ADHD and how it’s been treated has evolved throughout history. It wasn’t until 1980 that “ADD,” or attention deficit disorder, was introduced by psychiatrists and psychologists in the DSM-III, the manual of diagnosis. In 1987, ADHD became the official, updated diagnosis and in 1994, the diagnoses that are used today were made standard. 

For more on the historical roots of ADHD as a diagnosis, feel free to check out “The History of ADHD”.

It might be surprising to learn that ADHD, despite having many different treatment options, does not have one singular root cause. Basically, depending on who you ask or what theory is most reflective of your (or a doctor or clinician’s) experiences or opinions, you might get a different answer to the question, “What causes ADHD?” or “Why do some people have ADHD?” 

In this blog, we’ll discuss the major different theories and how each theory would answer the question of, “What causes ADHD?” 

The Neurodevelopmental Theory of ADHD

The neurodevelopmental theory of ADHD posits that people with ADHD have different cognitive functioning–basically, their brains work differently than neurotypical people’s (or people without ADHD). This theory looks at differences in the brain and nervous system. For example, imaging studies of the brain show that there might be differences in how some parts of the brain are developed, including that parts of the brain might mature later for folks with ADHD. 

Using the neurodevelopmental theory of ADHD, theorists consider what reasons there might be for one’s brain to develop differently. This can include things like genetics, experiences of a parent or baby prior to birth, or postnatal (after birth) experiences such as a traumatic brain injury or being born premature. While the neurodevelopmental theory of ADHD has a definitive idea of how ADHD exists–as clear, visible differences in brain functioning and the brain itself–it doesn’t identify one specific cause. However, the neurodevelopmental theory does consider most of the factors that link to ADHD to influence one’s nervous system, brain, and biology. 

Connected to this are a few different perspectives on how ADHD exists in genes and what people inherit or pass down to offspring.

Genetic Component and Theory

Genetics, or genes, are the parts of our DNA that impact many parts of our lives. With ADHD, genetic components may play a large role. For example, some research done by the National Human Genome Research Institute identified a specific gene, Latrophilin 3 (LPHN3) that, in certain forms, could trigger ADHD. 

Heritability, or how likely something is to be inherited, is also an important factor as some research shows that ADHD is 74% likely to be inherited genetically. This means that if your child, sibling, parent, or other blood relative has ADHD, your chances of having ADHD might be rather high. That being said, not everyone who has a family member with ADHD also has ADHD, and this is because exactly how genes express themselves is not the same in every single person. 

Environmental Factors

Environmental factors can impact one’s mental functioning. For example, some research shows a link between an ADHD diagnosis and the diagnosed person experiencing trauma. 

Adverse experiences, such as experiencing or witnessing violence, losing a parent or loved one, serious illness, and other similar things can all be traumatic experiences.

Want to know more about the link between trauma and ADHD? Explore our blog about the similarities between trauma and ADHD here. 

The Social Model of Disability versus the Medical Model

The “medical model” is basically the model of how hospitals and medical doctors treat illness—something is generally deemed “wrong” and then it is treated until it is deemed better or cured.

For example, if a person has a headache, a doctor might recommend medication. There is less of a question around why the person might have gotten the headache in the first place—perhaps they can’t afford enough food, so they can’t eat regularly, and they get headaches when their blood sugar gets low.

The medical model encourages people to think of any kind of diagnosis like a problem to be solved, instead of information about themselves or their experiences. 

While not all people with ADHD consider themselves to have a disability, we can learn a lot by exploring the social model of disability and how it can be applied to people who are neurodivergent. The social model of disability looks not at the individual with the headache but at society. The social model asks, “What is it about society that needs to change to accommodate the way this person functions?”

In simpler terms, the medical model often tries to do things to help a person adapt to society and the world around them. The social model of disability explores how the world can be adapted to be more supportive, and less hostile, to individuals. 

Conclusion

All of these theories are different ways to think about ADHD and how it impacts people or how it might show up in your life if you’re wondering if you have ADHD. Regardless of what resonates with you, the best next step if you feel symptoms of ADHD are impacting you is to schedule a consultation for ADHD. An ADHD consultation with Self Made Psychology involves talking with clinicians with real, lived experience of ADHD and neurodivergence who will help you with compassion, care, and expertise. Reach out now to take your next step.