Dados do Trabalho

Título

Influence of the natural history of temporal lesions on verbal episodic memory performance

Introdução

Temporal lobe epilepsy (TLE) is the most common type of focal epilepsy, followed by other types of lesions (tumors and cavernous malformation, for instance), with a higher incidence of refractory seizures that, in many cases, present with childhood onset. This neurological disorder brings with it progressive structural and cognitive losses over time, being episodic memory one of the most affected cognitive domains. Therefore, evaluating cognitive functioning helps to identify possible mnemonic impairments, their dissociation among other abilities, the impact on functionality, the planning of interventions, and surgical decisions.

Objetivo

Aiming to verify the influence of the natural history of temporal lesions on memory, this study analyzed the performance in verbal episodic memory tasks in adult patients with TLE who were candidates for neurosurgery.

Método

Included were 23 right-handed patients (16 [69,6%] male, age 21 ± 60 years) diagnosed with temporal lobe epilepsy associated with structural lesions (14 [60,9%] mesial temporal sclerosis, 9 [39,1%] tumors; 8 [34,8%] on the right and 15[65,2%] on the left side). Patients with IQ < 80 were excluded. To assess episodic verbal memory performance, the free and cued selective reminding test [TESLIP, from Paz Fonseca, Zimmermann e Delaere, 2019 in Portuguese] was used. Statistical analyses were performed on SPSS 20.

Resultados

The median age of epilepsy onset was 20,9 years (range, 1 – 57). The mean free delayed recall (FDR) z-score was -5,27 ± 1,07. Lower age of epilepsy onset was associated with poorer FDR performance (ρ = .539, P = .010), but not with lesion type or side. However, a multiple regression analysis model revealed that lesion laterality exerts the most significant effect upon FDR when corrected for the effect age of onset and lesion type (β = -1.561, P = .002), with left-sided lesions associated with lower scores.

Conclusão

The results reveal that the earlier the onset of epileptic seizures, the greater the losses in long-term encoding of verbal information over the years, especially in patients with left-sided lesions. Thus, factors such as earlier seizure onset and the location and laterality of the lesion, especially when associated with limited clinical evaluation and diagnostic resources, may imply in structural, cognitive losses that affect the quality of life and functionality of the patient with TLE.

Palavras-chave

neuropsychology, temporal lobe epilepsy; natural history; earlier epileptic seizures