ADHD Glossary

(Nearly) All the terms you need to know when it comes to ADHD.

Attention-Deficit/Hyperactivity Disorder. You can find out more about what ADHD is here
Attention Deficit Disorder. This term is now considered outdated and all attention deficit symptoms fit under the umbrella of ADHD.
ADHD is split into three main subtypes:
Combined Type
Combined type (ADHD-C) - A subtype of ADHD characterised by both inattentive and hyperactive-impulsive symptoms of ADHD
Hyperactive-Impulsive Type
Hyperactive-Impulsive type (ADHD PH-I) - A subtype of ADHD characterised by impulsivity and hyperactivity, but lacking the symptoms of inattention
Inattentive Type
ADHD Inattentive type (ADHD-PI) - A subtype of ADHD characterised by inattentive symptoms, but lacking hyperactivity and impulsivity symptoms
Executive Function
This is a set of mental skills that include working memory, flexible thinking, and self-control. We use these skills every day to learn, work, and manage daily life.
ADHD is associated with deficits in executive function compared to those without ADHD.
Rejection Sensitivity Disorder (RSD)
People with ADHD can often be more sensitive to feelings of rejection due to deficits in emotional regulation.
RSD is not a medical diagnosis, but instead is a term used to describe those symptoms associated with ADHD.
Auditory processing disorder (APD)
APD is where you have difficulty understanding sounds, including spoken words.
People with APD find it difficult to speak and listen in noisy places, as well as understanding people who speak fast.
Hyperfocus is when a person with ADHD becomes “zoned in” on one particular topic for an extended period of time; usually something that they are interested in.
Hyperfocus can be towards things, but can also be towards people.

This refers to self-stimulating behaviours, usually involving repetitive movements or sounds.
It is mostly associated with autism, but stimming is also common in people with ADHD
ASD - Autism spectrum disorder. This is a developmental disability that can cause significant social, communication and behavioural challenges, it is often co-morbid with ADHD.
This is the presence of one or more additional conditions often co-occurring with a primary condition.
Common co-morbidities include ASD, anxiety, depression, bi-polar disorders.
Sensory Processing Disorder (SPD)
SPD is a condition in which the brain and nervous system are unable to correctly receive, organise and process information coming in from the senses, causing learning and behavioural problems.
Neurodiverse /Neurodivergent
This is the term for when someone's brain processes, learns, and/or behaves differently from what is considered "typical”, or “Neurotypical”. It includes conditions such as ASD and ADHD, as well as a number of others.
Dopamine is a chemical in the brain that controls how we feel pleasure.
For most people, doing work and accomplishing tasks causes a release of dopamine, which helps people to initiate, carry out, and complete these tasks.
Dopamine does not work the same way in people with ADHD, and is released primarily when interacting with something that the individual has an active interest in.
Masking is the process in which people change their behaviours to conform to the expectations of society.
For people with ADHD and ASD, this can involve actively suppressing their symptoms to “fit in” or “seem normal”.
Overstimulation/Sensory Overload
Overstimulation, a type of sensory processing difficulty, occurs when your senses relay more stimuli to the brain than it can handle. Rather than taking one thing in at a time, your brain can’t prioritise. Some people refer to this as getting “stuck.”
When your brain is stuck, it can start sending out signals that you need to escape your situation.