Pediatric Language and Memory Mapping in Refractory Epilepsy Using Magnetoencephalography

Each subject will have one MEG session with the recordings of baseline resting state, language and memory protocols. Subjects will have a break period between the language and memory tasks. MEG recordings will be acquired for approximately 35 minutes. The subject will be allowed to practice the language and memory tasks before the MEG recording to feel familiar with them. This practice phase will be a short version of the task administered by a computer and will take approximately 6 minutes.

"The subject will perform a practice session where they will be instructed to try to remember a set of five audibly spoken English words, deemed targets (jump, little, please, drink, and good). Depending on the subject's overall verbal memory capacity, the target words will be presented once or twice during the practice phase. Subsequently, during the MEG recording, the five target words will repeat in a different random order, mixed with a different set of 40 distractors (non-repeating words) in each of three blocks of stimuli. The subject's task will be to listen to the words and lift their index finger of the dominant hand whenever they hear a repeated target word (one of the five). After the language task, the subject will be given a break."

"The subject will be tasked with indicating whether the encoding stimulus matched the retrieval stimulus using two buttons; one for congruent and the other for incongruent response. Button type will be counterbalanced among subjects. The task will take around 16 minutes. The visual stimuli will be projected through an LCD projector onto a white screen located about 0.5 m in front of the subject and subtending 1.0-4.0 and 0.5 degrees of horizontal and vertical visual angle, respectively. A MEG compatible keyboard will be used to measure the subject's responses for congruent and incongruent. The subject will practice the memory task before going to the MEG system using a computer from MEG laboratory. This practice phase will consist of a short version of the memory task with duration of approximately 4 minutes."