What is ADHD?

ADHD vs. ADD: Genetics, IQ, Rates in Kids & Adults

ADHD, previously known as Attention Deficit Disorder (ADD), has been recorded in medical literature dating back to 1904. However, it is believed that the condition existed long before then, as it has a strong genetic component.

If you have a close relative with ADHD, there is a higher probability that you will have it as well. For example, if you’re an identical twin and your twin has ADHD, there is a 75% chance that you will have it too.

The genetic component of ADHD relates to how specific neural circuits in the brain wire up, the chemicals they use, and the way they use those chemicals.

It’s important to note that having a close relative with ADHD doesn’t mean that you are destined to have it.

Additionally, having ADHD doesn’t mean that you have a low IQ. There are people with ADHD who have low IQs, people with ADHD with high IQs, people with ADHD with high emotional IQ, or with low IQ in the emotional scale. The ability to attend and focus does not relate to how smart you are or your IQ of any type.

In the mid-to-late 1980s, the psychiatric and psychological communities started to take better notice of the fact that so-called hyperactive kids also had attentional issues.

This led to the renaming of ADD to ADHD. This renaming has led to much better diagnosis and detection of ADHD.

Currently, the estimates are that about one in 10 children, and probably more, have ADHD. Fortunately, about half of those will resolve with proper treatment, but the other half typically don’t.

Another trend that is being seen nowadays is increased levels of ADHD in adults. It is not clear whether these adults had ADHD that went undetected during their childhood or whether ADHD is now cropping up in adulthood.

Regardless, it is important to note that ADHD is a condition that can affect individuals at any stage of their life and proper treatment should be sought if symptoms are present.

Attention & Focus, Impulse Control

First, let’s define what we mean by attention. In the scientific literature and discussions about ADHD, terms like attention, focus, and concentration are often used interchangeably.

For the sake of this discussion, attention, focus, and concentration are essentially the same thing, unless specified otherwise.

Individuals with ADHD have trouble holding their attention. Attention is defined as perception, or how we perceive the sensory world.

Our nervous system is constantly sensing things, but we are only paying attention to some of them. Attention and focus are more or less the same thing, but impulse control is something separate.

Impulse control requires pushing out or putting the blinders on to sensory events in our environment. It means lack of perception.

People with ADHD have poor attention and they have high levels of impulsivity. They are easily distractible, but the way that shows up is very surprising.

One might think that individuals with ADHD simply can’t attend to anything and they can’t focus, but that’s not the case.

Time Perception

People with ADHD often have challenges with time perception, which can lead to running late, procrastination, and difficulty completing tasks. However, it is important to note that if given a deadline, people with ADHD can perceive time very well and can focus very well if the consequences of not completing a task or not attending are severe enough.

It’s similar to how people with ADHD can focus well if they like something, if they’re scared enough about the consequences of not attending, they can attend.

However, if they’re not really concerned about a deadline or consequence, they tend to lose track of time and underestimate how long things will take. This is a common problem not just for people with ADHD, but for many people.

People with ADHD often have trouble understanding how to line up the activities of their day in order to meet particular deadlines, even if it’s just a simple thing like finishing one set of tasks before lunch.

They may remember that lunch starts at noon, but somehow they aren’t able to fill the intervening time in a way that’s productive. They can obsess about the upcoming deadline, but we will discuss ways to address this issue in future.

The Pile System

People with ADHD often have subpar spatial organization skills, and one way this manifests is through the use of the pile system.

The pile system is a way of organizing belongings in a way that makes sense to the individual with ADHD, but it doesn’t necessarily have a logical framework.

This means that they will take many belongings, and pile them up according to a categorization system that only makes sense to them.

It’s important to note that many people use the pile system, and if you use the pile system, that doesn’t mean that you have ADHD.

However, people with ADHD tend to organize things according to the pile system all the time, and that pile system doesn’t work for them. They can’t find things, or if anyone moves one thing, then it’s very disruptive to their overall plan because their overall plan doesn’t really work in the first place.

