Developmental Pathways in the Assimilation of Non-geometric Information for Orientation in Children: a Neurorobotic Model

The performance of children in an orientation task involving geometric and nongeometric spatial cues presents an interesting pathway during development. At an early stage, children are able to exploit the first, but do not use the information provided by the second. This surprising result has been interpreted resorting to the presence of a geometric module in vertebrates’ brain whose limitation can be overcome with the acquisition of language (Hermer and Spelke, 1996). But the described set of results is not always verified: Learmonth and colleagues (2001, 2002) have shown that children, under certain conditions, can use the information provided by landmarks. In accordance with what has been suggested in the cited study by Learmonth (2001), a crucial factor to allow the use of non-geometric information is the stability of the cue presence. In the present work we have tried to address this question training artificial organisms, namely simulated robots, to solve the two tasks. Results show that if the nongeometric features is always present in the training procedure, the artificial organisms can use them to orient. Nonetheless, if the non-geometric information is present only for a certain period of the training, the percentage of artificial organisms that can exploit this information source varies proportionally to the length of exposure to non-geometric features. Manipulating this variable, it has also been possible to observe different developmental pathways and, under certain conditions, to reproduce the developmental pattern observed in children.