Attention Deficit Hyperactivity Disorder

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopment disorder most known for either excessive activity or inattention, at levels that are otherwise not age-appropriate. It is estimated to affect 3-5% of children worldwide. People diagnosed with ADHD experience a range of symptoms depending on which of the following three subtypes they experience:

  • Predominantly inattentive (ADHD-PI or ADHD-I)
  • Predominantly hyperactive-impulsive (ADHD-PH or ADHD-HI)
  • Combined type (ADHD-C)

People with ADHD of any age are likely to have trouble with social skills, social rejection, language processing, anger management, or delays in speech, language, or motor development.

Approximately two-thirds of children have comorbidities including Autism Spectrum Disorder, learning disabilities, Oppositional Defiant Disorder, Conduct Disorder, anxiety, and mood disorders including depression. Sleep disorders are commonly found in people with ADHD.

Some non-psychiatric conditions such as Seizure Disorders may also be comorbid with ADHD.

People with ADHD may experience difficulty with executive functions such as attentional control, inhibitory control, and working memory. This may contribute to problems staying organized, time keeping, procrastination, paying attention and maintaining concentration, regulating emotions, and remembering details.

Time Blindness

One common symptom (or comorbidity, I’ve seen it referred to as both) of ADHD is time blindness, or the inability to sense time passing. People with time blindness (possibly also called chronoagnosia) lose track of time easily and can’t keep deadlines.

Design considerations

When we design for people with ADHD, we need to provide:

  • Neat and uncluttered layouts.
  • Soothing colors free of decorations and distractions.
  • A high-reinforcement environment that rewards good behavior and completion of tasks using positive language.
  • Clear and consistent organization.
  • Content that distinguishes important information, and groups related information into panels.
  • Large print and a clear font.
  • Easy-to-scan designs such as “zebra tables“, where the background color of data tables are alternated.
  • Wayfinding markers that let a person clearly know where they are in the content.
  • Brief and clear instructions.
  • The ability to leave and come back to a task without losing progress.
  • Make it easy to print or save appointment times, locations, and similar information.
  • Provide access to a map or GPS when providing instructions to reach a location.

In some situations where we’re designing an application to be immersive, offering the option to remind people when a set amount of time has passed may help them combat time blindness. Notifications and reminders that can be “snoozed” to pop up again when the user isn’t occupied with their current task may also help.

We need to avoid:

  • Animation, sound, or other distractions that can draw the person away from the task at hand.
  • Creating large blocks of text.
  • Vague or unpredictable buttons or links (“click here”).
  • Building complex and cluttered layouts.

Additional resources

On time blindness

These links don’t necessarily impact accessibility, but may be of interest if you’re unfamiliar with ADHD.