Attention deficit hyperactivity disorder (ADHD/ADD) – causes, symptoms & pathology

What most people know—or think they know—about
attention deficit disorder, or ADD, is that it’s used to describe somebody who can’t
stay focused…and when they REALLY can’t focus, they have attention deficit hyperactivity
disorder, or ADHD. This continuum from one to the next isn’t quite how it works, though. ADD and ADHD are actually synonymous, as in,
they’re the same. ADD’s an outdated term used prior to 1987, after which it evolved
into ADHD to encompass more of the symptoms that people with ADHD often experience, which
in addition to being inattentive, includes both hyperactivity and impulsiveness. So somebody
might be diagnosed with ADHD because they have symptoms related to not being able to
pay attention, but they also might be diagnosed with ADHD if they have symptoms relating to
being overly active and impulsive. They might also have ADHD if they have symptoms of both. According to the diagnostic and statistical
manual for mental disorders, the fifth edition, the most recent update being in 2013, ADHD
is split into these three subtypes: inattentive, hyperactive-impulsive, or both. Inattentive
and hyperactive-impulse have a set of nine symptoms. For example, someone with the inattentive
subtype might make careless mistakes, or not listen, or be easily distracted; and someone
with the hyperactivity and impulsive subtype might fidget, or squirm around, or get up
from their chair often. Now, you might be thinking that everyone fidgets now and then,
right? Well a diagnosis is given when someone has 6 of the 9 symptoms for either subtype
for at least 6 months. Most commonly though, children have symptoms of both subtypes and
therefore have the combined subtype. Since ADHD is considered a neurodevelopmental disorder,
the symptoms also have to have started between age 6 and 12, and the behavior can’t be
appropriate for their age. Alright, but what causes someone to be hyperactive,
or impulsive, or inattentive? Well, as you might guess, it’s pretty complicated…and
we don’t really know, probably a lot of different factors, and ultimately they all
fall into some combination of environmental and genetic factors. One interesting clue
to a genetic component of ADHD is looking at families—for example, a child with a
sibling that’s been diagnosed with ADHD is more likely to develop it themselves. Furthermore,
if those siblings are identical twins, meaning they have the same DNA, their chances of developing
ADHD is considerably higher. Having identical DNA doesn’t mean that the twin is definitely
going to develop ADHD, though, which again, suggests that both genetic factors and environmental
factors play a part. As to a specific gene, it’s probably not one single gene that leads
to ADHD, but rather multiple genes that determines how severe their symptoms are. These genes
likely influence the production or regulation of the brain’s neurotransmitters, which
are signaling molecules in the brain that are released by one neuron, and received by
receptors of another neuron. This movement from a neurotransmitter from neuron A to neuron
B is basically a message being relayed—it’s like the neurons are talking. Dopamine’s
a specific neurotransmitter that gets released when the brain’s involved with behaviors
like getting a reward, taking a risk, and being impulsive. Norepinephrine is another
neurotransmitter involved in attention and arousal. It’s thought that lower amounts
of these two neurotransmitters floating around contributes to symptoms of ADHD. The reason
why these neurotransmitters might be down in the first place is still not well understood,
and research remains ongoing. Treatment for ADHD can be tricky, since symptoms
may vary from patient to patient, although it most often involves either behavioral psychotherapy,
medication, or both. Behavioral psychotherapy is often targeted at children, and focuses
on teaching the child better time management and organizational skills. For example, having
structured routines that they can follow and then giving rewards when they stick to the
routines. Also, involving both parents and teachers are important, and both behavioral
parent training and behavioral classroom management have been been shown to be helpful for children
with ADHD. For adults, behavioral psychotherapy might focus on ways of decreasing distractions
and also improving organizational skills. If medications are prescribed, typically the
first-line options are stimulants. Since it’s thought that low levels of neurotransmitters
are involved in ADHD, stimulants are used because they tend to increase the number of
neurotransmitters, like dopamine, between neurons, therefore reducing symptoms. Common
and well-known ADHD medications are molecules that are chemically similar to illicit stimulants
like methamphetamine, but there are some key differences to keep in mind here. All of these
chemicals help to increase the release of dopamine from neuron A, but the ADHD medications
typically cause a slow release of dopamine, whereas illicit stimulants like methamphetamine
cause a really fast release of dopamine. In fact, it’s this incredible surge of dopamine
that disrupts normal communication between neurons and produces euphoria, and is the
reason that illicit substances like methamphetamine are highly addictive. In contrast, the slow
and controlled release of dopamine caused by ADHD medications is key, and helps a lot
of patients improve their focus and attention.

