The clock in the hospital meeting room had stopped. Silent, as if out of courtesy for its audience – a cognitive behavioural therapy (CBT) session for people with ADHD (Attention Deficit Hyperactivity Disorder) – one less distraction for those in attendance. Along the hallway, in the clinic’s waiting room, another timepiece ticked tormentingly onwards to its own assorted group of patients.
I was one of those in the CBT session, freshly diagnosed with ADHD at the age of 38 and our frozen clock had caught my elusive attention, like a big silent metaphor for my world standing still. To the outside world, my diagnosis is probably inconsequential. To me, it came with a bittersweet realisation that nature had crafted my brain differently to others – with consequences for how I saw my past, present and future. It’s fair to say the disorder has had a fairly crippling effect on various areas of my life.
The diagnosis has given me a better understanding and respect for the condition’s positive aspects, its limitations, and the coping strategies I’ve inadvertently created over the years to appear “normal”. It has given me the option of medication to partially control my condition, and it has helped me become more at peace with myself. In short, it has been a revelation to at least know what I’m dealing with.
Beyond these personal thoughts, one thing I have noticed since my ADHD diagnosis began is the recurring reference to something called “the normal brain”. Clinicians, fellow people with ADHD use the phrase and it appears across the internet. And so I wanted to know what “normal” means for a brain. Are there really stark divides that the use of this kind of term implies? Or are we all more similar than different?
I set to find out, and the more I researched, the more I discovered just what a complex and sometimes controversial question this is.

Any individual's traits will fall on a vast spectrum, with no clear dividing lines between what is "normal" and what is "abnormal" (Credit: Emmanuel Lafont)
According to one survey from 2016, around 62 million people across the globe were thought to have an autism spectrum disorder (including Asperger's syndrome), and 63 million had ADHD (though there can be crossover as some with autism can have ADHD and vice versa). That’s not to mention many other conditions – such as dyslexia, Tourette’s and Williams Syndrome (which involves a hypersocial personality) – that are also be due to differences in the brain’s anatomy.
People involved in the diagnosis and discussion of these conditions often use the term “neurodiverse” to describe the differences, and “neurotypical” to describe everyone else. But these terms have a long history and their meaning is constantly evolving.
The word neurodiverse was first coined in 1998 by an Australian sociologist, Judy Singer, who used it in her honours thesis. Shortly afterwards, it was picked up by a US journalist writing in a 1998 edition of The Atlantic, and the term began to evolve from there. As Singer explains to me, her original aim was to draw attention to a wide variety of conditions.

Journalist Howard Timberlake went on a quest to understand what we mean by a "normal" brain (Credit: Emmanuel Lafont)
“It was a time of incredible sharing and exploration,” she says. “I was just so overwhelmed with all these senses that people had that we didn't even know about – people who couldn’t recognise faces, people with extraordinary synaesthesia. There are so many things in the mind that we never imagined.
“I just thought, this is incredible diversity. With our stupid educational systems, we're trying to lock people into this narrow channel, instead of exploring what this diversity can bring us. We needed a movement, like the feminist movement, and that's where it came from.”
The term has since been employed for many purposes – as a word for empowerment, a means for celebrating qualities some neurological conditions can bring, and as a term of identity. But Singer had never intended for it to be used to describe a particular condition. Instead, she meant to for it to be used in a more general sense, to describe the variety of all brains.
“You cannot have neurodiverse as an adjective to describe anything else except the whole world,” she says. She draws a parallel with “biodiversity”, which is not used for a particular type of plant or animal but the overall variety of every living creature. “It’s the property of the whole biosphere.”

Neurodiversity was coined to describe the variety of human brains - in much the same way that biodiversity describes the variation of life on Earth (Credit: Emmanuel Lafont)
The term neurotypical began life around the same time as a means of describing those who do not display autistic or other atypical patterns of thoughts or behaviour. For medical purposes at least, this term is surely an acceptable way of describing people without any particular condition?
Well, not exactly… The developmental neurobiologist-turned-writer Mo Costandi suggests that it can come with its own negative associations. “These terms... were not coined by neuroscientists,” he says. “Neurotypical, is a term that was coined, I believe, by neurodiversity advocates to describe non-autistic people. And since then it has sort of crept into the scientific literature. Some autism researchers will use the term neurotypical in their studies, simply to describe a control group. But now, I'm strongly of the opinion that they [neurodiverse and neurotypical] are not valid terms, and they actually have very little use to us as neuroscientists.”
Many people with conditions like autism find that the term neurodiversity is a useful and positive way of self-defining their identity and their community
In his opinion, “the vast majority of neuroscientists will probably have never heard of these terms”.
Other experts are more positive about the terms. “I think that the term neurotypical is a good one and is an improvement over the term normal,” says Thomas Armstrong, author and executive director of the American Institute of Learning. “It doesn't necessarily define what is ideal, as an abstract concept, but it says this is what's typical.” That makes it preferable to something like “normal”, in his eyes.
Even so, Armstrong agrees that reality is far more subtle than these terms would suggest. “We typically see kids do X, Y, and Z. So, in terms of defining these kids, we can say neurotypical, but to tell you the truth, ultimately, I see that the more we learn about a child, the more they appear in their true diversity as a unique individual. And if we see each child, each teen, each adult as a unique individual, then all bets are off as far as creating a dividing line between those who are neuro-diverse and those who are neurotypical.”
Nature vs nurture
These may seem like academic disputes. Ultimately, many people with conditions like autism find that the term neurodiversity (and its contrast, neurotypical) is a useful and positive way of self-defining their identity and their community. There’s certainly a need to reduce the stigma.
As Armstrong argues, we should try to question our assumptions about different behaviours and the value judgements we place on them. He points out that when he is delivering lectures, some people with autism will walk around the room. Clearly, that is not the way that most of the stationary audience are behaving. “But why is it ‘abnormal’ to want to move and learn at the same time?”
After all, these norms are often the result of social convention. “We're set up with a culture in such a way that we have expectations for behaviour, we have constants, we have guidelines, we have morals – and all for good reason,” says Armstrong. “Society would fall apart without that. [But] I like to look back at the whole picture, and when I do that it makes the concept of normal very, very questionable, very muddy. And that's why I like to call people's attention to it, so that they don't automatically fall into unconscious or implicit biases.”

