ADHD & Neurodiversity Dictionary

ADHD Summary

A growing, plain-language dictionary of ADHD and neurodiversity terms, grouped by theme so you can find what you need without reading the whole page. Each entry links to a deeper article. This page gives you the short version.

Key facts

• Every definition written for late-diagnosed women, not clinicians
• Terms grouped by theme so you can find what you need without reading the whole page
• Each term links to the article where it is explored in depth

What this means for you: Bookmark this page. Come back whenever you hit a term that does not make sense. If you want to see where ADHD is showing up in your life right now, take the ADHD Wheel of Life →

What is ADHD?

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental condition affecting how the brain regulates attention, impulse control, and executive function. It is not a deficit of attention but a difference in how attention is allocated, often leading to difficulties with focus, organisation, emotional regulation, and time management.

ADHD has three presentations: predominantly inattentive (the one most commonly missed in women), predominantly hyperactive-impulsive, and combined. It affects approximately 3-4% of adults and is a lifelong condition.

What are neurodivergent and neurotypical?

Neurodivergent describes a brain that functions differently from the statistical majority, including people with ADHD, autism, dyslexia, dyspraxia, and other neurological differences. Neurotypical describes a brain that functions within the range considered typical. These are descriptive terms, not value judgments.

The language matters because it shifts the frame from “what is wrong with you?” to “how does your brain work differently?” Many of the difficulties ADHD causes come from living in systems designed for neurotypical brains.

What is late diagnosis?

Late diagnosis refers to receiving an ADHD diagnosis in adulthood, typically after years or even decades of living without knowing why you felt different. For women, late diagnosis is the norm rather than the exception, because the diagnostic criteria were built around hyperactive boys, and the presentation most common in girls and women was systematically missed.

Late diagnosis brings relief and grief in equal measure: relief that there is an explanation, and grief for the years spent blaming yourself for something that was never your fault. The specific shapes this takes are explored in why so many women doubt their ADHD diagnosis after assessment.

What is executive function?

Executive function is the set of mental processes that help you plan, organise, start tasks, manage time, hold information in working memory, and regulate your behaviour. In ADHD, executive function is inconsistently available, not absent, meaning you can do these things brilliantly sometimes and not at all other times.

The inconsistency is the cruelest part. Because you can sometimes pull off extraordinary feats of planning, the world assumes you are choosing not to bother the rest of the time. You are not choosing. This is one of the reasons so many women doubt their ADHD diagnosis after assessment.

What is working memory?

Working memory is the ability to hold and manipulate information in your mind over short periods. In ADHD, working memory capacity is typically reduced, affecting everything from following conversations to remembering what you walked into a room for.

For imposter syndrome, working memory is the silent accomplice. It does not reliably store evidence of your successes, but it holds onto evidence of your failures with forensic precision. The role it plays in the fraud feeling is explored in why you feel like a fraud.

What is hyperfocus?

Hyperfocus is the ADHD ability to become intensely absorbed in a task or interest to the exclusion of everything else. It is not a superpower you can summon on demand. It is an attention regulation difference that works brilliantly when it aligns with what needs doing and causes real problems when it does not.

You cannot choose to hyperfocus on the tax return instead of the Wikipedia rabbit hole. The mechanism is the same one that makes it hard to switch tasks or notice three hours have passed.

What is emotional dysregulation?

Emotional dysregulation is the difficulty managing the intensity and duration of emotional responses. In ADHD, emotions arrive faster, hit harder, and take longer to settle than they do for neurotypical people. It is not being “too sensitive.” It is a neurological difference in how the brain processes emotion.

Many women are diagnosed with anxiety or depression for years before anyone considers that the emotional intensity is ADHD-driven. The feelings are real. The volume they arrive at is the ADHD part.

What is achievement amnesia?

Achievement amnesia is the ADHD pattern of forgetting or discounting past successes while vividly retaining every failure. It happens because working memory does not store evidence of competence the way it stores evidence of mistakes, leaving you perpetually starting from zero.

You did something brilliant last month. You cannot remember what it was. But you can describe in detail the email you sent with a typo three years ago. How this feeds the fraud feeling in ADHD is worth understanding.

What is imposter syndrome?

Imposter syndrome is the persistent feeling that your achievements are unearned and that you will eventually be exposed as a fraud. For women with ADHD, it is amplified by masking, rejection sensitive dysphoria, working memory gaps, and years of undiagnosed self-blame.

The ADHD version starts earlier and runs deeper than the corporate version. It is not “they will find me out.” It is “they already did. I just got away with it for longer than I should have.” The full picture is in ADHD and imposter syndrome: why you feel like a fraud.

What is rejection sensitive dysphoria (RSD)?

Rejection sensitive dysphoria (RSD) is an intense, near-instant emotional response to perceived criticism, rejection, or falling short. Research estimates that around 99% of adults with ADHD experience RSD, and for roughly one in three it is the single most impairing ADHD trait.

RSD is what turns a small piece of feedback at 2pm into a month of positive comments being genuinely obliterated by 3pm. The response is not proportional to the event. How it amplifies imposter syndrome in ADHD is one of the least understood mechanisms.

What is masking?

Masking is the learned suppression of ADHD traits to meet neurotypical expectations. For late-diagnosed women, it often starts in childhood as survival, becomes automatic by adulthood, and quietly generates imposter syndrome because if the version of you that people respond to is not really you, their approval can never land.

