Gestión de los procesos de enseñanza-aprendizaje

The findings of the current study show that there were, overall, very modest improvements in test scores, but with some areas of greater change, including decline in some domains. Although there was a general trend for slight

improvement, the overall picture is dominated by substantial individual variability, a feature previously noted in the literature review. This variation was evident for the entire sample, as well as within the lesion side and pathology groups. These findings are consistent with previous research. The most commonly reported finding in post-surgical paediatric epilepsy research is no significant change (approximately 70% of children, alongside decline in 10-15% and improvement in 10-15%; Moosa & Wyllie, 2017). Individual variation in this population may be one of the most consistently reported findings over the last three decades of research into cognitive outcomes (Dlugos, Moss, Duhaime, & Brooks-Kayal, 1999; Mabbott & Smith, 2003; Miranda & Smith, 2001; Sherman et al., 2011; Skirrow et al., 2019; Szabo et al., 1998). In respect of the considerable individual variation observed in the current findings, the results are broadly consistent with existing literature.

5.2.1.1 Memory

In contrast to previous research, the current study did not identify any reliable pre- to post-operative differences for the memory domains for both the LTL and RTL groups. These findings correspond to early research that has reported preserved memory functions at a similar follow-up period (Lendt et al., 1999). However the findings contrast with more recent studies which have reported that verbal memory, in particular, is vulnerable to decline following LTL surgery for epilepsy (e.g. Gleissner et al., 2002; Meekes et al., 2013; Sherman et al., 2011). It is possible that the differences are due to methodological variations (e.g. the variables included in the analyses, the measures used). It should also be noted that the relatively short follow-up period may also explain the absence of reliable difference, which will be discussed further at 5.2.3.

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Consistent with previous research conducted by Law et al. (2017), a diagnosis of MTS appeared to carry a greater risk for verbal memory decline in the current study. It has been suggested that underlying pathology represents differentiated disease processes that manifest in different cognitive outcomes for the different pathology groups (Bigel & Smith, 2001). MTS is a process of hippocampal

neuron atrophy associated with reduced hippocampal volume, whereas FCD and low-grade tumours are cortically based (Hsu, Stenberg, & Krings, 2020). A

degree of impairment in the MTS group was, therefore, not an unexpected finding, given the role of hippocampal regions in memory functions (Lee & Lee, 2013; Leritz et al., 2006; Jambaqué et al., 2007; Skirrow et al., 2015). It is

possible that the decline in verbal memory for the MTS group in the current study resulted from the primary involvement in hippocampal pathology, which was not observed in the other groups. The current study offers preliminary findings for different patterns of cognitive impairment based on underlying pathology. The individual variation observed in the memory performance in the present study, overall, was consistent with the substantial variability in post-surgical

memory performance reported by Mabbott and Smith (2003) at a similar follow-up duration to the current study. The key finding was that the children did not show uniformly poor or good performance across all tasks, instead it was noted that children did better in some tasks than others. Accordingly, this suggests post- operative memory performance is varied both within and between children following TLR. As highlighted in the literature review, the exact nature and

prevalence of memory deficits are reported to be unknown for this population due to the inconsistencies in the literature (Menlove & Reilly, 2015). Therefore, while the findings from the current study suggest an overall general trend of no reliable change in memory outcomes at one-year post-surgery, the substantial individual variability indicates that a range of outcomes can be observed.

5.2.1.2 Cognition

The current study revealed that children who undergo surgery for TLE to the LTL experienced a post-operative decline in verbal intellectual functioning based on their pre-operative performance. These findings are inconsistent with previous

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literature, which has often reported either no change or an improvement in verbal intellectual abilities for children who undergo neurosurgery to the LTL for TLE (Korkman et al., 2005; Miranda & Smith, 2001; Westerveld et al., 2000). Although the direction of change was dissimilar, the overall conclusions of prior research were supported by the present study; despite the overall positive change of surgery on cognition, the magnitude of change was small and the significant individual variation within the domain and composite scores of the current study should be noted. Although group analyses did not yield reliable change in the current study, findings revealed that while some children showed increase in verbal and non-verbal intellectual functioning, others showed decline. A decline from pre- to post-operative verbal intellectual functioning was also observed for the MTS group in the current study. This finding has not previously been reported in the literature. One possible explanation for this finding is that the hippocampus, implicated in MTS, is involved in semantic and declarative memory and has been found to relate to verbal intellectual functioning (Amat et al., 2008; Schumann et al., 2007).

5.2.1.3 Academic Attainment

In general, the current study showed no reliable pre-post differences in academic attainment, with the exception of a decline in one aspect of literacy for the tumour group. The latter finding is inconsistent with research that has reported no

significant declines in academic abilities for children with low-grade tumours one- year after surgery (García-Fernández et al., 2011). Overall, the current findings are consistent with previous research that has identified no change over time in academic attainment, such as that by Lah and Smith (2015) who found that Reading Comprehension and Spelling remained stable one year after TLR for epilepsy in children. In addition, the current findings substantiate existing research that has demonstrated significant individual variation in academic attainment (Puka et al., 2015).

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5.2.2 The Contributions of Epilepsy-Related Factors to Post-Surgical Cognitive