Synchronization and information processing across the cerebral cortex following cardiac arrest injury

The high frequency of neurological dysfunction after cardiac arrest emphasizes the need for new approaches able to provide an early evaluation of the amount of initial injury as well as the presence of ongoing injury. In the present paper, we apply two synchronization measures to the study of EEG data, namely phase synchronization and mutual information, and evaluate their potential usefulness in the assessment of the degree of brain injury following the cardiac arrest injury. Our preliminary results reveal that phase synchronization in the theta frequency range and the patterns of information flow across the cerebral cortex changes during the one hour after the cardiac arrest event. Therefore, measures of synchronization applied on the brain's electrical signaling can provide a new quantitative assessment of the brain response to injury, as well as the recovery process of neurological function after cardiac arrest.