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Intro to neurodevelopment milestones

Visit us (http://www.khanacademy.org/science/healthcare-and-medicine) for health and medicine content or (http://www.khanacademy.org/test-prep/mcat) for MCAT related content. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video. Created by Emma Giles.

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  • starky ultimate style avatar for user Adewale Grillo
    Hi Guys, I would like to know. Generally are boys later in developing - walking , talking than girls? In the video, time ranges are mentioned and I just observed that my girls were all on the early side of development. I have heard from my colleagues about their boys being on the later side of the range so just wondering.
    (3 votes)
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  • duskpin seed style avatar for user Romana Cvjetković
    How come you say that we start suspecting someone's suffering from cerebral palsy when diagnostics can be done as early ae 4 months? Isn't that what we're trying to acomplish?
    (1 vote)
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Video transcript

- [Voiceover] In this video we're going to talk about neurodevelopmental disorders. Maybe you've heard of some of these disorders before, like Down syndrome, or Attention Deficit Hyperactivity Disorder, also known as ADHD. So these are some examples of neurodevelopmental disorders, but before we talk more about these and some of the other neurodevelopmental disorders. Let's actually start off by breaking this term down, so that we can figure out what exactly a neurodevelopmental disorder even is. So we say neuro here and neuro refers to the brain, right? Well we say that because with each of these different disorders, we see impairments in some of our brain related functions. Things like our memory, our learning abilities, our social skills, our ability to make movements, and maintain our self control. These are some of our brain related functions. And we say developmental here, because these disorders arise when something goes wrong in the brain while it's developing, and this usually happens pretty early on. Often during pregnancy or sometimes shortly after birth. So what I really want to focus on here is classifying these different neurodevelopmental disorders, and the way that I want to do this, the way I want to organize these disorders, is by looking at which brain related functions are impaired, at least primarily in each group. So it turns out that for quite a few of the different types of neurodevelopmental disorders, we can actually start to see some clues that something just isn't quite normal in the brain, and we can see these clues often pretty early on. Sometimes within the first few months or maybe the first few years of life or so, and we sort of get clued in to any potential developmental issues by comparing the developmental milestones of any given child that we may be concerned about, to normal developmental milestones. So developmental milestones, what are some examples of that? Well, things like a baby sitting up without needing to be held or supported, or crawling, or babbling, or even fully talking, or smiling, or making eye contact, all of these little behaviors they should be happening pretty early on, and we kind of know about when they're supposed to happen. So these are some of the milestones that we can use to track that the brain is developing normally. But let's actually look at this a bit better. Let's use a little graph here to talk more about this, because I think it'll help things to sort of make more sense with neurodevelopmental disorders. So let's draw a little graph out here, and we'll put age down at the bottom here on our X axis, and we'll use our Y axis here to categorize those behaviors that we talked about, those brain functions. So let's call one category Social, and then we'll make another one here called Motor, and let's put Cognitive down here. And this will all make sense in a minute, so just go with me for a second. Oh, and I should mention that we normally think about these milestones as age ranges rather than specific ages, because everyone's different, right? Everyone develops at a slightly different pace. So the normal time for a certain milestone is a range to account for these differences that are totally normal between different people. So, for example, let's put something down here that fits into our Social category here. So, somewhere between about the age of one and a half months on our chart here, and about three months. Somewhere between here is when we would expect our baby here to start smiling in response to something. Maybe if mom smiles that makes the baby smile, and we put smiling in our Social category here, because smiling is actually an early indication that the baby is developing its social skills. She's learning to respond to other people, and show them how she feels, and what about our Motor category here? Well let's actually split this up into two. So we've got Fine Motor, so this is things like picking up small objects with your pointer finger and your thumb. And we've got Gross Motor, so big movements that use big muscle groups like our legs. So things like walking without any help at all. So let's actually look at walking as our example for Motor. So the age range that we would normally expect for this motor milestone of walking is somewhere in between about 12 months old here to about 16 months, that would be about the normal range. So walking, I mean if you think about it, it kind of requires pretty good development of a few different motor