One thing I was super interested in learning more about was how medications, such as Adderall and Ritalin, help individuals with ADHD. When doing research for my final project for a summer course I took, I had the opportunity to read several research articles on the biological mechanisms behind these medications. Along the way I was also able to learn more about what biological deficits are involved in ADHD.
In this post, I will share with you some of my findings from this research. When researching, I found everything I read super interesting since I never knew what actually caused my ADHD. Hopefully, you all find this information as amusing as I did.
First, it's important to understand some basic terminology. A neurotransmitter, is a chemical substance, that act as "messengers" to other neurons and muscles. These "messages" give the receiving neuron/muscle instructions on what to do. Neurotransmitters are released at the synaptic cleft, which is the space that separates two neurons and helps send nerve impulses between neurons.
Individuals who have ADHD lack specific neurotransmitters:
Dopamine: Dopamine impacts one's movement, mood, motivation, and attention.
Norepinephrine: Norepinephrine can act as either a hormone or a neurotransmitter. When it functions as a stress hormone, it can affect one's attention.
Serotonin: Serotonin regulates an individual's mood, social behavior, sleep, and memory.
In terms of medication, all the information I found regards dopamine. Individuals with ADHD have overly efficient dopamine-removal systems. This means that dopamine is removed from the body before it even has time to act, and since dopamine impacts one's attention, a deficit of it could cause attention difficulties. There are three types of medication that I've researched:
Dextroamphetamine (Adderall): Dextroamphetamine is a stimulant medication that increases the synaptic activity of dopamine and norepinephrine. This increases the release of neurotransmitters in the synaptic cleft, which decreases the reuptake back into the presynaptic neuron (the neuron that fires neurotransmitters to the other neuron), and inhibiting the breakdown of these neurotransmitters. By preventing the breakdown of dopamine and norepinephrine, dextroamphetamine is giving these neurotransmitters more time to take action on an individual's nervous system, therefore, enhancing one's attention and motivation.
Methylphenidate (Ritalin): Methylphenidate is a stimulant medication that increases dopamine signaling through multiple actions, such as blocking the dopamine reuptake transporter and amplifying dopamine response duration. As a result, the time dopamine has to take its effect is elongated, giving the individual enhanced attention and motivation.
Atomoxetine (Straterra): Atomoxetine is one of the only non-stimulant medication for ADHD. It is a selective inhibitor of synaptic reuptake and, more specifically, it increases the extracellular levels of dopamine in the prefrontal cortex. Additionally, it boosts levels of norepinephrine. Since both dopamine and norepinephrine levels are increased, the individual's attention is enhanced as a result.
While researching this, I found it super interesting to learn more about what deficits I had in my brain and how the medication helps me better focus. Prior to this research, I barely knew anything about the biological mechanisms behind ADHD, and now that I had the opportunity to look into it, I'm so much more intrigued by the brain and how it works.
I know this post has a lot of scientific terms that are a little complicated for me to explain, but hopefully you get the basic gist: Individuals with ADHD have a fast acting dopamine-removal systems, and medication either helps inhibit these dopamine transporters (that are involved in the removal system) to give dopamine more time to act or increases the amount of dopamine in the body.
Hopefully, you all found this as interesting as I did. It's so fascinating to learn more about the brain!