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Health and medicine
Course: Health and medicine > Unit 9
Lesson 10: Dementia, delirium, and Alzheimer's- Dementia and Delirium, including Alzheimer’s
- What are dementia and Alzheimer's
- Alzheimer's disease: Plaques and tangles
- Other types of dementia
- Risk factors for dementia
- Stages of dementia and Alzheimer's disease
- Diagnosis of dementia and Alzheimer's disease
- Treatment of dementia and Alzheimer's disease
- What is delirium?
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What are dementia and Alzheimer's
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Want to join the conversation?
- Can someone be diagnosed with Alzheimer's, or do you have to guess, like schizophrenia? Also, are the symptoms universal, or do they vary from patient to patient?(5 votes)
- People can be definitively diagnosed with Alzheimer's. The symptoms may vary, but will be within a defined set and can lead to a diagnosis.(5 votes)
- Can anyone of any age have dementia I too forget things like when I had to go get something to write with but then once I got to my room I couldn't remember what I was looking for...(2 votes)
- Sometimes when you enter a room or go down a hallway for example, its common for most people to forget what they were supposed to be doing there in the first place. Its called the boundary effect, or the doorway effect. It isn't really understood all that well why this happens, but it could have something to do with the change of environment. Or, if you're like me, you are usually thinking about something totally different than what you were going in that room to do on your way there, and then you forgot your original purpose of being in that particular room at all.(4 votes)
- Can dementia happen in younger people? Do all people have the same symptoms or are they different per person?(3 votes)
- anybody can get it, even kids, but it typically comes over age 65(1 vote)
- Would chronic traumatic encephalopathy be considered a form of dementia?(1 vote)
- Yes. It is currently a poplar topic when referring to professional sports, especially football and soccer. CTE causes the same type of changes seen in dementia, except that they tend to occur earlier in life. It is a serious concern facing professional contact sports; one that has been actively kept out of the mainstream media, at least here in the US. Because it isn't a popular topic of discussion, less research has been done on this specific cause of dementia.(4 votes)
- Are infectious agents the other cause of dementia apart from Alzheimer?(1 vote)
- They are not "the other cause" apart from Alzheimer, but certain infectious agents can cause dementia, so they are "another cause". The HIV ( AIDS) and prions ( BSE, "Mad cow disease") are both known to increase the chances of dementia, and there are other diseases too that can cause dementia. These types of dementias aren't classed as Alzheimer's disease, and they are not a type of delirium.(3 votes)
- Is AD a type of disease caused by prion? aggregate of proteins form, brain cleans these aggregates, empty wholes left after cleaning, brain shrinks overtime
AD=> Amyloid plaques =>brain shrinks...(1 vote) - Do you have any ideas on keeping an elderly person's mind active to prevent the worsening of dementia?(1 vote)
- I know scientists have discovered an ingredient found in Jellyfish, and you can also take a medicine that slows down the process, but other then that i am not so sure....(1 vote)
- Full meaning of SSRIs and its relation mental disorders especially dementia and delirium(1 vote)
- Is there any reason to expect Alzheimer's Disease to be more likely if you already have executive function issues? For instance, some learning and cognitive disabilities like ADHD and autism already impair memory and planning skills. Is there any reason to think that Alzheimer's would be more likely or more severe if the person already has one of those impairments? Or would it just make it more difficult to diagnose? Or none of the above?(1 vote)
- I think it is just more likely if Alzheimers comes in the family....(1 vote)
Video transcript
- [Voiceover] Let's say you're
going to the grocery store, but you realize you left
your keys in your room. You go up to get them and
then walk into the room and look around for a second,
and realize you completely forgot why you even came
here in the first place. We all know how frustrating
this can be, right? But this scenario is totally
normal and is something everybody experiences from time to time. And besides causing you
to take one more trip up the stairs to your room
after you remember again, it doesn't throw off your day too much. When problems remembering or problems with your thinking skills
in general become so severe and so common that they actually interfere with your daily life, it might
be diagnosed as dementia. Dementia, though, is
not a specific disease. What do I mean by that? Well, it's more of a
general term that describes a range of potential
difficulties with reasoning, judgement, and memory. For example somebody with
dementia might have troubles with speaking or writing
coherently, or understanding what was spoken or written. They also might have trouble
recognizing their surroundings, especially when those
surroundings should normally be very familiar to them. Planning and performing tasks
that require multiple steps can also be difficult for
patients with dementia. Even tasks that you might
think are really simple, like getting dressed and
eating, these can become a serious challenge for patients
with later-stage dementia. And to make matters worse,
many times, patients aren't even aware that they're
experiencing any troubles or any sort of cognitive
deficiencies at all. Now, dementia is most
common in the elderly, especially after age 65. But it is certainly not
a normal part of aging. So, dementia, in very general
terms, is something we use to describe when someone
has troubles learning, remembering, and communicating. But where does Alzheimer's
Disease fit into this? Well, Alzheimer's Disease
is a type of dementia. Specifically, it's what's known as a neuro degenerative
disease, and it counts for about 60 to 80% of all cases of
dementia, affecting about five million people. So, if we look at "neuro,"
we know that this refers to the nerves of the nervous system, or basically your brain,
and then, "degenerative" or "degeneration" means to
decline or to deteriorate. So, with Alzheimer's Disease,
there's this deterioration of your nerve cells in your brain. And this brain of yours
houses about a hundred billion nerve cells, which are
also called neurons. And these guys communicate using a hundred trillion connections. That's a lot. Now, this communication
and those connections are what control essentially
every other organ and every other function in your body, not to mention your thinking abilities. Unfortunately, though,
the main type of cells that Alzheimer's Disease
targets and affects are these precious neurons. And depending on where
the affected neurons live in your brain, different
functions of your brain can be affected. For example, if nerve cells
in this area of your cerebrum are affected, you might have
trouble solving problems or making plans, because
these cells help you do those things. Or, if the neurons in
this area are affected, you might have problems
remembering something or storing new memories. And as Alzheimer's Disease progresses, more and more of these
neurons die, and your brain tissue actually begins to
shrink due to this loss of nerve cells. All right. So, nerve cells in your
brain are destroyed in Alzheimer's Disease,
but how are they destroyed? Well, unfortunately, answers
to seemingly fundamental questions like these aren't
really fully understood yet. But scientists have pinpointed
a couple of possible culprits that usually seem to be involved, and these are called plaques and tangles. Plaques are like these
weird, abnormal clusters of protein fragments that build up between neighboring neurons. So, this is a normal group
of nerve cells going about their business, you know,
communicating and what-not. With Alzheimer's Disease,
these plaques start to form in between these neurons,
which is thought to make it a lot harder for them to communicate. Now, besides plaques, the other hallmark of Alzheimer's Disease are called tangles. Unlike plaques, though,
these guys are found inside the neurons, and most of
these are made up of a protein called tau. And tau proteins are helpful usually, but in Alzheimer's Disease,
they're all twisted and abnormal, which ultimately
ends up hurting the cells. Okay. But we still haven't
said why these plaques and tangles form. Well, again, that question
is still a huge, huge area of research, and is something
scientists continue to gain insight on but have yet
to completely understand.