Semantic information has reached an objective condition after a lengthy history of semantic inquiries that instrumental neurophysiological devices--such as event-related potentials, electroencephalographic spectral analysis, regional brain circulation, PET scan, deep brain electrodes, and other--have made easier. In turn, internal language, as screened according to Vigotsky's perspective, is considered a product of semantic information circulation understood as neurosemae interconnection. Finally, in normal adults, thinking processes are assumed to be made up by both sensoperceptive information (proprioceptive information included) and semantic information. Thus, an "extraverbal thinking" can be distinguished, whose activity is hardly describable in healthy adults but should be considered as a condition of non-educated deaf persons, and a "verbal thinking", or internal language, made up by semantic information.