Our brains are as unique as our fingerprints (Credit: Emmanuel Lafont)
By recognising those biases, we can then change the environment to cater for people’s different needs. Some progress is being made – UK supermarket chain Morrisons have introduced a weekly “quiet hour”, for instance, for autistic shoppers who struggle with music and noise. A number of other big supermarket chains are now trialling similar initiatives.
Organisations such as the UK’s National Autistic Society also have guides for employers on making their company more accommodating to people with the condition. This is not just of benefit to individuals – people with autism often have many strengths that would be an asset for companies, if only those strengths were better recognised and allowed to flourish.
Neural fingerprints
Catherine Harmer, a cognitive neuroscientists at the University of Oxford, agrees that all brains are different. “We're all unique... kind of like a fingerprint,” she says.
“There's a huge diversity, and what might be functional in one context, might not be functional [in another]. In many cases, there's not one definition of abnormal, but there will always be people who require, through a combination of their genes, their environment, the situation that they're in, will be functionally impaired, will have challenges they need help with.”
She emphasises that we still need to understand the causes and consequences of these differences. “I would move away from the judgment of it being normal or abnormal, and think about if there’s an impediment that might be treatable,” she says.
It’s for this reason that we still need diagnostic labels, even if some fear that we are now "over-medicalising" the mind. As I have found myself, having a specific diagnosis can be incredibly helpful. Medical professionals and scientists need informed criteria to study the brain, the mind and identify those in need of help so they can suggest the best treatments.

Diagnoses are essential to ensure that people get the support they need - but there is a risk of "over-medicalising" traits and behaviours (Credit: Emmanuel Lafont)
It is also worth remembering that lots of people who do not meet the diagnostic criteria for ADHD may exhibit certain traits of the condition. How many of the people around you say “I'm always forgetting my car keys” or “I find it hard to concentrate sometimes” and “my memory for names is bad”? But that doesn't necessarily mean these people have ADHD. It's when those traits, combined with other symptoms, are so severe and constant that they have a significant impact on daily life.
To diagnose ADHD, like other disorders, a detailed diagnosis is required by a clinician. This involves looking at a person's life history, not to mention a thorough assessment of the individual’s symptoms and even asking loved ones for their own observations on the individual's behaviours. With that diagnosis, we can then be offered therapies like CBT and medication that could help us manage the difficulties that come with the conditions.
Ultimately, we all share some core systems, but beyond these our brains are as familiar yet as varied as the stars in the night sky
–When making those assessments, the evidence can be obvious, or can take some further sleuthing on the clinician’s part to determine who meets the criteria and who do not display enough evidence of irregularities to warrant a diagnosis. That area… you know, the one that’s diverse-yet-without-symptoms-of-a-specific-condition?
Ultimately, we all share some core systems, but beyond these our brains are as familiar yet as varied as the stars in the night sky. We can see the value of certain diagnostic labels while also acknowledging the fact that each of us has our own unique profile of traits, with strengths and weaknesses.
As Harmer suggests: “I think there's lots of differences between people when it comes to brains and the psychological systems and behaviour that the brain is in charge of. It is like saying what makes a normal face.”
Ten months into my own diagnosis, I now have some newly built foundations for understanding myself as I tackle the next phase of my life. Personally, I'm not hankering for a term to compare myself to others. With a greater perception of not just my limitations and quirks, but the advantages ADHD gives me, I am only thankful for the continued research into my condition. We all have a huge constellation of traits that – in their enormous variety as much as their similarities – help to define our species.
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What is ADHD?
Attention Deficit Hyperactivity Disorder is a neurodevelopmental disorder that can affect behaviour. The brain’s executive function system is, well, not functioning as expected. Key symptoms of ADHD are inattention, hyperactivity and impulsivity. It can also be hard to rest, regulate emotion or have a “working memory” (the ability to store information in your head in the short term). It's complex, commonly going hand in hand with anxiety, depression, dyslexia and dyspraxia, to name a few. It’s also one of the best-researched mental health conditions.
Diagnosis is thorough and carefully looks at whether symptoms have a significant impact on multiple areas of your life. Adults with ADHD will have had it since childhood, and not everyone with ADHD will experience the same balance between the key symptoms – for example your brain might be internally hyperactive, but you may not be outwardly restless. The attention deficit part can be confusing as a common feature of ADHD is only having two attention settings – random or “hyperfocus”, where it’s difficult to switch off from a task. On the flipside, people with the condition tend to be more creative, resilient, empathetic, energetic and much more.
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