skills, right? You need to be able to move and coordinate your arms and your legs, and you need to be able to sort of speed up and slow down as necessary, kind of in response to your environment or what you want to do. So being able to walk independently, by yourself, somewhere in this time range here, that tells us that motor development is coming along pretty well. And for our Cognitive category here, well we have the first word, that's a pretty exciting one. So a word like mamma or dadda. We would expect that to come out somewhere in between about nine months here and 15 months. So these are just a few examples of some of the milestones that we know about. So that's kind of a snapshot of what normal development is like, but what happens when someone has a neurodevelopmental disorder? Well, because neurodevelopmental disorders impair some aspect of development, for some kids with some of these disorders, we might actually see a delay in them reaching some of these important milestones, right? And which ones are delayed? Well that really depends on which disorder we're talking about. So I'll give an example in a second here, but let me just say that each neurodevelopmental disorder, generally affects one of these domains here the most. But they're still often detrimental effects in some of the other domains. Although that might not always be the case, it really can depend a little bit on each individual even with the same disorder. So let's use the neurodevelopmental disorder, cerebral palsy, as our example here. So cerebral palsy involves trouble with making movements, and controlling our muscles, because motor development has been impaired in some way. So for a child with cerebral palsy, we often start to pick up on the disorder when they aren't reaching their motor milestones, right? So if our kid here wasn't walking by themselves by about the age of 18 months old, we might start to be a little concerned about how their motor development is going, and in turn we might start to consider developmental disorders of movement like cerebral palsy as the underlying cause. And I won't talk about the cause of these disorders that I'm going to talk about in this video. That gets a little complicated for now, but I just want to focus on laying out the groundwork for thinking about neurodevelopmental disorders. So just sticking with our motor milestones for a second, another disorder where we'd see some motor issues is Tourette's syndrome. So for someone with Tourette's the main signs we see are these unusual, repetitive movements or sounds, like blinking or grunting, maybe. Now for a child with Tourette's we might not really see delays in these milestones. Instead we might notice unexpected movements, or maybe extra sounds start to crop up somewhere between the ages of about three and nine years old, but we still say that something like Tourette's is a neurodevelopmental disorder, because the reason the person has it is because there was some sort of event that occured during development, right? And that affected a part of their brain. So what about our social domain here? Well an example of a neurodevelopmental disorder in this domain, would be autism spectrum disorder. Where the main thing that we see are impairments in social skills. Well for someone with autism spectrum disorder, we might see clues of these social impairments if our baby here isn't smiling by about the age of three months old. That's starting to get a little late to develop that behavior, and actually, probably one of the most specific signs of autism spectrum disorder, would be if our child here just wasn't really making meaningful eye contact with mom or dad. Then we might start to think about a developmental disorder of social skills like autism spectrum disorder, and another disorder that we can put down as a social or behavioral disorder here, we can put down ADHD. And someone with ADHD, what they have trouble with is really focusing on particular tasks for too long, and sometimes they struggle with being hyperactive or restless. So with ADHD, even though we put it down here because it's more of a behavioral disorder. Kids with ADHD often also have language impairments. So if our child here wasn't saying their first word around, about this age range. Well we might start to consider ADHD as a possible underlying neurodevelopmental disorder. And finally our cognitive milestone section here. Here's where we put disorders like Down syndrome, which manifests as various intellectual disabilities. Like problems with learning and memory, or even language. So we might start to consider an intellectual disability like Down syndrome if our kid here isn't meeting some of these cognitive milestones. So if they aren't saying their first word by about this age range, we may also start to consider things like Down syndrome. And let's put down Fetal Alcohol Spectrum Disorders, or FASD over here with Down syndrome. So FASD is another disorder where we see people having trouble with quite a few different intellectual tasks, like learning or speaking. So for these disorders here that we've looked at, these are just examples of some of the milestones that might be delayed in someone with one of these disorders. Sometimes we might not really see any major delays in our key milestones, and sometimes we might see quite a few delays in several different milestones, and this can depend on things like the specific disorder that the person has, and the severity of the impairments or damage in their brain. But hopefully this gets you thinking a bit about milestones and normal development, and the different types of neurodevelopmental disorders.