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  1. Good explanation for the general public and I'm NOT criticizing this video. But as someone diagnosed with ADHD as an adult (with all the symptoms as a child too), ADHD is much more complicated than described. One example is no mention of hyper-focus that one can have. I'd also love to know more about other ADHD medications such as modafinil (sometimes used off-label for ADHD).

    Any chance of a more detailed explanation in the future? If not, this is still very good to help most people (especially those who don't have it) understand it better!

  2. So I was diagnosed with ADHD when I was in about second grade, and I took medicine for it until the fourth. While it did vastly improve my focus, but also dramatically changed my personality. Most people say that it changed because I grew up, as most people change their personalities from the age right to thirteen, but my parents noticed this. Before I started, I was very excitable and jumpy and very out of focus and had a lot of other child like personality traits, but as soon as I started, i got extremely mellow and I wasn't very active or even that generally happy and excitable. Now, about four years later, I have started to gain back a bit more of my old self, but I am still mostly very mellow and calm, yet I still show many signs of ADD I was trying to lose. Basically, I think the medication works, but not unless you're on it a lot, and it may wear off.

  3. Attention deficts are often times the problem of something larger like another disorder, ADD being a sort of side effect.

  4. I apologize, I just cannot hold it in any longer. I have OCD. ADHD and ADD are NOT the same thing. ADD is when someone doesn't have hyperactivity and ADHD is when they do. I know this because I have been diagnosed with ADHD and my mom has been diagnosed with ADD. I don't know what source you got your information from, but it is incorrect information. Good day!

  5. The thing is with ADHD, I think the subject is widely misunderstood, I think it's wrong to call this 'disorder' ADHD as to me, these are some of the things I suffer under from this 'disorder'

    People that does not have ADHD CANNOT understand what happens in my head on a daily basis, you guys HAVE NO CLUE what I am going through everyday, and what is particularly interesting, to me, is that the medication DOES NOT work as intended on me, I've been through SO MUCH medication in my childhood, all of which did not seem to have the intended outcome, it made some of my symptoms a LOT worse.

    Let me give you an example.

    We all, obviously, understand the concept of a consequence, you do something which in return have some sort of consequence.

    Not with me, I am NOT able to visualize the consequences of my actions, EVEN THOUGH I am VERY aware of what the probable outcome will be, this has driven me into SO MANY problems in my life, you CANNOT imagine what I have been through.


    I had a gambling issue at one point, I was playing a lot of online roulette and blackjack, you might already now know that I did not become very rich of this, in fact "I had no problem" spending upwards of $600 dollars on these games, I did this WELL AWARE that I would likely need these money later on, and it obvously turned out right, however it felt like I was completely missing something that made me stop, you might call this an addiction or not, but this is when it gets interesting, what made me stop, was a person, which I was in love with, that told me to stop because it was not doing me good, and I have not spend a single dollar on these games ever since, I have not even had the urge to do it again.

    Now this is just a tiny fraction of my problems, this is when it gets crazy;

    I can only assume that a "normal brain" is able to process ONE thought / idea at a time, I hear people say all the time "I have so many thoughts in my head" – I imagine these thoughts passing through, one at a time, leading someone to say "I have many thoughts".

    Well, in my brain, I can have a MULTITUDE of thoughts simultaneously, this is what I often describe as having "noise" in my head, if I had to describe it as a sound, and not a feeling or "thinking", I would describe it as having 10 TV's on 10 different channels constantly talking and I spend a lot of energy making out, what the fuck I am thinking at, things like Nicotine (I don't smoke but chew) Caffeine etc, tends to "smooth" this out to a much more manageable level but it never goes away, sometimes I can't even fall asleep because of this.