This is a common phenotype, or expression, of ADHD.

Working Memory

Working memory is the ability to keep specific information online, to recycle it in your brain over and over again so that you can use it in the immediate or short term. 

For example, if you meet someone and they give you their phone number verbally, you have to walk back to your phone and enter it into your phone. 

People without ADHD might have to put some effort into it, but typically they would be able to recite that phone number in their mind over and over and then put it into their phone. However, people with ADHD tend to lose the ability or lack the ability to remember things that they just need to keep online for anywhere from 10 seconds to a minute or two. 

This can make it difficult for people with ADHD to remember information such as phone numbers, sentences or instructions. 

Deficits in working memory are also something that we see in people who have frontotemporal dementia, so damage to the frontal lobes or age-related cognitive decline.

Interoceptive Awareness 

Interoceptive awareness is the sense of one’s own internal state, such as heartbeat, breathing, and contact of skin with a given surface.

For a long time, there was a hypothesis that people with ADHD were not in touch with how they felt and that if they could just learn to attend to their internal state better, they would function better in the world.

However, recent studies have shown that people with ADHD are aware of what’s going on inside them just as much as anyone else is.

A study titled Interoceptive Awareness in Attention Deficit Hyperactivity Disorder explored whether interoceptive awareness was different in people with ADHD or those without ADHD and found that there was no difference.

The typical measure of interoceptive awareness is one’s ability to count their own heartbeats, which is challenging for some individuals regardless of their attentional capacity.

It’s important to understand that people with ADHD are in touch with how they feel and that it’s a question of whether or not they can take the demands that are placed upon them and enter a cognitive state that allows them to access the information they need to access.

In other words, whether or not they can focus.

It’s wrong to think that people with ADHD are unaware or oblivious to how they feel. They are challenged in the situations they’re in and are doing everything they can to try and regulate their attention.

The ability to coordinate task-directed networks and default mode networks is regulated by neurochemicals such as dopamine, norepinephrine, serotonin, and acetylcholine, which is vital for cognitive focus.

Attentional Blinks 

Attentional blinks are a phenomenon that occurs when our attention falters for a moment, making it difficult for us to spot certain objects or targets.

This can be compared to a “Where’s Waldo” task, where we search for a specific object among a crowded background, and once we find it, our attention blinks for a moment, making it difficult for us to spot another target that is nearby.

The concept of attentional blinks is important to understand when trying to improve our ability to focus.

A book by Daniel Goleman and Richard Davidson called “Altered Traits: Science Reveals How Meditation Changes Your Mind, Brain, and Body” discusses how attentional blinks can be reduced through meditation.

However, it is important to note that the author is not trying to convince the readers to meditate, he is just providing research data on the topic.

Attentional blinks can be studied in a laboratory setting by giving a person a string of letters or numbers and asking them to look out for specific letters.

When they spot the target letter, they tend to miss the next target letter that is nearby. This phenomenon highlights the importance of understanding how our attention works and how to improve it.

Blinking, Dopamine & Time Perception; & Focus Training 

When it comes to attention, our minds can sometimes shut off for a moment and miss important information. But did you know that our physical blinks can also play a role in how we perceive time?

We all know about spontaneous blinks, which are quick and coordinated between both eyes. But there are also long blinks that happen when we go to sleep at night.

These long blinks limit the amount of information coming in and as a result, our perception of time starts to drift as we go into sleep.

Our perception of time is also variable when we are in sleep. Sometimes we experience things in slow motion, while other times it’s very fast.

Similarly, in waking life, our experience of time can sometimes be very fast and other times very slow.

Typically, the more alert we are, the higher the frame rate, which means we are analyzing time more finely. For example, when we are stressed and waiting for something or someone, it seems like it takes forever because our frame rate is higher.

