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What is autism spectrum disorder?

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Video transcript

- [Voiceover] So autism spectrum disorder is a really broad social disorder that affects the way that someone communicates and interacts with other people. And the reason that I say it's a really broad disorder, the reason we call it a "spectrum disorder" is because each person with autism spectrum disorder is affected a little differently. No two people with autism spectrum disorder are exactly the same. So we say that different people with autism spectrum disorder fall along a spectrum, and along this spectrum there are different symptoms, different challenges and different abilities that vary a lot in severity and vary a lot between different people with autism spectrum disorder. So while this is a spectrum disorder and everyone with autism spectrum disorder has different experiences, there are a few key signs that are common among people with autism spectrum disorder, and we're gonna check these out so that we can understand a little bit more about what autism spectrum disorder is. So there are a few different ways that we could characterize these common signs of autism spectrum disorder. I'm just gonna do it in this way, but there are some other possible ways out there too. So first, let's pop down communication and social signs. This will be our first category here. And next, we'll write down behavioral signs. And then our last category, let's put responses to environmental stimuli. Sort of just the way someone responds to things that they see or they encounter, and this will make more sense as we get to it. All right, so let's start off by looking at this first category here, communication and social signs. So, I'm gonna draw a face here, and I'm gonna draw this expression here that's supposed to look like boredom. Now, I'm no artist, so you might need to kinda use your imagination here to see the boredom, but that's what it's supposed to be. So, for someone with autism spectrum disorder, they might not really notice or pickup on this facial expression here and realize that this person is trying to indicate that they're bored. They might have trouble noticing these sorts of nonverbal cues that are often used when people chat, so someone with autism spectrum disorder might continue a conversation with this person here and not really pick up on this boredom, because aren't really aware of this nonverbal cue, this facial expression that's supposed to show boredom. So let's look at another nonverbal cue just so we get a better idea. So maybe instead of being bored, this person might be, I don't know, getting a little defensive for some reason, so let's cross their arms here like this, the way we sometimes do when we're feeling defensive and this might be this person's way of showing that they're getting defensive about something in the conversation. And again, for someone with autism spectrum disorder, they might not really see this arm crossing as a sign of defensiveness. This nonverbal cue doesn't really indicate to them that this person here is feeling defensive, so they might continue on with the conversation as though nothing is happening, because this arm crossing's not really telling him anything. So maybe we can kinda summarize this as trouble understanding the emotions and behaviors of others. So this is one of the types of communication and social signs that we see in someone with autism spectrum disorder. And again, keep in mind that autism spectrum disorder is just that, it's a spectrum, so people might have different degrees of trouble understanding the behaviors of others, maybe a little, maybe a lot, it varies a lot between different people with the disorder, but you can imagine here that if someone with autism spectrum disorder doesn't quite see and read the emotions and behaviors of others, if they don't quite understand communication in the same way as people without autism spectrum disorder do, well, this can make it a little tricky for them to communicate with others, right? So for children with autism spectrum disorder, they might not quite know how to express themselves and communicate what they need or what they want, so they might grab or scream because they don't really have any other way to get what they need or what they want, and for kids that are a bit older and have autism spectrum disorder, well, not really being able to see or read the emotions of others and not really being able to communicate in these sorts of ways themselves, this can make it a little tricky for them to connect with other people. So sometimes for people with autism spectrum disorder, they might struggle to fit into a group of people or maybe they just prefer to hang out on their own. All right, so if move to our next category here, we've got behavioral signs of autism spectrum disorder. So to check out some of these, let's actually make a graph here showing different levels of interest in activities, and stay with me here, it'll make more sense as we go along. So let's make our y-axis of our graph here "level of interest" and we'll use this pink color here to draw what we might expect for a kid and we'll use this green color here to draw what we might see for a kid with autism spectrum disorder, and let's put a few different activities down here. So we'll do that on our x-axis. So maybe we'll pop down activities or interests like sports, maybe we'll pop down soccer and horseback riding, and let's put down interest in cars and playing with blocks. So these are some of our activites and we'll look at the