    Add in to the mix, not being able to "Filter" external sounds, this almost feels like a superpower to me, in any given environment, I hear every single sound produced in said environment, if I am outside, I hear every single car, bird, footstep, conversation, raindrop – whatever it might be, there is no "silence" in my world, and as if that was not enough, I have the same "Problem" with my vision, I see EVERYTHING, even if I am not looking directly at it, I notice any single movement in my full angle of view.
    – Yet somehow, classical music takes it all away to a certain degree, I REALLY enjoy classical music for this very reason, and have since I was 11 – 12 years old.

    And these things are SO hard to explain to people who do not have ADHD because their brain works DIFFERENTLY chemically and physically.

    And it is especially hard for some (Normal) people to believe me because besides all these things, I am intelligent well above average and are extremely gifted in some areas, especially socially and musically, even though I don't work very well socially.

    I also seem to have extreme difficulties doing everyday tasks, while some ADHD people have "tools" to help them through the day, I for some reason seem to have MUCH greater trouble doing the same thing, my short term memory is basically NON-existent, however, I have NO problem helping OTHER people with the EXACT same tasks, even if they are not present.

    I could continue forever, sometimes I get up and walk to my kitchen only to completely forget why I did it, then I just stand there trying to make out what I was doing.

    And people say this is a childhood thing (Thank god this is starting to change) but I am 26 years old!!

    I used to smoke weed, because for some odd reason, weed takes away almost ALL of the above symptoms, but it also makes me even less motivated, and it is already hard enough for me to even get the feeling of motivation, I assume this is due to the lack of dopamine production/receptors, I have stopped smoking weed obviously as it did not help me long-term.

    My point is, THERE IS SO MUCH we do not understand about ADHD that I feel like the word "ADHD" does not do justice for whatever it is that my disorder is doing to me.

    I'd also like to underline that I DO NOT suffer from anything else, I do not suffer from OCD, Schizophrenia, PTSD, or whatever my symptoms MIGHT also sound like, I am pure ADHD and are, besides all this crap, "normal" functioning person.

    I almost forgot to mention the Hyper-Focus, this is just crazy I don't even know where to start, but I'll leave you with this, I WISH a normal person could experience Hyper-focusing somehow because it is really beautiful.

  6. its not about how fast illicit drugs work compared to how slow medications work, mehtamphetamine can be used to treat add as the brand name desoxyn, its the dosage that sets treatment from recreation apart, a recreational dose of any amphetamine whether pharmaceutical grade or illicit, triggers euphoria

  7. This video mentioned methamphetamine. I'm aware of it's use as an illicit drug, but was also made aware (due to an insurance company's formulary list) that methamphetamine (brand name = "Desoxyn") is used for ADHD treatment. Does this form of the drug cause a slower neurotransmitter release than the illegal form (and some of it's ingestion routes) or is it the chemical itself that governs the rate of neurotransmitter release?

  8. This is not up to-date with the current DSM, actually hyperactivity is simply a stage of the developmental disorder. Children tend to always have hyperactivity, and as we get into adulthood hyperactivity is more associated with an anxiety disorder then with add.

  9. So what's the disorder called for people who actually like sitting still for hours on end focusing on pieces of paper or giving undivided attention to other people talking at them?

  10. Wrong I have ADHD and it's different like what ADJD have an H in it for a reason! ADD doesn't because they aren't hyper they are different ADHD is you can be very hyper and stuff and you can't focus

  11. my parents treated my adhd (which was diagnosed at age 14) by saying, "I dunno, try harder," and then not taking me to therapy anymore.

    [spoiler] I still struggle with it a lot. [/spoiler]

  12. Great video! I just wanted to comment on the psychopharmacology part at the end. Just clarification but, dextroamphetamine, actually has a shorter biological half life than methamphetamine. The distinct difference in recreation vs clinical effects has more to do with the route of administration of the drug. Smoking crystal meth results in a very quick euphoric effect, while oral methamphetamine (in reasonable doses of course) is much less euphoric and approved as a treatment for ADHD. This also has to do with why extended release medications are generally well-received when treating ADHD.

  13. Hi! I am a young girl, I believe I have ADHD, it is horribly affecting me at school as well as at home and in life in general, and I cannot go on like this anymore. I have all of the symptoms of ADHD/ADD but have not been able to seek a diagnosis. I have talked to my parents a little, but they don't know how to go about getting evaluated and diagnosed, and neither do I. I don't know what kind of doctor I have to see and what kind of testing I would need to possibly get diagnosed. What can I do, these symptoms are so hard to go through and I need help. Thanks!

