The notion of mental deficiency encompasses all clinical forms established over the centuries, encompassing various forms and clinical types of varying degrees. The term was introduced as a notion of gender by Anglo-Saxons and Americans in the early twentieth century and in Europe was replaced by many other terms: intellectual disability, intellectual weakness or intellectual disability. Schoolchildren with mental disabilities investigated, rhythm and speech disorders, nausea and voice disorders, as well as alalic disorders are an important chapter of correction activities, carried out in language therapy offices, especially since these disorders are often associated with diseases of the motivational-affective and action-volitional sphere.