Conversely, when we are very relaxed or even sleepy, the world can seem like it’s moving very fast and we are moving very slow. Time is moving at the same rate, but our perception of time is what’s changed.

Interestingly, our perception of time is also changed on a moment-to-moment basis by how often we blink. This has been well-established in the field of neuroscience.

Unlike the literature and claims about blinking and sociopathy, which have no basis, the science of blinking as it relates to time perception has some very good data to support it.

One study, titled Time Dilates After Spontaneous Blinking, published in Current Biology, examines the relationship between fluctuations in timing and blinking.

The authors found that right after blinks, we reset our perception of time. Blinks, in this sense, are a bit like the curtain coming down on a scene between scenes in a play or takes in a movie.

What’s even more interesting is that the rate of blinking is controlled by dopamine. This means that dopamine is controlling attention, blinks relate to attention and focus, and therefore the dopamine and blinking system is one way that we constantly modulate and update our perception of time. And fortunately, it’s also one that we can control.

When dopamine levels go up, people tend to overestimate how long something lasted because they are processing time more finely.

It’s slow motion mode. When dopamine levels are lower, they tend to underestimate time intervals.

This is important to remember when it comes to people with ADHD, who are not good at managing their time and tend to run late.

Adderall, Ritalin & Blink Frequency

One of the major drugs that were developed and now marketed by pharmaceutical companies for the treatment of ADHD are Ritalin and Adderall. 

These drugs serve to increase levels of dopamine, in particular dopamine in the networks that control task-directed behavior and that coordinate the default mode network and these task-related networks.

But what happens when somebody with ADHD takes these drugs

It turns out they actually obtain heightened levels of focus. Their ability to focus on things other than things they absolutely care intensely about goes up.

One thing related to this whole business of blinking and focus and training yourself to focus and not blinking, et cetera, is that most all of the drugs, Ritalin, Adderall, and recreational drugs that increase dopamine, even coffee and tea and other forms of caffeine, they tend to make us blink less. And when we get tired, we tend to blink more. 

Now, this is sort of a duh, right? 

But being wide-eyed with excitement or fear or with your eyes barely being able to keep them open, now it should make perfect sense that these shutters on the front of your eyes, they aren’t just there for winking and they aren’t just there for cosmetic purposes. 

They are there to regulate the amount of information going into your nervous system. And they’re there to regulate how long you are bringing information into your nervous system and in what bins, how widely or finely you are binning time is set by how often you blink and how widely or specifically you are grabbing attention from the visual world.

Hyper-Focus & Dopamine 

People with ADHD are thought to be wild, hyperactive, and unable to sit still and attend, but this is not always the case.

Many people with ADHD, if given something they really love, such as a child who loves video games or an adult who loves a particular type of movie, will obtain laser focus without any effort. 

This ability is linked to the release of dopamine, a neuromodulator that changes the activity of the brain’s circuits.

Dopamine creates a heightened state of focus, contracts our visual world, and makes us pay attention to things outside of our skin. It also puts us in a state of motivation and wanting things outside of our skin.

Additionally, dopamine is responsible for changing the way we perceive the world. When dopamine is released, it tends to turn on areas of the brain that narrow our visual and auditory focus, while when there is less dopamine, we tend to see and hear everything all at once.

This tells us that people with ADHD have the capacity to attend, but they can’t engage that attention for things that they don’t really, really want to do.

Much of life, whether you’re a child or an adult, involves doing things that we don’t want to do.

Much of our schooling involves doing things that we would prefer not to do, and forcing ourselves to do it, to attend, even though we are not super interested in what we are attending to. This can be challenging for people with ADHD, as they have difficulty engaging with things that they are not genuinely interested in.

Additionally, people with ADHD often display other characteristics that can make it difficult for them to focus and attend.

Neural Circuits In ADHD: Default Mode Network & Task-Related Networks 

Let’s drill into this issue of why people with ADHD actually can focus very intensely on things that they enjoy and are curious about.

