Visual working memory in primary generalized epilepsy

Abstract

It is generally believed that patients with primary generalized epilepsy have normal cognition and neuroimaging studies. We have previously shown that patients with juvenile myoclonic epilepsy (JME) have impaired visual working memory. In this study we examined relative regional changes in 18FDG uptake during a visual working memory paradigm in patients with JME. At rest, there were regional decreases in relative glucose uptake compared to controls. Unlike control subjects, increased activity in the dorsolateral prefrontal cortex was not found during the working memory task. Other regions with increased uptake in controls, such as premotor cortex and basal frontal cortex, also showed no increases, whereas medical temporal structures appeared to play a role in JME but not in control subjects' task performance. The data suggest that JME, a type of primary generalized epilepsy, may suffer from cortical disorganization that affects both the epileptogenic potential and frontal lobe cognitive functioning.

The use of neuroimaging to study behavior in patients with epilepsy

“…To date, a number of studies have demonstrated relationships between regional brain metabolism and both cognitive functioning (47)(48)(49)(50)(51)(52)(53) and mood (54) in patients with epilepsy. In TLE, studies of cognitive functioning have demonstrated associations between left perirhinal and inferior temporal hypometabolism and poor verbal associative memory (55), lateral temporal metabolic asymmetry and impaired verbal IQ and memory (50), left lateral temporal and thalamic metabolic asymmetry and impaired verbal memory and fluency, and left temporal pole hypometabolism and recognition of famous faces (56).…”

“…In a series of functional PET studies, Swartz and co-workers (47)(48)(49) found that impairment in visual working memory was related to less activity in frontal lobe regions in patients with FLE and juvenile myoclonic epilepsy (JME) relative to controls. Instead, FLE and JME patients showed greater recruitment of temporal lobe regions during task performance, suggesting that posterior brain regions were attempting to compensate for prefrontal dysfunction, albeit poorly.…”

Epilepsia Mioclônica Juvenil: endofenótipos distintos considerando aspectos neuropsicológicos, traços de personalidade e variáveis clínicas

“…[2][3][4][5][6] Entretanto, devido ao uso de uma bateria mais ampla, este trabalho pode detalhar quais aspectos das funções executivas e das funções atencionais, frequentemente negligenciadas, encontram-se prejudicados. Desta forma, este estudo demonstrou que pacientes com EMJ apresentam déficits específicos das capacidades de memória operativa, controle inibitório, formação de conceitos, manutenção de metas, flexibilidade mental e fluência verbal.…”

“…1 Entretanto, estudos neuropsicológicos sugerem que indivíduos com EMJ têm desempenho prejudicado em vários testes que avaliam funções cognitivas associadas ao funcionamento dos lobos frontais [2][3][4][5][6] apresentando baixo desempenho especialmente nos testes que requerem formação de conceitos, flexibilidade mental, atenção focal e controle inibitório de respostas.…”

Cognitive Impairment in Epilepsy: A Clinical Study

“…10 Patients with juvenile myoclonic epilepsyshowed deficits in attention, immediate verbal memory, mental flexibility, control of inhibition, working memory, processing speed, verbal delayed memory, visual delayed memory, naming, and verbal fluency.The duration of epilepsy correlated with cognitive decline, and patients with higher education manifested less progression of deficits. 33,34,35,36 Patients with LennoxGastaut syndrome also have rapid and progressive cognitive decline and cognitive outcome is worse for patients with early disease onset. 37,38 Childhood onset absence epilepsy had subtle cognitive deficits and duration of illness, seizure frequency, antiepileptic drug treatment were related to the severity of the cognitive deficits.…”