Developmental task is the most common diagnostic tool used in children with developmental disturbances. It follows according to physiology of the development of the child. Transition through the "mile stones" describes the development of the child in four areas-motor, speech, social and visuo-motor coordination. Systematic diagnostic researches allowed preparation of detailed developmental schemas - motor and psychomotor intelligence. The aim of the work was to present some normal rules of development in motor and speech areas and its biological bases in first years of life. The work presents connections between motor and speech development on a sample of assimilation and accommodation processes described by Piaget.