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Course: Health and medicine > Unit 8
Lesson 12: Miscellaneous topicsALS - Amyotrophic lateral sclerosis
Sal explains the disease ALS, amyotrophic lateral sclerosis, and takes the "ice bucket challenge.". Created by Sal Khan.
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- Who started the ice bucket challenge?(20 votes)
- Pete Frates who suffers from ALS is credited with starting the challenge.(21 votes)
- What is the current life expectancy of an individual who is found to have ALS. In the video, Sal indicates that Stephen Hawking has actually lived for decades after contracting the disease while in the case of Lou Gehrig - the disease claimed his life in two years?(15 votes)
- According to the ALS association, the average life expectancy of someone with ALS is 2-5 years after diagnosis. About 50% die within 3 years, 20% live for more than 5 years, 10% more than 10 years, and 5% more than 20 years. When Stephen Hawking was diagnosed at age 21 he was told he could expect to live another 2 years. That was over 50 years ago.(13 votes)
- If the disease progresses, what will cause the paralysis? The amyothrophication or the inabillity of the neurons to send signals to the muscles?(2 votes)
- When you have ALS, does it paralyse a muscle in a short time period (a day) or do you first lose control of small and precise movements with that muscle? In other words: does it affect individual muscles gradually, or instantly?(2 votes)
- It doesn't paralyze a muscle within a day, the progress (or degeneration rather) is gradual. It will take a few months to around a year for the symptoms to become quite visible. I don't know when the disease gets 'triggered', but I do know that patients can live for many years with the disease BEFORE diagnosis without even knowing that they have ALS. Yes, fine motor activity is the first to get affected. Dropping things frequently, finding simple tasks like buttoning a shirt near impossible, difficulty in maintaining a steady hand while writing with a pen, holding a spoon to eat... they all become very tiresome tasks when the disease has set in (initial stages)
The loss of mobility / movement takes much longer, often taking up to 2-3 years to manifest...before the patient becomes dependent on some kind of 'aid' to assist in movement.
Hope this helps!(1 vote)
- (Why) Does ALS only affect muscle nerves? Do they also affect smooth muscle nerves?(1 vote)
- https://en.m.wikipedia.org/wiki/Amyotrophic_lateral_sclerosis
We do not know the cause of this problem, we only know there is progressive skeletal muscle paralysis due to death of motor neurons. Smooth muscle neurons are not affected. This eventually prevents swallowing and breathing. Many, but not all, patients die within a few years. Stephen Hawkins is someone that has lived a long time with a progressive muscle disease. I guess you might say that the actual lesion can't be examined before death however there is a gene that is a factor in a small number of cases.(3 votes)
- I am doing a science fair project on ALS trying to come up with a solution for better communication. If anyone has a family member or knows someone with ALS alive or dead. What is something you would have liked to help communicate?(2 votes)
- Watch the movie "The Butterfly and The Diving Bell". We used a similar method of communication. Each blink corresponds to a letter, much like a sorting algorithm. That is tedious work and takes up much time and needs a lot of patience. The future of communication in such a scenario would be wireless/ non-invasive BCI with almost real-time interpretation.(1 vote)
- Does this disease effect a certain gender more frequently?(2 votes)
- Males 1.5:1 Females. So yes, it effects males more.(1 vote)
- Does this disease effect a certain race more frequently?(2 votes)
- if motor neuron degenerates than what happens to the relay neuron as relay neuron connects both the motor and sensory neuron,does relay neuron stops working(2 votes)
- No, the sensory neurons are not affected. ALS patients can feel, but their reflexes are affected because of muscular atrophy.
Like you want to take your hand away from the heat source, but your hand is not able to move on time. (delayed or non-existent response)(1 vote)
- Why did he mention the ice bucket challenge in this video?(1 vote)
- The ice bucket challenge is done to show sympathy for people with ALS because that's what the condition feels like.(2 votes)
Video transcript
- ALS or Amyotrophic Lateral
Sclerosis is an extremely debilitating and usually fatal disease and it's a horrible disease. You have your motor neurons,
the neurons that are essentially activating your
muscles, telling your muscles when to twitch or when to
contract and that these neurons, these cells that traverse,
that go from your brain all the way to your muscles, so there's these unusually long cells. They go through your spinal
cord, they degenerate. They degenerate and as they degenerate, there's no way for your
brain to send the signals to your muscles to do the
things that your muscles need to do and so your muscles atrophy and so that's actually
where the first part of ALS comes from, the "A" in ALS, Amyotrophic. "A" means no or not or
kind of the opposite. "Myo" means, is referring to muscle and 'trophic" is nourishment,
so this is one way to think about it is "no muscle nourishment", but what's really happening
is that the muscles start to die away because
they're no longer to be-- They can no longer be activated
because, I guess you could say, the wires or motor
neurons that would normally activate them, they degenerate
and what's especially horrible about this is,
obviously, it causes paralysis, people lose control over
basic things including their speech, is the whole time that
this is happening and this is degenerating, the individual
in question has full mental awareness, so they're fully
aware of what's going on in their body so you could imagine
it's a fairly horrible thing for people to go through and
there have been many famous cases of people with ALS, most
famously probably Lou Gehrig. In fact, ALS in the U.S.,
at least, is often called Lou Gehrig's disease, one
of the most famous baseball players of all time for
the New York Yankees. He died of ALS, really,
when he was about my age in his late 30s. Stephen Hawking, he is one of
the small percentage of ALS sufferers who have been
able to live several decades past his diagnosis. It effects one to two out of
100,000 individuals each year. So if you were to imagine kind
of a large stadium of people, in a given year you would expect to-- If you say there's roughly
100,000 people here, you would expect one to two of them to get afflicted with ALS. The reason why it's important
to have research behind this is it's a very, a very not
so well understood disease. People know what happens. They know that the motor
neurons degenerate, but they don't know why it's happening. There is-- Scientists have identified some
genetic component to ALS for some of the sufferers, but
for the majority, they can't identify a genetic component
and it's unclear what environmental components are causing it, although people think there
must be some environmental components, but as far as
most people can tell it just randomly afflicts people once
they kind of get into their early middle age, so it's a
really, really horrible disease and it's really important that
people have awareness for it and that there is an
appropriate level of funding and in case you're wondering, yes, I did take the ice
bucket challenge as well. I have been challenged by
Shawn O'Sullivan to do the ice bucket challenge,
so I'm about to do it. Y'all ready? - Girl: Yeah
- Boy: Yeah - [Voiceover] : (giggling) - Ah. - [Voiceover] : (laughing) - I'd now like to issue the
challenge to three other people. The other Salman Khan,
famous Bollywood actor. Esther Cho, who works
with me at Khan Academy and my kids, who seemed
too happy to see myself get doused with cold water.