It should be assumed that human linguistic and intellectual capabilities are gradable, which follows from both the laws of evolution of the human species and from developmental stages of each individual. The order of succession of the stages in the process of formation of mental functions is determined by the principle: from the most primitive to the increasingly complex. This hierarchy is based on neurobiological determinants: all the levels of the brain organization participate in the processes of forming and receiving utterances, from the oldest or the brain stem, which is connected with the readiness to speak and automation of vocal sequences, to the limbic level, which regulates the emotional and motor aspect of utterances, to the youngest or cortical level, which is responsible for language planning. The paper presents strategies that should be adopted to stimulate, shape and rebuild linguistic behaviors of children and adults with neurologically-based speech disorders. These strategies stem from the evolutionary and ontogenetic laws of the development and functioning of the human nervous system.