Abstract
Epilepsy is a brain disorder characterised by the recurrent and unpredictable interruptions of normal brain function, called epileptic seizures. The present study attempts to derive new diagnostic indices which may delineate between ictal and interictal states of epilepsy. To achieve this, the nonlinear modeling approach of global principal dynamic modes (PDMs) is adopted to examine the functional connectivity of the temporal and frontal lobes with the occipital brain segment using an ensemble of paediatric EEGs having the presence of epileptic seizure. The distinct spectral characteristics of global PDMs are found to be in line with the neural rhythms of brain dynamics. Moreover, we find that the linear trends of associated nonlinear functions (ANFs) associated with the 2nd and 4th global PDMs (representing delta, theta and alpha bands) of Fp1–F3 may differentiate between ictal and interictal states of epilepsy. These findings suggest that global PDMs and their associated ANFs may offer potential utility as diagnostic neural measures for ictal and interictal states of epilepsy.
Highlights
Epilepsy is the second most common neurological disorder after stroke and affects over 50 million people worldwide [1, 2]
We found that six Laguerre functions with Laguerre parameter 0.7, and five global principal dynamic modes (PDMs) with cubic associated nonlinear functions (ANFs) are optimal for both inputs on the basis of Bayesian information criteria [36] for all subjects of the training data set under both ictal and interictal states
The estimated five global PDMs from the training data set for both T7–P7 and Fp1–F3 inputs are shown in Fig 2 in the time- and frequency-domain
Summary
Epilepsy is the second most common neurological disorder after stroke and affects over 50 million people worldwide [1, 2]. According to the International League Against Epilepsy (ILAE) and the International Bureau for Epilepsy (IBE), epilepsy is “a disorder of the brain characterized by an enduring predisposition to generate at least one epileptic seizure and by the neurobiologic, cognitive, psychological, and social consequences of this condition” [3]. Most of the previous work [14, 15] undertaken hitherto emphasized only on the individual EEG channels and did not examine the connectivity across different brain regions while exploring complex brain dynamics. Recent studies [16,17,18] sought an evidence of pathological network disorder following the seizure onset, suggesting to quantify the spatio-temporal functional connectivity of different brain segments to reveal its dynamic behaviour
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