  14. Would have loved to see this too: Dextroamphetamine is only one molecule used. A lot of people, especially those living in countries where ADDERALL is not available, have heard of Ritalin and the newer, Concerta which are generic name for the molecule Methylphenidate.

  15. I wanna contest an idea you present at around 5:00. I don't think you're wrong, per se, but the way you present the difference in effect between amphetamine and N-methyl-amphetamine is misleading at the very least. The idea that amphetamine provides a slow release of dopamine while meth provides a rapid one is a bit misconstrued. This difference in the pace of release has less to do with each compound's respective chemistry and more to do with the route of administration commonly used for each. Meth is usually smoked. Absorption through the lungs provides a very quick route directly to the bloodstream whereas oral administration (typical for medical amphetamine) naturally yield a slow release because the compound must be absorbed through the walls of the stomach. Meth does have a bit of an easier time crossing the blood-brain barrier, but this only has a marginal impact on the rate of dopamine release.

  16. I've never been to a psychiatrist, but many of these symptoms can still hinder performance even when it's not a full disorder. Personally I only noticed this in med school where many students can focus for so long and I can't spend more than 10 minutes reading a text book. Videos and role playing in my head are the reasons I am passing 😀
    I don't want to be diagnosed and treated with stimulants to be dependent on them, but there is always that thought in the back of my head that says: What if? how fucking sick will my performance be if I did? Just a small share, good luck to everyone with ADHD, the struggle is real =/
    Also I believe that my symptoms are always at mild to moderate because I have always worked out or exercised since early childhood. Maybe that gives me a constant little Dopamine boost

  17. Funnily enough my eldest brother has Autism & Dyspraxia while my middle brother has ADHD….. and guess who has all 3 of those and more? Me, the baby in the family. Fun times

  18. I hate having ADHD I can barely focus because of it. My dad heard I got diagnosed with it and gets mad at me when I can stay still. He always says i have a problem. It'd very stressful.

  19. I get ADD when I find something boring but as soon as something that interests me comes along it magically clears up.

  20. Isn't the infamous Adderall one of the main medications used to treat ADHD? It contains amphetamine salts, which ARE the same as the illicit drug amphetamine. That does not warrant so stark distinction between illicit stimulants and medicinal chemicals as stated in the IMO.

    Let me just also say that I absolutely adore the videos you are producing and make sure it spreads to everyone!

  21. It took me 20 minutes to watch this. I kept on having to scoll back. Am 28 and have struggled with ADHD all my life. What makes it worse is that am in Kenya. getting treatment here is bloody expensive. But am optimistic that i will manage it. And if i get a child, i will know how to support them. I will nevet let them go through the hell i went through as i was growing up.

  22. "ADD is an outdated term used prior to 1987, after which it evolved into ADHD to encompass more of the symptoms people with ADHD often experience; which, in addition to being inattentive, includes both hyperactivity and impulsiveness" thank you for that line, I'll have to remember that whenever people start crossing the two

  23. Ok, this is for every parent who think that, their kid might have add or adhd;

    First of all, before you tag your child as "just lazy" and ruin his/her life forever, take him/her to a psychiatrist. They can accurately diognose if your child really has that disorder or not. Nobody is capable of dealing such a mental disorder without professional help or even medication.

    Having ADHD doesn't mean your'e crazy or stupid. Vast majority of ADHD patients are advanced intelligence people. Their only problem is getting super bored while studying. So bored that they can't help theirselves, no matter how bad the situation is going. They just can't beat it.

    But with a simple treatment, they can. You'll be surprised how quickly they'll become succesful after their treatment begins. We're living in the 21st century for God's sake, stop the ignorance!

  24. Quite ironic bc I found myself not paying attention like half way through this, not saying this was boring but I think you said something and I went off in a tangent in my mind lol

    My parents actually took me to get tested for ADHD/autism when I was little bc I was like 3/4 and I still couldn’t speak or make eye contact properly, but turns out I’m fiiiiine and I eventually learnt. Though I do wonder sometimes if they got the diagnosis wrong bc I’m starting to notice my inattentive-ness more and more lol

  25. Changing ADD to ADHD to all people who suffer from attention deficit is extremely flawed. There are people, especially children, who may daydream and drift off task in school, to the point where it's detrimental to them, but still not be hyperactive or exhibit behavior problems (other than not finishing their school work) .

