What is ADHD?

Attention-deficit/hyperactivity disorder (ADHD) is classified as a neurobehavioral, genetic disorder of self-regulation. It is a neurobiological brain disorder resulting in reduced dopamine availability, involving both chemical and structural differences. 

Historically, ADHD has been characterized by developmentally inappropriate levels of inattention, impulsivity, and hyperactivity. 

Symptoms also include difficulties with:

  • attention regulation

  • impulse control

  • emotional control

  • executive functioning

The disorder was first described in 1902 by British pediatrician Sir George Frederic Still, who called it “an abnormal defect of moral control in children.”

(Meaning, even though these kids could be highly intelligent, they couldn't seem to control their own behavior the way typical children could.)

Previous clinical names for ADHD have included "brain injured," "clumsy child syndrome," and even "minimal brain dysfunction" — until psychologists settled on "Attention deficit disorder" in 1980 (DSM 3). It was later updated to include ADHD in 1987 (DSM 3R rev), and the terms ADD & ADHD were combined in 1994 (DSM 4) to include 3 subtypes: ADHD inattentive type, ADHD hyperactive-impulsive type, and ADHD combined type.

So, while you still may hear the term "ADD" used colloquially to refer to a non-hyperactive presentation, the terms hasn't been used in a clinical setting in nearly 30 years.

How common is ADHD?

Although it might seem like you're seeing ADHD mentioned everywhere right now, that's probably because you've started looking into it and the algorithms have started serving you more content related to ADHD. Most experts estimate that roughly 5% of the word's adult population has ADHD.

What is neurodivergence?

The term "neurodivergent" was first coined in 1998 by Australian sociologist Judy Singer to recognize that everyone's brain develops in a unique way. You'll see the terms "neurodivergence" or "neurodiversity" a lot in discussions of ADHD because a) it's used in relation to "neurotypical" brains (ie. the majority of thinkers); and b) ADHD tends to co-occur with many other neurobehavioral conditions.

Neurodivergence is an umbrella term that includes many differences in cognition or neurology (basically, brains that don't work in a "typical" way).

Under this umbrella:

  • ADHD and ADD

  • Autism

  • Dyslexia

  • Dyspraxia

  • Dyscalculia

  • Schizophrenia

  • and more

While each of those conditions has its own symptoms and treatments, they're similar in that our brains work differently.

Here's a short article with more detail and sources if you're curious.

What about those other conditions?

Many experts have found that ADHD and autism have large crossover areas. You might wonder if you have autism as well as ADHD, or maybe some of the other conditions under the neurodivergent umbrella.

I wondered that myself after my ADHD diagnosis. If you think you might have one of those other conditions, I'd recommend going through the same exploratory process for those as we're doing here for ADHD.

And ultimately, why I don't cover those other than this quick nod to them: I want to be respectful of the experts in those fields, and stay in my lane speaking only from my own experience as a woman diagnosed with ADHD.