A modified corticothalamic (MCT) system with multiple delays for epileptic absence seizures is taken as a study object. Synchronization transition dynamics of two time-delay interconnected MCT systems via nonlinear control is investigated in this paper. Both the intrinsic delays in a single MCT system and the coupling delays between two MCT systems are considered. When there is no control, it is found that the occurrences of synchronization are dependent on the specific deviations of intrinsic delays and also correlated with the rhythmic periods of oscillations for the two MCT subsystems. To obtain the synchronous state transitions irrespective of the intrinsic delays, based on the Lyapunov stability theory, we propose a nonlinear adaptive control schemes with respect to the coupling delays. The numerical simulation results show the effectiveness of the designed control method.