Distúrbios da Consciência Humana - Parte 1 de 3

The conscience is the perfect state of knowledge of self and the envi ronment, as well as the specific responsiveness to various internal and external stimuli. This article aims to present the morphofunctional and pathophysiological aspects and the neurobiological bases for the most prevalent morbid conditions involving changes in the level of consciousness. For this purpose, we reviewed the literature, supported by articles obtained from LILACS (Latin American and Caribbean Health Sciences), Scielo (Scientific Electronic Library Online) and PubMed (U.S. National Library of Medicine) databases, in addition to textbooks on neurology and neuroscience. In this first article fo cuses on (1) reticular formation – an important neural nerve structure related to consciousness –, which consists of a set of nerve fibers originating after the brain stem, which form ascendant bundles able to reach the diencephalon and activate the telencephalon. Disturbances in these areas, whether traumatic or not, can lead to impairment of the thalamocortical functions, and hence to changes in the level of consciousness.