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What is ADHD?

Attention-deficit/hyperactivity disorder (ADHD)

If you’ve ever been to a child’s birthday party, the term hyperactivity will be familiar to you. Kids can be a whirlwind of running, giggling, yelling, poking, and interrupting fury. Although this energy can be exhausting for babysitters, parents, and teachers, it is a totally normal part of growing up. But for some kids (and some adults too!), the inability to control impulsive behavior or pay attention goes beyond the typical limitations of youth, and can cause serious problems at school, at home, and with friends.
  • Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental (related to the way the brain grows and develops) disorder defined by persistent problems with attention, organization, and/or hyperactivity and impulsivity that interfere with daily life or development.1

How do we pay attention, anyway?

Attention can be a tricky thing. Most of us feel like we can choose what to focus on and what to ignore. Email from cute coworker: Pay attention! Email from boss: Ignore! While choice certainly plays some role in attention, the majority of our focus happens without us even trying.
Try this: sit as quietly as you can for 30 seconds. Wherever you are, pay attention to your surroundings. What do you notice? A ticking clock, a buzzing light bulb, an itch on your leg, a conversation in the distance? These things are all around us all the time but we usually don’t notice them.
We only have so much attention to give at any one time. So, when we choose to pay attention to something (like reading), we rely on our brains to automatically filter out things that could distract us (like a buzzing light bulb). Scientists have identified several areas of the brain that work together to make this possible.
  • Prefrontal cortex: helps with making plans and controlling inappropriate behaviors
  • Basal ganglia/striatum: helps with motivation and choosing between different possible behaviors
  • Cerebellum: helps process information and control our movement
  • Corpus collosum: helps with integrating information from different parts of the brain
Diagram of lateral brain section
By working together, these areas of the brain allow us to choose what we want to pay attention to.
But what if our brains didn’t do this very well? What if, while you were trying to read this sentence, you were also noticing the ticking clock, and the buzzing light, and the itch on your leg, and the other conversation? It would be very difficult to get through the rest of this article.
You can think of the hyperactivity and impulsivity associated with ADHD in the same way. Some things we definitely choose to do (going to the movies) but most of our behaviors happen without much thought (you don’t have to think “I choose not to get up during the movie and run around the theater”, you just don’t do it). Because our brains automatically inhibit us from doing things we’ve learned are inappropriate, we are free to use our mental effort to make harder decisions. However, when our brains aren’t as effective at automatically eliminating possible choices of behavior, we can act on an impulsive behavior before we have had time to think about whether or not it is a good idea.
The same brain regions that are important for attention also help us control our impulses. That’s why, in the case of ADHD, atypical functioning in the brain areas mentioned above can lead to problems with attention, hyperactive/impulsive behavior, or both.

What are the symptoms of ADHD?

The symptoms of ADHD begin in childhood (usually between ages 3 and 6), and for about 50% children, continue into adolescence and adulthood. The primary symptoms of ADHD fall into two categories: inattention and hyperactivity/impulsivity. While these symptoms can be present in children or adults, the specific presentation of symptoms is usually different at different ages.
InattentionFailing to pay attention to details that leads to careless mistakes
Often not seeming to listen when being spoken to directly
Often having difficulty with sustained attention, organization, follow through
Often easily distracted
Hyperactivity/impulsivityConstant fidgeting, tapping hands or feet, squirming in chair
Often leaving seat when sitting is expected
Often talks excessively
Often interrupts or intrudes on others

How is ADHD Diagnosed?

ADHD is not diagnosed by a simple test or interview. Because most people experience the symptoms of ADHD sometimes, it’s very important for health care providers to talk to the parents/caretakers, teachers, friends, and coworkers of anyone being assessed for ADHD, to better understand how the symptoms affect different areas of a person’s life.
To be diagnosed with ADHD, the symptoms must be present in more than one setting (e.g., at school and at home), continue for more than six months, and must be significantly worse than what would be expected given the person’s age. Other conditions (like oppositional defiant disorder, intellectual Disability, or substance use disorders) need to be ruled out before a formal diagnosis of ADHD can be made.
There are three subtypes of ADHD. These subtypes are based on whether a person has inattentive symptoms, hyperactive/impulsive symptoms, or both.
Venn diagram of types of ADHD

What are the causes of ADHD?

The exact cause of ADHD is unknown, but developmental differences in areas of the brain responsible for attention and behavioral control are thought to be involved.2 These differences can be caused by the genes we inherit from our parents (ADHD runs in families), damage from exposure to toxins (like lead, cigarette smoke, and alcohol in utero), or other factors (premature birth or head injury).
Surprising to some, the vast majority of research suggests that things like eating too much sugar, watching too much television, or living in a chaotic household do not cause ADHD.3 These things may lead to problems with focus or attention, but that is different from having ADHD.

