Manifestation of ocular-muscle EMG contamination in human intracranial recordings

Christopher K Kovach, Naotsugu Tsuchiya, Hiroto Kawasaki, Hioyuki Oya, Matthew A Howard, Ralph Adolphs

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81 Citations (Scopus)

Abstract

It is widely assumed that intracranial recordings from the brain are only minimally affected by contamination due to ocular-muscle electromyogram (oEMG). Here we show that this is not always the case. In intracranial recordings from five surgical epilepsy patients we observed that eye movements caused a transient biphasic potential at the onset of a saccade, resembling the saccadic spike potential commonly seen in scalp EEG, accompanied by an increase in broadband power between 20 and 200 Hz. Using concurrently recorded eye movements and high-density intracranial EEG (iEEG) we developed a detailed overview of the spatial distribution and temporal characteristics of the saccade-related oculomotor signal within recordings from ventral, medial and lateral temporal cortex.
Original languageEnglish
Pages (from-to)213 - 233
Number of pages21
JournalNeuroImage
Volume54
Issue number1
DOIs
Publication statusPublished - 2011
Externally publishedYes

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