MEMORY AND METAMEMORY IN PATIENTS WITH TEMPORAL LOBE EPILEPSY

Abstract

It is well established that patients with temporal lobe epilepsy (TLE) commonly report memory difficulties. The aim of this thesis was to use a novel approach adopting Nelson & Narens' (1990) theoretical framework to investigate whether metacognitive knowledge and memory performance were differentially disrupted in patients with TLE. More specifically, investigating to what extent poor memory in TLE could result from inadequate metamemory monitoring, inadequate metamemory control or both. Experiment I employed a combined Judgement-of-Learning and Feeling-of-Knowing task to investigate whether participants could monitor their memory successfully at both the item-by-item and global levels. The results revealed a dissociation between memory and metamemory in TLE patients. TLE patients presented with a clear episodic memory deficit compared with controls yet preserved metamemory abilities. Experiments 2 and 3 explored the sensitivity approach to examine metacognitive processes that operate during encoding in TLE patients and controls. Both these experiments demonstrated that TLE patients were sensitive to monitoring and control processes at encoding. The final experiment further investigated memory performance by examining the role of lateralisation of the seizure focus using material specific information and the 'Remember-Know' paradigm. The findings from the verbal task provided partial support to the material-specific hypothesis. The results from these experiments are discussed in terms of their association with executive functioning and memory deficits in TLE, and have important implications for future research examining memory and metamemory in TLE patients and other clinical populations.