This glossary defines twenty terms that the neurodivergent community uses to describe shared experiences of ADHD, autism, and related neurotypes. Each entry explains what the term means, where it came from, why it matters, and what research backs it. The neurodivergent movement, founded by sociologist Judy Singer in 1998, reframed autism and ADHD as natural variations in neurology rather than deficits. Since then, community-generated language has expanded to describe experiences that mainstream psychiatry had no words for. This glossary collects the terms you are most likely to encounter in support groups, therapy, memoirs, and TikTok. Understanding this vocabulary matters because neurodivergent people often spend decades feeling wrong before discovering that their experience has a name, a community, and sometimes research. Russell Barkley's work on ADHD executive function, Tony Attwood's research on autism, William Dodson's naming of rejection sensitive dysphoria, and Christine Miserandino's spoon theory are all key sources. The community voice matters: many terms here were coined by neurodivergent people themselves, not clinicians. Masking was first described by autistic women (Liane Holliday Willey, Sarah Hendrickx) before academic researchers like Laura Hull at UCL measured it. Use this glossary whether you are newly diagnosed, self-identified, exploring, a loved one, or a clinician trying to speak your client's language.

1. What Is Masking?

Masking is the effort neurodivergent people (especially autistic women) make to hide their traits and pass as neurotypical: rehearsing small talk, suppressing stims, forcing eye contact. Laura Hull at UCL developed the CAT-Q to measure it. Chronic masking correlates with exhaustion, anxiety, depression, and delayed diagnosis. It matters because masking often hides the person from themselves. Citation: Hull et al., Journal of Autism and Developmental Disorders (2019).

2. What Is Stimming?

Stimming (self-stimulatory behavior) is repetitive movement or sound that regulates the nervous system: rocking, flapping, tapping, humming, chewing. It is common in autism and ADHD. Research by Kapp et al. (2019) showed that stimming is helpful self-regulation and suppressing it increases distress. The neurodiversity movement advocates for the right to stim. Citation: Kapp et al., Autism (2019).

3. What Is Executive Dysfunction?

Executive dysfunction is difficulty with the brain's management system: planning, initiating, organizing, switching tasks, working memory. Russell Barkley at the University of Massachusetts Medical School frames ADHD as a disorder of executive function. It affects autism too. It matters because it explains why smart people cannot do simple tasks. Citation: Barkley, Executive Functions (2012).

4. What Is Rejection Sensitive Dysphoria?

Rejection Sensitive Dysphoria (RSD) was named by psychiatrist William Dodson to describe the extreme emotional pain ADHD adults feel at perceived rejection or criticism. It is not a formal diagnosis but a widely recognized clinical experience. Brain research suggests deficient emotional regulation circuits. It matters because it explains why small slights feel catastrophic. Citation: Dodson, ADDitude Magazine (2017).

5. What Is Hyperfocus?

Hyperfocus is the intense, absorbed concentration on a task that feels interesting or urgent, common in ADHD and autism. It is the opposite of the distraction stereotype. Hupfeld et al. (2019) studied it empirically and found it can be productive or pathological. Hours vanish. It matters because ADHD is not an attention deficit but a regulation deficit. Citation: Hupfeld, Abagis and Shah, ADHD Attention Deficit and Hyperactivity Disorders (2019).

6. What Is Time Blindness?

Time blindness is the ADHD-linked difficulty perceiving the passage of time, estimating how long tasks will take, or remembering future events with appropriate urgency. Barkley describes ADHD as temporal myopia. It matters because it explains chronic lateness, missed deadlines, and the now-versus-not-now split that ADHDers live in.

7. What Is the Autism Spectrum?

The autism spectrum refers to the range of presentations and support needs of autistic people, from those who need daily assistance to those who hold PhDs. DSM-5 (2013) consolidated previous categories (Asperger's, PDD-NOS) into Autism Spectrum Disorder. Lorna Wing's triad of impairments (1979) preceded the modern concept. The spectrum is not linear, and community activists prefer wheel metaphors.

8. What Is AuDHD?

AuDHD is the community term for people who are both autistic and ADHD. The comorbidity is extremely high (30 to 80 percent depending on study). DSM-5 allows dual diagnosis since 2013. The experience combines seemingly opposite traits (need for routine plus novelty seeking). It matters because AuDHDers often feel contradictory and misunderstood. Citation: Rommelse et al., European Child and Adolescent Psychiatry (2010).

