A Comparative Study of the Regularization Parameter Estimation Methods for the EEG Inverse Problem

الموضوعات

علوم تطبيقية وتكنولوجية

الملخص

Investigation of the functional neuronal activity in the human brain depends on the localization of Electroencephalographic (EEG) signals to their cortex sources, which requires solving the source localization inverse problem. The problem is ill-conditioned and under-determinate, and so it is ill-posed. To find a treatment of the ill-posed nature of the problem, a regularization scheme must be applied. A crucial issue in the application of any regularization scheme, in any domain, is the optimal selection of the regularization parameter. The selected regularization parameter has to find an optimal tradeoff between the data fitting term and the amount of regularization.Several methods exist for finding an optimal estimate of the regularization parameter of the ill-posed problems in general. In this thesis, we investigated three popular methods and applied them to the source localization problem. These methods are: L-curve, Normalized Cumulative Periodogram (NCP), and the Generalized-Cross Validation (GCV). Then we compared the performance of these methods in terms of accuracy and reliability. We opted the WMNE algorithm to solve the EEG inverse problem with the application of different noise levels and different simulated source generators. The forward solution, which maps the current source generators inside the brain to scalp potential, was computed using an efficient accurate Finite Difference Method (FDM) forward solver. Our results indicate that NCP method gives the best estimation for the regularization parameter in general. However, for some levels of noise, GCV method has similar performance. In contrast, both NCP and GCV methods outperforms the L-curve method and resulted in a better average localization error.Moreover, we compared the performance of two inverse solver algorithms, eLORETA and sLORETA. Our results indicate that eLORETA outperform sLORETA in all localization error measures that we used, which includes, the center of gravity and the spatial spreading.

روابط وملفات

التعريف والنوع

رقم الوثيقة

0faa0280-f865-4cdd-a066-4598ee4f809a

رقم العقد

0

نوع الوسائط

Crawler

نوع المحتوى

الرسائل العلمية

صيغة المصدر

رسائل ماجيستير

نوع الملف

pdf text

أسماء الملفات

51794_1.pdf

بيانات النشر

ترجمة العنوان

دراسة مقارنة لطرق تقدير معامل التسوية فى مسألة تخطيط كهربية الدماغ المعاكسة

ألقاب المؤلفين

[{"name_ar":"عدنان سلمان","title_ar":"اشراف","title_en":"Supervision"},{"name_ar":"محمد جميل أبوريدى ","title_ar":"اعداد","title_en":"Preparation"}]

اللغة

English

المصدر والدورية

اسم المصدر

A Comparative Study of the Regularization Parameter Estimation Methods for the EEG Inverse Problem

المحتوى والصفحات

عدد الصفحات

0

إشراف وإعداد

الإشراف

عدنان سلمان

الإعداد

محمد جميل أبوريدى

الاقتباسات الببليوغرافية