Accelerated Long-term Forgetting in Children with Epilepsy: An Investigation of the Temporal Trajectory and Contribution of Executive Skills

Abstract

In individuals with epilepsy, the most common clinical complaint relates to memory failure. Memory impairments have particularly detrimental impacts on the developing child, resulting in failure to acquire skills and a slower rate of academic and social progression. Thus, early detection of memory problems in children is imperative for early intervention. Nevertheless, gauging the memory difficulties in clinical practice is inherently problematic: memory performance on standardised neuropsychological tests is often discrepant with subjective reports from the child with epilepsy and their caregiver. Standardised assessments of long-term memory are confounded by measurement shortcomings, including ecological validity, developmental appropriateness, and temporal sensitivity. The most problematic of these is perhaps the brevity of recall delays used, which are typically 2 to 30 minutes. The process of memory consolidation exceeds this, rendering these tests insensitive to the subsequent memory deterioration experienced by these children. In recent decades, a memory phenomenon uncaptured by standardised episodic memory tests has been documented in patients with epilepsy: accelerated long-term forgetting (ALF). ALF is characterised by the rapid deterioration of memory that occurs during the process of memory consolidation, irrespective of intact initial learning and recall. Research has established that children with epilepsy also show differential patterns of memory deterioration over extended delays (i.e., days or weeks) relative to typically developing children. The aims of this thesis were to (i) investigate the temporal pattern of ALF in children with genetic generalised epilepsy (GGE) and temporal lobe epilepsy (TLE), (ii) determine if ALF is present in both verbal and visual materials, (iii) examine the contribution of executive skills for the presence of ALF, and (iv) review the current state of evidence for memory rehabilitation in this clinical population.