Control and maintenance processes in working memory : neuropsychological investigations

• Main Author: Moro, R.
• Published: University College London (University of London) 2008
• Subjects: 153.1
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.634599

The aim of this thesis was to investigate working memory by investigating performance on an updating task devised to pose variable demands on maintenance and control processes. The task required participants to recall information that was "relevant" according to a given criterion, at the same time inhibiting information that was not relevant to that criterion. Performance on this task was investigated in healthy participants, in order to understand the impact of different loads on maintenance and inhibition processes, and of different stimuli on recall performance and on error production. The predictions tested were that recall performance on the updating task would be affected by both load on maintenance and load on control processes and that the production of errors due to the recall of "to-be-inhibited" information would only be affected by load on control processes. The hypothesis that the central executive component of working memory would be differentially affected by normal aging, dementia of the Alzheimer's type and brain damage affecting the prefrontal lobes was also explored by investigating performance on the updating task in groups with these characteristics. The predictions were that in normal ageing maintenance would be reduced but control processes would be spared, in senile dementia both processes would be impaired and in presence of prefrontal damage only control processes would be affected. Moreover, since the multi-component model of working memory was originally conceived as the basis for complex cognitive abilities such as mental arithmetic, this was also investigated in groups of participants reported in the literature as having problems in these functions as well as in working memory. The findings are discussed in light of the predictions.