  26. Is ADHD a stigma?
    what if it is affecting your daily life,just because you cannot focus and cannot arrange your data but you know what information you have to collect but how to present it in a handsome know about this topic but you seems to be a dumb infront of audience …..all this triggers lose of confidence.It hinders your efforts to be a successful person.all this is just do not know what you have to do how you have to do n then your parents are not willing to help you
    you keep on telling them about your problem.They are not willing to listen to you.all this is considered as overthinking.

  27. My doctors think that I got ADHD bc when I was a baby up until I was 2 and a half I spent in and out of hospitals and the doctors had to keep me on anesthesia most of the time and the think the amount of anesthesia in my system caused my impulsivity or ADHD

  28. Hi! I'm studying psychology and I've found this video and the one about autism spectrum disorder REALLY helpful for a subject I have called "Neurodevelopmental disorders". I was wondering if you could do videos like this for Communication Disorders (Specific Language Impairment and Speech Sound Disorder) and for Specific Learning Disorders (Dyslexia and Dyscalculia).
    I would really appreciate if you could do it because you summarize all the areas (DSM, causes (genetics+environment), definition, symptoms (cognitive+behavioural+neurological) and treatment) that are explain in my manuals and in my lectures.
    Thank you very much! and again, congratulations ^^

  29. those who have adhd will NOT live a more fulfilling life than if they were to live in a society that does not see it to be a disorder nor a problem. why watch a guy being stabbed. why would someone force you to watch it. like that chicken in {robotchicken} on adult swim- you think that chicken has adhd? no. he doesnt. he souly wants to gtf out of that chair because it does not suit him. we live in a society where we should be forced to suit what society believes we should be suited for. in elementary school, there should be dozens upon dozens of classes needed for this world. every child, every day should have to go through each corse like 15 minutes a day. if anything, 28 classes for 1st through 5th grade. then 14 classes for 30 min each at 6-8th grade. 7 classes for an hour each for 9-12th grade. 1-5th grade should have 140 classes. all based on what interests us to survive our boredom. then 6-8th grade should have 42 classes that teaches more in depth about the topic you find interesting. there should be MANY schools that teaches different subjects. if you like something,, you should go to a different school to learn it further. no school 6-12th grade should be teaching the same thing. that's just dumb. does anyone understand me? anything out there?

  30. My mother doesnt go easy on me for having adhd. She does not understand how much of hell i go threw everyday sitting on chairs for hours and hours on and struggling to finnish assignments. She argues with me everyday because i cant put on my clothing correctly or i cant find important school items. Im happy that you guys out there are getting the proper care that you need. God bless.

  31. Well what if someone’s talking to you and you hear but you don’t process it like it goes in one ear and out the other. I think it’s part of the fidgeting and distractedness that’s what I have I am diagnosed with ADHD

  32. I think my mom said something like I was diagnosed at 2 years old I have ADHD and hyperactivity and the medicine I was taking gave me Tourette's

  33. “She is absolutely brillant! But she needs to pay attention in class more and needs to work on her time management and organizational skills so she doesn’t make careless mistakes.” – Every Teacher I Have Ever Had. They just don’t get that they are asking the impossible

  34. My son was misdiagnosed with adhd and autism. He actually had atlas bone dislocation/subluxation. It caused similar symtoms as it put pressure on his brainstem. His nerves, spinal fluid and csf pressure increases. We did all the medical care, drugs and therapies….none worked. He got his spine adjusted and he went back to normal. Save yourself time and avoid drug risks by trying atlas orthogonal or upper cervical care. It just could help you too. Im a RN who never guessed a chiropractor could cure my kid…but he did thanks to a prayer to God for help

  35. Hmm, I'm not doubting the genetic component by any means, but I do wonder if in these studies they accounted for the fact that siblings are most likely seeing the same provider as one another. Could at least a portion of the higher incidence of the disease in siblings/twins be attributed to a provider who more liberally applies DSM criteria in making a diagnosis? Or partially attributed to the studies being based on children whose parents are more likely to see a doctor about their child's focus and energy rather than handling it a different way? Sibling/twin studies are an amazing tool I know, but it's just interesting to me that it might not be as clear cut with self reports and subjective assessments of constructs like attentiveness and impulsiveness as it would be with other diseases that have clear objective pathophysiological criteria. If you have thoughts on this, feel free to let me know! Even if it's telling me why I'm wrong (maybe even especially if it is)

  36. ADD and ADHD is not the same. Like your example with twins, ADD & ADHD have many similarities but are not the same person.

