level Cognition

In order to keep trace of information and grow up, the infant brain has to resolve the problem about where old information is located and how to index new ones. We propose that the immature prefrontal cortex (PFC) uses its primary functionality of detecting hierarchical patterns in temporal signals as a second feature to organize the spatial ordering of the cortical networks in the developing brain itself. Our hypothesis is that the PFC detects the hierarchical structure in temporal sequences in the shape of ordinal patterns and uses them to index information hierarchically in different parts of the brain. Henceforth, we propose that this mechanism for detecting ordinal patterns participates also in the hierarchical organization of the brain during development; i.e., the bootstrapping of the connectome. By doing so, it gives the tools to the language-ready brain for manipulating abstract knowledge and for planning temporally ordered information; i.e., the emergence of causality and symbolic thinking. In this position paper, we will review several neural models from the literature that support serial ordering and propose an original one. We will confront then our ideas with evidence from developmental, behavioral, and brain results.