different levels of interest that we might expect kids to have in these activities. So maybe for horseback riding here, we could kinda say that we would expect a kid to be about this interested in horseback riding. It's kinda arbitrary, but you know, some kids like horseback riding, some kids don't, so let's put that about here. Now, for me, I loved horseback riding. I loved it way more than the average kid, so I'm just gonna put down where I would be, which would be way up here, way more interested than probably what you would expect for the average kid. And if we look at soccer, you know, lots of kids like soccer, but lots of kids don't like soccer, but you might be more likely to play soccer, maybe you play at a gym or after school with your friends and that's maybe not so much the case with horseback riding, so maybe more kids like soccer than they do horseback riding. So maybe we'll say that the level of interest that we might expect for soccer would be a little bit higher, so let's put it up here. And cars, I mean, some kids are interested in cars, but some aren't. Maybe we'll put that a little bit lower than both soccer and horseback riding. And then playing with blocks, you know, a lot of kids dig playing with blocks. I'd say that's probably a pretty common interest of a lot of kids, at least at a younger age, so maybe we'll make that the highest one here. So these are just some hypothetical levels of interest that we would maybe expect from kids. So for kids with autism spectrum disorder, one of these signs, these behavioral signs that we see, is what we call "restrictive behavior," and what we mean by that is that their interest can be really restricted or limited compared to what we might expect from a child just in general, a kid without autism spectrum disorder, and when they do have an interest in something, they can often be quite a bit more interested than what we might expect in general. So maybe for someone with autism spectrum disorder, they really don't show any interest at all in any sports, not soccer, not horseback riding, no sports, and they aren't really keen on playing with blocks either, but they're really, really, really into cars. They love anything to do with cars, so their interest level is way up here. Maybe if they were able to, they would spend all day thinking and playing and talking about cars. So we might say that their interests are kind of restricted to cars, and there's pretty much no interest in any of these other hobbies, not even a little bit, like we might expect. Now, trying to decide whether kid's interests are really restrictive, that can be a little subjective, a little hard to figure out. I remember when I was a kid, I really didn't care about anything other than horseback riding. My level of interest for horses was way up here, way more than what you would expect for a kid, so it is kinda hard to draw the line on when the kid is being obsessive or restrictive with their interests, but in general, people with autism spectrum disorder have this sort of restrictiveness with their interests. They might have an activity or two that they're extremely interested in and then show almost no interest in any other activities. Now while we're under this behavior category, we can also put down "repetitive behavior" as another kind of sign that people with autism spectrum disorder can have, and when we say "repetitive," what we mean are things like needing a lot of routine. So maybe a child with autism spectrum disorder really needs to have the exact same meals everyday, or the same bedtime rituals, or maybe they have a habit of repeating certain behaviors like lining up toys or repeating certain words. These kinds of repetitive behaviors are another sign that we can see in kids with autism spectrum disorder. So let's head over to our last category here, responses to environmental stimuli. Now, what do I mean by that? Well, let's make another graph here. We love graphs, so let's make our x-axis here the stimulus strength, and you'll see what I mean in a second, and we'll make our y-axis the responses that the child has to the stimulus. So maybe we'll make a low strength stimulus, something like a dim light. It doesn't really excite too many people, a lot of might people might not even notice it, and then something a little bit stronger would be a noise, maybe like a car honking, and then we'll put down a high strength stimulus as something like being squeezed really tightly by another person. So we would probably expect a kid to respond the least to this dim light, our low strength stimulus, and then respond a little bit more to this medium strength stimulus, the car honking, and then respond the most to this high strength stimulus of being squeezed really tight. So we can kind of make this line here. So we would expect that the higher the stimulus strength, the greater the response, right? But it turns out that for a lot of kids with autism spectrum disorder, they don't necessarily really follow this line. Some weak stimuli really, really bother them, so maybe their response would be kinda up here, but then for some strong stimuli, they don't really bother them at all, so maybe their response would be kinda down here. So it really does vary which stimuli evoke which responses, but in general, what we see with a lot of kids with autism spectrum disorder is that they don't really follow this expected line here. So everything we've looked at here, these aren't the only signs that someone might be on the autism spectrum, but hopefully now you can see that autism spectrum disorder is primarily a social interaction and communication disorder.