Now, enjoyment and curiosity are psychological terms. They’re not even really psychological terms. They’re just the way that we describe our human experience of liking things, wanting to know more about them. But from a neurobiological perspective, they have a very clear identity and signature, and that’s dopamine.

Dopamine is released from neurons. It’s what we call a neuromodulator. And as a neuromodulator, it changes the activity of the circuits in the brain such that certain circuits are more active than others.

And in particular, dopamine creates a heightened state of focus. It tends to contract our visual world, and it tends to make us pay attention to things that are outside and beyond the confines of our skin. It’s what we call exteroception.

Dopamine also tends to put us in a state of motivation and wanting things outside the confines of our skin. So whether or not we’re pursuing something physical in our world, or whether or not we’re pursuing information in our outside world, dopamine is largely responsible for our ability and our drive to do that.

But dopamine as a neuromodulator is also involved in changing the way that we perceive the world. As Huberman mentioned earlier, you have all these senses coming in, and you can only perceive some of them because you’re only paying attention to some of them.

Dopamine, when it’s released in our brain, tends to turn on areas of our brain that narrow our visual focus and our auditory focus.

So it creates a cone of auditory attention that’s very narrow. It creates a tunnel of visual attention that’s very narrow. Whereas when we have less dopamine, we tend to view the entire world. We tend to see the whole scene that we are in. We tend to hear everything all at once.

Hopefully you’re already starting to see and understand how having dopamine release can allow a person, whether or not they have ADHD or not, to direct their attention to particular things in their environment, right?

So now what we’re doing is we’re moving away from attention as this kind of vague, ambiguous term, and we’re giving it a neurochemical identity, dopamine, and we are giving it a neural circuit identity.

And just to put a little bit of flavor and detail on which neural circuits those are, let’s want to discuss two general types of neural circuits that dopamine tends to enhance.

Low Dopamine in ADHD & Stimulant Use & Abuse

The low dopamine hypothesis of ADHD was first proposed in a paper published in Biological Psychiatry in 2015.

The idea is that dopamine levels in certain brain circuits are too low in people with ADHD, leading to unnecessary firing of neurons that are unrelated to the task at hand. This can make it difficult for people with ADHD to focus on a task and pay attention.

When dopamine levels are low, certain neurons in the brain start firing when they shouldn’t be.

This can be compared to a band where one or several instruments are playing notes when they shouldn’t be. The pauses in music are just as important as the actual playing of notes, and in the same way, when dopamine is too low, neurons fire more than they should in the networks that govern attention.

Anecdotally, people with ADHD have been known to use recreational drugs or non-drug stimulants to increase their dopamine levels for decades.

For example, drinking multiple cups of coffee, smoking cigarettes, and using drugs like cocaine or amphetamine can all increase dopamine levels in the brain.

Even young children with ADHD may show a preference for sugary foods, which can act as dopamine-inducing stimulants.

It’s important to note that while these substances may help people with ADHD focus, they also have a high potential for abuse and should be used with caution.

Additionally, young children do not have access to these kinds of stimulants, and it’s important to find alternative ways to manage their symptoms.

Sugar, Ritalin, Adderall, Modafinil & Armodafinil 

It is commonly believed that children and adults with ADHD consume too many sugary foods or drink too much soda, or take recreational drugs like methamphetamine or cocaine, or drink coffee to excess or smoke cigarettes to excess because they have poor levels of attention and can’t make good decisions.

However, it is now understood that ADHD is caused by a lack of dopamine, a neurotransmitter that coordinates neural circuits that allow for focus and quality decision-making.

One theory is that individuals with ADHD are trying to self-medicate by pursuing compounds that increase their levels of dopamine.

For example, when children with ADHD consume anything that increases their levels of dopamine, they tend to be calmer and able to focus more.

On the other hand, children without ADHD who consume too much sugar or caffeine tend to become hyperactive.

