Modelling working memory through attentional mechanisms

Recent studies of working memory have shown that the network of brain areas that supports working memory function overlaps heavily with the well studied network of selective attention. It has thus been suggested that working memory may operate by means of a repeated focusing of attention on the internal representations of the items that need to be maintained. We have employed our CODAM model of attention to simulate a specific working memory paradigm based on precisely this concept of 'refreshing' internal representations using attention. We propose here that the well known capacity limit of working memory can be attributed to the 'scarceness' of attentional resources. The specific mechanism of CODAM for modelling such scarceness is used in the paradigm to explain the behavioural and brain imaging data. This and related paradigms allow us to extend the specification of CODAM sites and functions to more detailed executive functions under executive control.