Abstracts

Rationale: The cortical focus theory is the current concept of absence seizures. A small epileptogenic cortical focus spreads to the thalamus and propagates bilaterally to the cerebral cortex. There is no known computer simulation model for absence seizures using the cortical focus theory. The computer simulation will help us understand cortical-thalamic propagation and bilateral cortical involvement in absence seizures. The objective of the study was to develop a propriety computer simulation program that can calculate the propagation latency from the cortical focus to the thalamus and then to the contralateral cerebral cortex. Methods: Using JAVA software, a virtual neuron network was developed for pyramidal layer 2 and 5, and thalamic nuclei. The parameter that was studied in this model was the propagation time (latency)from the cortical focus to the thalamus and contralateral frontal cortex. The cortical neuronal connnectivity was 1:10. The axonal velocities were 10, 20, and 30 meters per second. The association probability was 14% to 10%Results: The cortico-thalamo-cortical propagation latency (10 meters per second axonal velocity) was 39.2, 44.20, 52.50, 54.00, and 50.50 milliseconds when the association probability was 14%, 13%, 12%, 11% and 10%, respectively. The cortico-thalamic-cortical propagation latency was 39.20, 29.70, and 27.60 milliseconds when the axonal velocities were 10, 20, and 30 meters per second, respectively (association probability at 14%).Conclusions: The computer simulation showed that the propagation latencies can be computed using our virtual neuron program. Our preliminary results indicate a negative correlation between axonal velocities and inter-cortical latency. The association probability of 14% showed the shorter propagation latencies.