Abstracts

Rationale: Executive functions are essential for good information encoding and storing as well as to mental organization. Therefore, it is reasonable to postulate that executive dysfunction (ED) may aggravate memory impairments. Memory deficits are well-established in patients with temporal lobe epilepsy (TLE). ED have also been demonstrated in these patients. However, the relationship between ED and visual and verbal memory have not been investigated yet. We aimed to characterize memory and executive functioning in children with TLE and to evaluate the impact of ED in memory tasks. Methods: For this purpose, we evaluated 36 children and adolescents (11.78 years-old; SD 2.26) with TLE and 28 healthy volunteers (11.96 years-old; SD 2.30) using a comprehensive battery composed of tests of episodic and semantic memory, learning, attention (concentration, selective and divided attention), mental flexibility and, mental tracking. Four analyses were conducted: (i) comparison between patients and controls in memory tests; (ii) comparison between patients and controls in executive functions tests; (iii) correlation between memory and executive functions tests and, (iv) comparison between patients with mild/moderate ED and severe ED in memory tests. Results: Children with TLE had worse performance in immediate (p=0.046) and delayed (p=0.048) Story Memory and in Sentence Memory (p=0.002). As to executive functions, patients showed impairments in Trail Making B errors (p=0.016); WCST categories achieved (p=0.018) and number of non-perseverative responses (p=0.046); Verbal Fluency (p=0.048) and Number and Letter (p=0.005). Planning, abstraction and mental tracking were not correlated to memory tasks. All attention domains and working memory were correlated with visual and verbal memory. Patients with severe ED had worse performance in Scenes Memory (p=0.032); Design Memory (p<0.001); immediate (p=0.002) and delayed Story Memory (p=0.003); Sentence Memory (p<0.001); Verbal (p=0.010) and Visual (p=0.048) Learning. Conclusions: Children and adolescents with TLE have memory and executive dysfunctions. Moreover, there is an impact of ED in the performance of memory tests, that could be demonstrated both with the correlation of memory and executive functions tests and with the worse performance of patients with severe ED in memory tests. Therefore, clinicians should be aware that evaluation and rehabilitation programs for memory in patients with TLE must take into consideration executive functions.