Research shows that 83% of adults with ADHD and/or autism score high for masking in work or school contexts, compared with just 21% around people who share their diagnosis. The connection between masking and the fraud feeling is explored in how masking and imposter syndrome feed each other.

What is social camouflaging?

Social camouflaging is the deliberate or automatic use of strategies to hide neurodivergent traits in social situations. It overlaps with masking but specifically describes the social performance: monitoring facial expressions, scripting conversations, suppressing stims, and copying neurotypical behaviour.

Research has identified social camouflaging as the mediating variable between ADHD symptoms and imposter feelings. Higher social camouflaging in women with ADHD correlates with lower life satisfaction and higher depressive symptoms. The research behind this is unpacked in ADHD masking and the exhaustion of seeming fine.

What is internalised stigma?

Internalised stigma is the process of absorbing negative beliefs about your own condition and turning them into self-judgment. For late-diagnosed ADHD women, it typically sounds like “I am lazy,” “I am stupid,” or “everyone else manages, so what is wrong with me?”

Internalised stigma does not disappear with diagnosis. In fact, it often gets louder, because the diagnosis gives the inner critic new material. It is one of the key drivers of post-diagnosis doubt.

What is post-diagnosis doubt?

Post-diagnosis doubt is the surprisingly common experience of questioning whether you really have ADHD after a formal diagnosis. It is driven by RSD, internalised stigma, decades of being told “you are not trying hard enough,” and the fraud feeling itself looking for new ground to stand on.

The voice returns within weeks: maybe the assessor got it wrong, maybe I was exaggerating. This is not evidence your diagnosis is wrong. It is evidence of how deeply the fraud feeling is wired in. Why this happens and what actually quietens the doubt is worth reading.

“I’d been on the NHS waiting list for years. The assessment was thorough. The answer was clear. And my first thought was: maybe it’s not ADHD. Maybe I’m just making excuses for myself.”
— Nishia Wadhwani

What is stimulant medication?

Stimulant medications are the most commonly prescribed and most effective pharmacological treatment for ADHD. They work by increasing dopamine and/or norepinephrine in the brain. The two main types in the UK are methylphenidate and lisdexamfetamine.

The name “stimulant” is misleading. For ADHD brains, these medications provide the dopamine the brain is not producing efficiently, which typically results in feeling calmer, more focused, and better able to start and finish tasks. How supply chain disruptions can affect your ADHD medication availability is worth knowing.

What is methylphenidate?

Methylphenidate is the most commonly prescribed stimulant medication for ADHD worldwide. It works by increasing dopamine and norepinephrine availability in the brain. UK brand names include Concerta, Ritalin, Equasym, Medikinet, and Xaggitin.

It comes in immediate-release and modified-release formulations. The right formulation and dose varies between individuals and often requires a titration period.

What is lisdexamfetamine (Elvanse)?

Lisdexamfetamine is a long-acting stimulant medication prescribed for ADHD, sold under the brand name Elvanse in the UK (Vyvanse in the US). It is a prodrug, meaning it is inactive until the body converts it, giving a smoother onset and longer duration than some other stimulants.

It is one of the most commonly prescribed ADHD medications in the UK and a controlled substance requiring regular prescriber review.

What is non-stimulant medication?

Non-stimulant ADHD medications work differently from stimulants, typically by affecting norepinephrine rather than dopamine. They are prescribed when stimulants are unsuitable or cause unacceptable side effects. The main non-stimulant in the UK is atomoxetine.

Non-stimulants generally take several weeks to reach full effect and are taken daily. They are not controlled substances, which simplifies prescribing.

What is atomoxetine?

Atomoxetine is a non-stimulant ADHD medication that works by increasing norepinephrine levels in the brain. It is typically prescribed when stimulant medications are unsuitable, ineffective, or when there are concerns about side effects. Brand name: Strattera.

Unlike stimulants, atomoxetine takes several weeks to reach full effect. Available on NHS prescription.

What is perimenopause?

Perimenopause is the transitional phase before menopause when oestrogen levels fluctuate and decline. For women with ADHD, perimenopause often amplifies existing symptoms dramatically because oestrogen plays a direct role in dopamine regulation. Many women are first diagnosed with ADHD during perimenopause, when falling oestrogen strips away the coping strategies that kept them functioning.

Research shows 54.2% of women with ADHD experience debilitating perimenopausal symptoms, peaking at ages 35-39. HRT can help stabilise both perimenopausal and ADHD symptoms for some women, but this is a conversation for your GP. The role perimenopause plays in unmasking ADHD in midlife is explored further.

What is Right to Choose?

Right to Choose is an NHS England policy that allows patients to choose their healthcare provider for a first outpatient appointment, including ADHD assessments. It means you can ask your GP to refer you to a provider with shorter waiting times at no cost to you. It does not apply in Scotland, Wales, or Northern Ireland.

Some Integrated Care Boards (ICBs) have placed restrictions on how it operates in their area. If your GP is unfamiliar with Right to Choose for ADHD, ADHD UK maintains an up-to-date guide. The full picture of ADHD waiting list statistics in England puts the scale of the problem into context.

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If you have read this far, you now have more language for your own experience than most people get in the first year after diagnosis. That matters. Not because the words fix anything, but because when you can name what is happening, you stop blaming yourself for it. Every term on this page is something you were never told about, never taught, and never given the chance to understand while it was shaping your life. Now you have it. Use it gently.