How common is ADHD?

ADHD occurs in most cultures, and affects about 5% of children and 2.5% of adults worldwide.1 ADHD is particularly common in the United States, where childhood prevalence has been estimated to be as high as 11%. Males are twice as likely as females to be diagnosed with ADHD, but females are more likely to have the inattentive subtype. Rates of ADHD are on the rise in many counties. It is not known whether this rise is due to an actual increase in the number of people with ADHD, or if ADHD is just being diagnosed more often (either by better recognizing ADHD where is exists, or by falsely diagnosing ADHD where it doesn’t exist).

Can ADHD be prevented?

Because the exact cause of ADHD is unknown, it is unclear what can be done to prevent it. With that being said, taking steps like avoiding drugs and alcohol (or other toxins) during pregnancy may reduce a child’s risk of ADHD.

How is ADHD treated?

Although there is no cure for ADHD, there are several treatments that can effectively reduce symptoms. ADHD is typically treated through a combination of medication, behavioral therapy, and family and school education.
  • A class of medications called stimulants is often used as a first step in treating ADHD. Stimulants work by increasing the amount of the chemical dopamine that is circulating in the brain. For people without ADHD, this surge of dopamine is very energizing (that’s why drugs that release dopamine are called stimulants!). Ironically, for people with ADHD, the increased dopamine seems to be calming and can help improve focus and behavioral control. Common side effects of these medications include reduced appetite and trouble sleeping. Medications work well to reduce ADHD symptoms right now, but unfortunately do nothing to reduce future symptoms (as soon as the pills wear off, your symptoms return).
There is some controversy about whether it is appropriate to treat children with stimulants (after all, cocaine works by releasing dopamine too). While the decision to use medication is a personal one that should be made with the assistance of a healthcare provider, stimulant medications have largely been found to be safe and effective in reducing the symptoms of ADHD.
Behavioral therapy:
  • Behavioral therapies focus on developing skills and strategies to counteract the symptoms of ADHD. These skills can range from practical things like organization and studying tools, to social skills training (understanding other people’s emotions, waiting your turn, etc.). Through working with a therapist, a person with ADHD learns to focus on the consequences (both good and bad) of their actions, which can help reduce hyperactivity and impulsivity. Behavioral therapy works well to reduce the problems caused by ADHD in the future, but doesn’t work as well as medication in reducing symptoms right away.
Family and school education:
  • Living or working with someone with untreated ADHD can be very difficult. Particularly for parents and teachers, dealing with the symptoms of ADHD can lead to frustration, guilt, anger, and exhaustion. These feelings can actually lead to even worse outcome for the person with ADHD. For example, a child with ADHD who is having trouble sitting still in school (at risk for poor academic performance) is constantly sent to detention because his teacher is frustrated by his distracting behavior (putting him at even greater risk for poor academic performance). Working to educate families and teachers about how to manage the needs of a child/student with ADHD is a very important part of treatment.

Consider the following

ADHD can be found all over the world, but it is most prevalent in cultures that have required schooling for all children. Why might that be? (Hint: It probably isn’t that elementary school is causing ADHD). You can think of attention or behavioral control just like any other trait humans have: some people can naturally do it very well, others not so well. While these abilities may be mostly unchangeable, they are only helpful/hurtful in certain situations.
For instance, some people can fold their tongue like a taco, other people can’t. However, not being able to fold your tongue isn’t harmful, because you’ll probably never be put in a situation where the skill of tongue-folding will be required to succeed (ever been asked to fold your tongue in a job interview?).
Cultures with required schooling commonly put kids in situations (classrooms) where skills like attention and behavioral control are very important to success; making poor performance in these areas much more noticeable and problematic. This leads to higher rates of ADHD diagnosis. When you are thinking about ADHD, keep in mind that it’s not just the brain differences that determine how harmful the symptoms are, it’s also the situation.

Want to join the conversation?

