Hi, everyone. Welcome to this week's class on confusion. The word confusion is a very general term that can be used in many different ways. For example, it can be used to describe how we might feel when we're in a strange city and lost and wondering how to get back to our hotel. Or confusion can happen during a conversation with someone and you're not understanding what the other person is trying to say, so you might feel confused. However, in a seriously ill population, this term is sometimes used to describe a problem with someone's ability to think clearly. As it is such a general term, using confusion to describe serious problems with the brain is not an accurate term and may be misleading as to what is going on. Along with confusion, I've heard the word senility and senile dementia used. Again, neither of these terms offer a clear understanding of what is really going on with the seriously ill person who is not thinking clearly. Senility and senile dementia are broad terms that refer to the state of being senile or if being of old age and physical and our mental decline that's associated with old age. We will talk about this topic in an upcoming video, but instead of senile or senile dementia, I will use the term normal aging. In the healthcare world, we use the word cognitive impairment. The word cognitive refers to mental processes of perception, memory, judgment, and reasoning. Impairment means something's going wrong with a person's ability to think and to remember. Cognitive impairment involves a deteriorating process in the brain. It is one that can occur slowly like in dementia or can occur quickly. When it happens quickly, it's called delirium. In delirium there is a quick change in a person's level of consciousness. For this module, we will not be using the terms confusion, senile or senile dementia but instead we will use the term cognitive impairment and we will talk about two conditions of cognitive impairment, dementia and delirium. We will begin in the next video talking about the slowly progressing dementia, one of the forms of cognitive impairment. Dementia is not a specific disease, rather it's an overall term that describes the slowly progressing disease that affects thinking, remembering and reasoning, that impacts behaviors to such a great extent that it interferes with a person's daily life and activities. These behaviors include memory, language, and locomotion or the ability to walk, visual perception, problem solving, ability to manage self and the capacity to focus and to pay attention. Sometimes people with dementia are unable to control their own emotions and their personalities may even change. Join me in the next video, we will talk about the types of dementia.