The dynamics of cognitive functions of students of faculties of natural sciences has been analyzed during verbal task solving. EEG and time required for solving of model learning tasks have been registered. Solving of learning tasks was divided into three stages. The first stage was connected with the task reading and preparation for the answer, and was followed by activation of the long-term memory. At the second and third stages, which were connected with formulation of the answer and text writing, the key role belonged to the working memory.