Temporal recruitment of cortical network involved in reading epilepsy with paroxysmal alexia: A combined EEG/MEG study

Reading epilepsy is a reflex epileptic syndrome in which all seizures are precipitated by the act of reading. Seizures characteristically consists of reading-induced myoclonic jerks of the jaw or throat which may progress to secondary generalized tonic–clonic seizures if reading is not interrupted. In atypical forms many other types of ictal symptoms have been described: abrupt loss of consciousness, absences, visual symptoms and paroxysmal alexia or dyslexia that suggests a left posterior cortex involvement. Reflex seizures are classified as electroclinical syndromes with no specific age relationship and can occur as occasional and caused events (alcohol withdrawal, fever), as part of an epileptic syndrome, or as reflex syndrome in which seizures are triggered only in response to a specific trigger, such as reading. The incidence and prevalence of reading epilepsy are unknown but it is probably under diagnosed. The anatomical basis of ictogenesis in reading epilepsy remains poorly understood. Combined EEG, MEG and functional magnetic resonance imaging (fMRI) studies have found left-dominant activations of motor and premotor cortical areas, but only one MEG study tackled the neuronal recruitment chronology. We performed a combined EEG/MEG study to highlight the spatiotemporal pattern of cortical network involved in the seizure of a patient affected by reading epilepsy.