  37. boring i cant focus so maybe i have adhd i dont know but i am very hyper active person who can function very well at work with very little sleep and i do alot of sports because i have too much energy. sometimes i wish i was a calm person but im so hyper and talk too much how do i calm down?????

  38. I have ADHD, and usual symptoms are Hyperactivity, Impulsive, sometimes OCD, forgetfullness, scanning over words while reading, and much more. Thanks for the video, i learned more about my disorder.

  39. ADD and ADHD are not the same thing. ADD is a SUBTYPE of ADHD, so it's basically ADHD without the hyperactivity. It's not and outdated term and i personally have ADD

  40. I was diagnosed with ADHD at the age of 4 years old and I am now 13 years old and it still affects me even though I take medicine

  41. You know what sucks is that multiple of my teachers say I have bad hdhd and I have never been tested for it I have to sometimes use a stress ball or a fidget cube. Last year I used to get bad anxiety which comes with hdhd and I had to use a stress ball the whole year also when I was fourth grade I got to use a fidget spinner which that helped me a lot but my school banded them and it wasn’t fair. The only thing is I get good grades but have a hard time focusing and I’m better off learning it by myself. Also I’m an introvert and I’m shy and have social anxiety.

  42. Sometimes I move so much that it's hard to go to sleep.

    Even in this comment when im typing something or saying something a thought just pops up and i realize what I was doing and try to concentrate back.

    I'm always thinking about everything, it just never stops, its a torture.

    Do you guys think I have ADHD? I have more symptoms, but I just can't concentrate right now, my thoughts are all over the place today (happens some days like now) I'm 14

  43. When a child with ADHD going very hyperactive, is their movement influenced by the conscious nerves? Or by the unconscious nerves?

  44. I have adhd for 2 years now and I didnt even know the hyperactivity exist . Then i went to doctor and i was diagnosed with s
    4 mental disorders I was so surprised lmao hahahahahah xD
    I got
    Psychosis ( Major Depression Disorder )
    Intermittent explosive disorder

  45. I think that people use ADD/ADHD as a joke. I’m 13 and I was diagnosed with it. It physically hurts to sit still or to not make any movements

  46. Whenever I’d throw a tantrum bc I didn’t want to do chores my parents would always say “I wanna take you to a doctor one day bc there’s gotta be something wrong with you! 😡”

    Now I wish they had taken me to get checked for this. :/

  47. I have a hard time with people bc they tell me that bc I take adhd medicine that I’m a drug addict and I’m on METH! It’s upset me so bad that I went to my pharmacist and asked her was I on meth.. she explained to me the DIFFERENCE between the two! This STIGMA around medication has to STOP!

  48. There is no reason to discuss methamphetamine in a discussion of adhd and further calling it illicit . Both d-amphetamines and methamphetamine are schedule 2 drugs. The schedule is a political statement rather than a scientific one. Most all of these drugs are in nature and have coevolved. Euphoria also is produced by adderall. It is not an illicit condition.

  49. I have ADD… so does that mean i have ADHD??? 🤔 also medicene for ADD sucks… it makes me tired. like if u agree

  50. After 2 min of the video I continued looking on it but my thoughts were with electrical scooter. I have ADD, just saying 😀

  51. Why the fuck no focus is given to vaccination as a principal cause of all this shit happening to our kids? Strong recommendations to keep mouth shut?

  52. Very cool! Very clear! 
    Anyone else interested in looking at ADHD with another angle? The system is designed for people without ADHD, right? How would a school, a research team, or a company look like if it were to embrace the capabilities of people with ADHD instead of trying to put them in this 'normal' box?

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