9. What Is Neurodivergent Burnout?

Neurodivergent burnout (especially autistic burnout) is the prolonged exhaustion and functional decline that follows chronic masking and sensory overload. Dora Raymaker at the Autistic Adults Research Consortium led the first qualitative studies in 2020. It differs from depression and ordinary burnout. It matters because recovery requires unmasking, not just rest. Citation: Raymaker et al., Autism in Adulthood (2020).

10. What Is Spoon Theory?

Spoon theory was coined by Christine Miserandino in a 2003 essay explaining lupus fatigue to a friend using spoons as units of energy. It was adopted by chronic illness and neurodivergent communities. Each daily task costs spoons; running out means shutdown. It matters because it gave chronically tired people a shared vocabulary with healthy friends. Citation: Miserandino, ButYouDontLookSick.com (2003).

11. What Is Sensory Overload?

Sensory overload is the state in which the nervous system cannot process incoming stimuli, common in autism and sensory processing disorder. It causes meltdowns, shutdowns, or escape behavior. A. Jean Ayres pioneered sensory integration research in the 1970s. It matters because environments most people find fine can be torture for others. Citation: Ayres, Sensory Integration and the Child (1979).

12. What Is Info Dumping?

Info dumping is the autistic and ADHD joy of sharing detailed knowledge about a special interest, often at length and without checking listener engagement. The community reframes it as a love language rather than a social failure. It matters because autistic people often show affection through sharing what they love.

13. What Is a Special Interest?

A special interest (SpIn) is the deeply absorbing focused passion common in autism, often lifelong, often encyclopedic. Research by Winter-Messiers (2007) showed special interests are linked to mental health and skill development. They are not obsessions to be cured. Citation: Winter-Messiers, Remedial and Special Education (2007).

14. What Is Alexithymia?

Alexithymia is difficulty identifying and describing your own emotions. It was named by Peter Sifneos in 1973. About 50 percent of autistic people have it, compared to 10 percent of the general population (Kinnaird et al. 2019 meta-analysis). It matters because it explains why feelings can be strong and unnameable at the same time. Citation: Kinnaird et al., European Psychiatry (2019).

15. What Is Pathological Demand Avoidance?

Pathological Demand Avoidance (PDA), now often called Persistent Drive for Autonomy, was identified by Elizabeth Newson in the 1980s as an autism subtype where the person experiences demands as unbearable. It is recognized in the UK but not the DSM. It matters because ordinary parenting and teaching strategies backfire. Citation: Newson et al., Archives of Disease in Childhood (2003).

16. What Is Scripting?

Scripting is using memorized phrases or pre-planned sentences to navigate social situations. It is common in autism. It can be functional (getting through phone calls) or echolalic (repeating favorite dialogue). It matters because scripting is effort, not laziness.

17. What Is Echolalia?

Echolalia is the repetition of words, phrases, or sounds, either immediately or delayed. Once thought meaningless, Barry Prizant's work showed it is communicative. Delayed echolalia (quoting movies or songs) is often functional expression. It matters because stopping echolalia removes a communication tool. Citation: Prizant, Uniquely Human (2015).

18. Why Do Autistic People Avoid Eye Contact?

Many autistic people avoid eye contact because it feels physically overwhelming, overstimulating, or cognitively costly. Hadjikhani et al. (2017) showed eye contact activates the autistic amygdala more strongly than in neurotypicals. Forcing eye contact can impair processing and communication. Citation: Hadjikhani et al., Scientific Reports (2017).

19. What Is Body Doubling?

Body doubling is the ADHD strategy of having another person present (in person or video) while you do a difficult task. Their mere presence provides accountability and reduces executive dysfunction. Services like Focusmate emerged around this. It matters because it makes impossible tasks possible.

20. What Is Pattern Recognition as an Autistic Strength?

Many autistic people excel at pattern recognition in data, systems, language, or music. Laurent Mottron's enhanced perceptual functioning model (2006) proposes this is a fundamental autistic cognitive style. It reframes autism as cognitive difference rather than deficit. Citation: Mottron et al., Journal of Autism and Developmental Disorders (2006).