Nonlinear dynamics of heart rate in epilepsy

The relationships between onset of ictal activity and changes in heart rate are examined using Poincare analysis based on R-to-R intervals from EKGs recorded simultaneously with multi-electrode EEGs. The R-to-R intervals are used to compute 2-D and 3-D Poincare plots, where 2-D plots are scatter diagrams of intervals against adjacent intervals, and 3-D plots include intervals as a function of time. Data was examined beginning several minutes prior to seizure. The Poincare technique was chosen due to its noted success in the study of heart failure and the existing relationship between epileptic seizure and syncopal attacks. The intention of this paper is to identify heart rate as a valid indicator of precursor activity in epileptic seizure occurrences. This is done through visual observation of rotated 3-D Poincare plots and the Student's t-test technique to identify recorded measurements of pre-ictal heart rate activity. Finding a relationship between heart rate variation using R-to-R intervals may be significant in distinguishing heart rate as a precursor agent of neurological seizure occurrences.