Model of Visually Evoked Cortical Potentials

J. KREMLÁČEK, M. KUBA, J. HOLČÍK¹

Department of Pathological Physiology, Medical Faculty of Charles University in Hradec Králové, ¹Department of Biomedical Engineering, Faculty of Electrical Engineering and Computer Science, Brno University of Technology, Czech Republic

Received January 18, 2001
Accepted June 6, 2001

Summary
The pattern-reversal (P-VEPs) and the motion-onset (M-VEPs) of visual evoked potentials were modeled by means of three damped oscillators (O1, O2, O3) of identical construction. The O1, assumed to simulate the response of primary visual area (V1), was driven by the firing density of the lateral geniculate nuclei. O1 contributed mainly to the N75 and P100 peaks of the P-VEPs. The O2, driven by the O1 output, mimics the activity of V2, V3a, and MT. It contributed to the negative peak N145 of the P-VEPs or to the N160 in the M-VEPs. The O3 was suggested to model late slow processes probably of an attentive origin. The model parameters were set by optimization to follow the P-VEPs and M-VEPs obtained as a grand average of four young volunteers (PZ - A2 lead). The evoked potentials were described with normalized root mean square error lower than 13 %.

Key words
Mathematical model · Visual evoked potentials · Pattern-reversal · Motion-onset

Reprint requests
Dr. J. Kremláček, Medical Faculty, Charles University, Šimkova 870, 500 01 Hradec Králové, Czech Republic, e-mail: jan.kremlacek@lfhk.cuni.cz