It has been experimentally shown that a verbal instruction coming from an adult can rather often inhibit a 6-7-years-old child engaged in a activity related 'to the task he fulfills. Corresponingly efficiency of the child is diminished. This effect is to be explained by the attitude of the child: he understands his role as purely executive, and not as a learning one; the instruction therefore is accepted by him uncritically. The rate of conscious acception of instructions increases with age, however even in 7-years-olds it is observed only in 37 % of subjects.