Developmental Change in a Spatial Task of Attentional Capacity: An Essay Toward an Integration of Two Working Memory Models

The objective of this paper is to illustrate the complementarity of two lines of studies on Working Memory, the neo-Piagetian models of Pascual-Leone and Case on the one hand, and Baddeley's model, on the other. After a brief summary of each model, their similarities and differences are reviewed. An empirical longitudinal study is then presented as an illustration. Four cohorts of children, aged 5, 6, 8, and 10 years on the first assessment, were examined once a year over five years, with a short-term memory task (Mr Peanut), asking for the recall of the location of coloured spots in a clown figure. Two versions were used: a unicoloured task (Peanut-P) and a multicoloured task (Peanut-C), in which subjects had to recall both positions and colours. Three aspects of the results are emphasised. First, it was found that performances in Peanut-C increased with item complexity up to a certain level, beyond which they tended to remain stable; this stability was interpreted as reflecting the limits in processing resources which are postulated by neo-Piagetian models. Secondly, a drastic diminution in the performances was observed on the fourth year, corresponding to a change in the way of responding: The task was computerised, and subjects had to answer, using a computer mouse. It is argued that the monitoring of the mouse disrupts performances because it draws on the same limited resources as the memory task. Finally, results showed that the monitoring of the mouse interferes more with the recall of positions than with the recall of colours, as could be expected if monitoring a computer mouse represents a spatial interference task. Methodological drawbacks of the studies are also discussed, and suggestions for further research indicated.