  • piceratops ultimate style avatar for user Alexis  Harrington
    If ADHD impacts 5% of kids and only 2.5% of adults, does that mean some people grow out of ADHD?
    (7 votes)
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    • leafers ultimate style avatar for user geordini.marzan
      A problem in math in here. There is a bigger population for the category of adults than kids. That's only a percentage. Research for the actual figures for each age level. In addition, there is an increasing incidence of ADHD each year for children developing the condition which could as well explain your concern. Also, symptoms of ADHD can be managed through behavioral therapy and medications. Cures are yet to be discovered.
      (8 votes)
  • female robot grace style avatar for user Lala
    Is it possible for someone to have mild ADHD? For example a kid who doesn't really have problems sitting still but still notices a lot of things around them, but kinds of things kids without ADHD wouldn't really pay attention to.
    (7 votes)
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    • duskpin ultimate style avatar for user poultrymaniac
      I will look into that for you. to be honest I'm curios about that too.
      (a few minutes later.)
      Google has a list of symptoms, and it list stuff like anxiety, short attention span, hyperactivity,
      impulsivity, aggression, etc. you might want to take a look at it your self.
      so I think mild ADHD is possible, just like mild phobias are possible. imagine it like salsa.
      there's mild, medium, spicy, and super spicy. how severe it is varies.
      There are kids who are simply more active than normal, yet not hyperactive. And some people are great at noticing things. If you don't have ADHD and are still easily distracted, you may just have more sensitive senses.
      (8 votes)
  • blobby blue style avatar for user Ivy
    But how do we know that some people who are diagnosed are just simply, you know, active, and learn better with hands on work, or doing more than just sitting when they learn? And another symptom of the medicine, isn't it depression?
    (6 votes)
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    • leafers ultimate style avatar for user geordini.marzan
      There are diagnostic criteria to meet. Below 17 yo children need to meet at least 7 sxs while people older than 17 need to meet at least 5 sxs that persisted for at least 6 mo. Check DSM 5 for the list of the symptoms. There are some psychological tests and behavioral assessment that are needed to be conducted too. Also, there is a chance that the child has developed another disorder other than ADHD. We cannot set aside that possibility.
      (3 votes)
  • hopper cool style avatar for user Madeliv
    Is the difference between diagnosis of boys and girls ("Males are twice as likely as females to be diagnosed with ADHD, but females are more likely to have the inattentive subtype.") due to problems with diagnosing girls or is there a genetic reason making boys more susceptible?
    (3 votes)
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    • primosaur ultimate style avatar for user greensock
      There's not definite answer, but boys with ADHD are more likely to act out based on it, therefore more likely to be diagnosed. There's also a theory that ADHD has something to do with a problem which an X chromisome, which females have two of as a sort of 'backup'.
      (3 votes)
  • male robot hal style avatar for user Ayden Wyatt
    I found this article very helpful, all of it. My parents do sometimes get frustrated. I tend to ask "non-appropriate questions". It was hard for me to focus on this article, but if anyone knows of good ADHD medicine, please tell me... I am currently taking 20 Milligrams of Methylphenidate.
    (1 vote)
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    • blobby green style avatar for user RedMapleTreeLeaves
      I have ADHD as do my 3 siblings and my 3 kids so I'm happy to relay what I know about the various medications and how I've seen them work. Questions, were you on your medication when you read the article (how recently had you taken them)? Do you feel your medication is helping you at all? How long have you been on the medication? Im assuming your daily dose is 20mg and you take 10mg twice a day but correct me if Im wrong. This medication lasts 3 - 6hrs so does it last you all day? I was on this as a child 10mg 3xs a day, but the dose depends on the person. For example a petite lady may need 70mg, where as a 6ft solidly built man is perfectly happy taking 30mg. The other main type of ADHD medication is Dexamphetamine. From my experience if you are not seeing or feeling an improvement in your ADHD, basically if life hasn't gotten any easier in all the ways you previously found it really challenging, then your medication needs to be reviewed. There are long acting versions of these medications as well which means you only take one tablet a day, plus there is no forgetting a dose or leaving it too long between doses. Personally I take Vyvanse which is the long acting version of dex and it is amazing. It takes about an hour to start 'working' which is annoying consider the short acting stuff only took 10mins, but it lasts 12hrs. From me getting back on my ADHD meds after being without them for many years, I got my 3 siblings back on their meds even though they were convinced they didn't need medication. My own children also have ADHD and we started on Ritilian ( methylphenidate) which was ok and then we tried Concerta, the long acting version of it but that was worse than them taking nothing. Everyone in my family has ended up taking Vyvanse. I still say/ask "inappropriate things" off my meds ;) Talk to your parents and your Doctor about your medication. You might find this helpful/interesting to understand more about how your ADHD http://www.drthomasebrown.com/add-adhd-model/
      (5 votes)
  • duskpin ultimate style avatar for user Dakota Spencer
    can you grow out of adhd as you get older caue i have adhd and i am having a hard time focusing on typing this question and reading this article
    (3 votes)
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  • aqualine ultimate style avatar for user a cat taking a bath
    Is speaking nonsense and crying and/or whining part of ADHD?
    (3 votes)
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  • blobby green style avatar for user isaac.aboagye1978
    Is there a certificate for ADHD
    (2 votes)
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  • duskpin ultimate style avatar for user poultrymaniac
    I am homeschooled, and it occurred to me that maybe there are kids with
    ADHD, and do not know it because they are home schooled. Is this possible?
    And could homeschooling be part of a solution for ADHD?
    (2 votes)
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  • starky sapling style avatar for user luke.273394
    Is ADHD diagnosed at birth, or can it be developed?
    (2 votes)
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