This understanding of the role of dopamine in ADHD led to the development of dopaminergic compounds, such as Ritalin, Adderall, modafinil, and armodafinil, to treat ADHD.

These drugs increase levels of dopamine in the networks that control task-directed behavior and coordinate the default mode network and task-related networks.

While these drugs can be effective in treating ADHD, it is important to note that the use of these drugs should be under the guidance of a medical professional.

Additionally, the dosage and modulation of these drugs should be adjusted across the lifespan and in a specific way, as the brain’s neuroplasticity changes with age.

Non-Prescribed Adderall, Caffeine, Nicotine

The use of non-prescribed Adderall is alarmingly high among young people, with an estimated 25% of them taking the drug despite not having a clinical diagnosis of ADHD.

In fact, the use of Adderall without a prescription is now higher than the use of cannabis in that age group.

This trend highlights the ways in which people have always been self-medicating to increase focus and energy.

Caffeine, which is found in coffee and other beverages, has long been used as a stimulant to increase dopamine, norepinephrine and focus.

The active ingredient in coffee, caffeine, works through the cyclic AMP phosphodiesterase pathway, which helps to convert cyclic AMP into energy for cells.

Caffeine is consumed by many people for ages and it makes them feel good and increases their focus because of the circuits it engages in the brain.

In the past, people also used to smoke cigarettes, which contain nicotine, to gain focus. Nowadays, smoking is less common because of the concerns about lung cancer, but there is a lot of vaping out there and many people are consuming nicotine in order to be more focused and alert.

Nicotine is the active substance found in cigarettes and most nicotine vapes. The idea of taking stimulants, consuming things or smoking things in order to increase alertness is not a new idea.

How Stimulants “Teach” the Brains of ADHD Children to Focus

It’s surprising stimulants work with kids with ADHD. If the problem is attention deficit hyperactivity disorder, what we’re really talking about here or children that are prescribed a drug that ought to be a stimulant, it ought to make them hyper hyperactive. And rather than doing that, it actually somehow serves to calm them a bit or at least allow them to focus.

Here’s the reason.

Children have a brain that’s very plastic, meaning it can remodel itself and change in response to experience very, very quickly compared to adults.

Taking stimulants as a child, if you are a child diagnosed with ADHD, allows that forebrain task-related network to come online, to be active at the appropriate times. And because those children are young, it allows those children to learn what focus is and to sort of follow or enter that tunnel of focus.

Now, by taking a drug, it’s creating focus artificially. It’s not creating focus because they’re super interested in something. It’s chemically inducing a state of focus.

And let’s face it, a lot of childhood and school and becoming a functional adult is about learning how to focus even though you don’t want to do something.

In fact, when I was in college, I had this little trick that may or may not work for some of you, which is, if I couldn’t focus on the material I was trying to learn, I would delude myself into thinking that it was the most interesting thing in the world.

I would just kind of lie to myself and tell myself, okay, this, I won’t mention the subjects. I absolutely love this. I would just, I would tell myself that I loved it.

And I noticed that just that selective or deliberate engagement of that desire to know circuit, whatever that is in my brain, no doubt involves dopamine, allowed me to focus and remember the information.

And somewhat surprisingly, or perhaps not surprisingly, I would often fall in love with the information. I’d find that that was my favorite class. It was what I wanted to learn the most.

So that’s one way you can do it artificially, but kids with ADHD, they can’t do that, right? They’re told to sit still and they end up getting up 11 times.

You know, they are told that they can’t speak out in class or that they have to remain in their seats for 10 minutes. And they just, despite their best effort, they simply cannot do it.

They’re highly distractible. So what are we to make of this whole picture that we need more dopamine, but these kids with ADHD, they’re getting their dopamine by way of a drug, which is for all the world, amphetamines, right?

It’s speed. That’s really what it is. What are the long-term consequences? What are the short-term consequences? And what should we make of people taking these drugs without a clinical need? What are the consequences there?

