Master of Arts (Applied Psychology)

The main aim of this dissertation was to investigate the role of working memory in complex mental addition. Ninety upper primary school pupils completed two experiments. In the first experiment, a counting span task was used to assess the working memory capacities of the participants. In the second experiment, a series of mental addition problems were presented ( in oral and visual presentation modes ) to the participants in order to assess their mental addition speed of integer pairs and their mental addition spans.

The results from Experiment I showed that counting speed increased from P5 to P6, indicating that older participants in P6 counter faster than the younger participants in P5. The P4 and P5 were found to have an equivalent counting rate. The result also showed that counting spans were approximately the same for the three class levels. The absence of an increase in counting span with age could be a reflection of the situation with working memory for Singaporean school children in dealing with unfamiliar task. The results also revealed a linear relationship between counting span and counting speed, implying that working memory in the counting span task.

The results from Experiment 2 showed a strong correlation between oral addition span and integer addition speed, indicating that children have higher addition span when hey can perform addition faster. It was also found that visual addition span was higher than oral addition span. The result suggested that working memory have a role to play in mental addition in children. In addition, the results also supported the Baddeley and Hitch's (1974) working memory theory that the phonological-articulatory loop and the visuo-spatial scratch-pad are the two slave systems that can have an impact on the central executive of the working memory system.