Consciousness is defined as the state in which people retain knowledge about themselves and about the environment in which they find themselves. Therefore, when any change occurs in this state, you can produce different disorders, depending on the severity of their application for the cognitive and affective mental functions. Among the most frequent alterations of consciousness we are: lethargy or drowsiness, which is reduced alertness or lack of care and degree of daytime sleepiness; confusion, it would be a little more serious than lethargy, because it causes the person spatiotemporal disorientation and even stages of dreams or hallucinations; stupor, wherein the patient is asleep and reacts only permanently by stimulation, but only with simple answers; and coma, a state in which there is lack of reaction to any stimulus and, depending on the patient, can cause a persistent vegetative state or have a minimally conscious state, with certain facial expressions or vocalizations.
Consciousness are often characterised by any change in the consciousness of an individual, from total self-awareness to a complete lack of it. Minimal conscious states and persistent vegetative states are also categorised as consciousness disorders. Consciousness is defined as the state in which people retain knowledge about themselves and about the environment in which they find themselves. Among the most frequent alterations of consciousness are: lethargy or drowsiness, confusion, and comatose states.