Smart Phones & ADHD & Sub-Clinical Focus Issues In Adults & Kids

Smartphones are a technology that is affecting our ability to focus, not only for those with preexisting ADHD, but for everyone.

Smartphones are small and grab our attention entirely, but within that small device are millions of attentional windows scrolling by.

The brain is struggling to leave that rapid turnover of context, and it’s thought that this can lead to deficits in the types of attention needed to perform well in work and school relationships.

There are studies that have investigated the effects of smartphone use on attention, and one study in particular from 2014 found that in order to avoid a decrease in attentional capacity, adolescents need to use their smartphone for less than 60 minutes per day.

For adults, it is likely that the number is higher, with two hours per day being the upper limit beyond which attentional deficits can occur.

This constant context switching can lead to a decrease in our ability to do meaningful work and it is important to be aware of the time spent on smartphones, as well as to limit it in order to maintain focus and attention.

Cal Newport, author of the book “Deep Work” and “A World Without Email” has written extensively on the effects of technology on focus and attention, and suggests that the brain does not do well with constant context switching, and it’s important to be mindful of the time spent on technology and to be intentional with how we use it.

When To Medicate: A Highly Informed (Anecdotal) Case Study

Huberman spoke with one of his colleagues, a pediatric neurologist who specializes in the treatment of epilepsy and ADHD in children.

This colleague also has a young son who is showing signs of ADHD and is currently on the threshold of deciding whether or not to prescribe Adderall.

During their discussion, Huberman asked his colleague what they thought about giving young kids amphetamines.

The colleague’s response was that, on the face of it, it seems crazy, but provided that the lowest possible dose is used and that that dosage is modulated as they grow older and develop their powers of attention, they have seen more kids benefit than not benefit from it.

Huberman also asked why his colleague would consider giving medication now, as opposed to during puberty or after puberty.

The colleague’s answer was that neuroplasticity is greatest in childhood and tapers off after about age 25, but neuroplasticity from age three until age 12 or 13 is exceedingly high.

This early childhood plasticity is far and away the period when the brain is most open to change and learning.

By giving a child the ability to access stillness and focus early on, it is thought that they will be able to maintain that ability as they grow older.

It is important to note that Huberman is not a medical doctor and therefore cannot prescribe any medications.

He stresses the importance of speaking with your own doctor if you are considering giving Ritalin or Adderall or any type of stimulant to your child.

The health of your child is of the utmost importance and it is crucial to make an informed decision with the guidance of a medical professional.

Wrapping Up

ADHD is a condition that has a strong genetic component and can affect individuals at any stage of their life.

Symptoms of ADHD include difficulty holding attention, high levels of impulsivity, and challenges with time perception. 

It is important to note that having ADHD doesn’t mean that you have a low IQ, and proper treatment should be sought if symptoms are present. 

Modulation refers to the way in which certain factors, such as sleep and nutrition, support and regulate biological processes, while mediation refers to the direct control of certain processes by compounds like dopamine.

It is important to understand the distinction between the two when discussing treatment options for ADHD, as drugs like Ritalin and Adderall directly target the circuits and neurochemistries that mediate attention and focus, while behavioral alternatives and even diets can also be effective in modulating these processes. 

Open monitoring, a property associated with people who have done a lot of meditation, can also be used to improve focus.

Additionally, there has been an increase in ADHD diagnoses among adults, which may be due to the condition going undetected in childhood or cropping up in adulthood.

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Articles Mentioned

Review of Compounds for ADHD, Smart Drugs & Focus – https://www.fbscience.com/Landmark/articles/10.52586/4948

Review of Atypical Compounds for ADHD – https://www.hindawi.com/journals/np/2016/1320423/

Study of Focus Protocol In ADHD & Non-ADHD Children – https://www.mdpi.com/1660-4601/17/13/4780

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