Mental confusion, also called delirium, is a change in a person’s awareness. Confusion affects how a person thinks, sees the world around them, and remembers things.
The main signs of mental confusion or delirium are sudden changes in awareness. A person with confusion or delirium might suddenly get very sleepy and unaware of their surroundings or act very upset.
Hypoactive, or low activity. Acting sleepy or withdrawn and "out of it."
Hyperactive, or high activity. Acting upset, nervous, and agitated.
Mixed. A combination of hypoactive and hyperactive confusion.
The main symptom is a change in general awareness and consciousness. This may include:
A shorter attention span
Trouble remembering things, writing, or finding words
Speech and thoughts that do not make sense
Not knowing where they are, what day it is, or other facts
Mixing up day and night and difficulty sleeping
Personality changes, restlessness, anxiety, depression, or irritability
Seeing things that others do not (hallucinating) or believing things that are not really happening (delusions)