Introduction
Epilepsy is the most common neurological condition in childhood and patients frequently present to neuropsychological clinics due to a number of factors related to their seizures, including difficulties with attention, learning, and behavior. Specific cognitive impairments often accompany epileptic syndromes, and these translate to academic underachievement. Patients also present with psychiatric symptoms including inattention, depression, and anxiety. Treatment, including antiepileptic drugs (AEDs) and surgery, can be related to alterations in cognition. As such, continual monitoring for changes in neurocognitive functioning is recommended.
Classification of seizures
Etiology
A seizure is defined as the discharge of abnormal electrical activity in the brain; a diagnosis of epilepsy is made when an individual has recurrent seizures with electroencephalographic (EEG) confirmation [1, 2]. While EEG affirmatively diagnoses up to 70% of individuals with epilepsy, clinical, subjective, and objective observations typically corroborate EEG findings in order to support a diagnosis.
Three mechanisms that occur at the cellular level have been implicated in the development of epilepsy [1]. Defects involving ion channels may result in the prolonged opening of sodium or calcium channels, excessively depolarizing the presynaptic membrane, and resulting in epileptiform activity [3]. The presence of excessive excitatory (glutamate and aspartate) or deficient inhibitory (GABA and glycine) neurochemicals may also increase brain activity, leading to seizures [2]. Third, cellular changes, such as the development of excitatory pathways or synaptic reorganization, can lead to epilepsy, also known as the “kindling” effect [3].