ADHD iceberg

You may know about the core symptoms of ADHD or recognize the key signs of this common disorder. But those are just the visible challenges. Many signs and symptoms lie below the surface and often aren’t recognized as being part of ADHD. 

ADHD is a neurodevelopmental disorder. That means it’s caused by differences in how the brain develops and functions. The three main symptoms of ADHD are inattention, impulsivity, and hyperactivity. 

But there are other less visible symptoms that people often don’t know about. These symptoms may also not be accurately captured in the manual that professionals use to diagnose ADHD.

The ADHD iceberg analogy helps people understand these below-the-surface symptoms. ADHD expert Russell Barkley popularized this model, and ADHD advocate Chris A. Zeigler Dendy created the original iceberg illustration.¹

Download the iceberg graphic  

You can use this picture to understand and talk to others about ADHD challenges.

Visible (external) symptoms

ADHD is complex, and it doesn’t look the same in everyone. First, it’s a spectrum disorder, meaning symptoms vary in amount and degree. Symptoms also often show up differently in girls and women than in boys and men. The iceberg goes a long way in explaining the many ways ADHD can affect people of all ages.

ADHD is a problem with executive function, which covers a wide range of skills. There are many versions of the iceberg, and they don’t all highlight the same invisible challenges. There’s some variation in which executive challenges they include.

Many people are familiar with the visible signs of ADHD, which are the key symptoms of the condition. These behaviors appear at the top of the iceberg since they’re more obvious. The three main symptoms:²

Inattention: Trouble paying attention and focusing. Visible signs include “zoning out” during conversations, daydreaming, or being easily distracted.

Hyperactivity: Being overly active. Visible signs include constant movement — fidgeting, walking around, tapping feet — and nonstop talking. (In adults it may look or feel like restlessness.)

Impulsivity: Trouble with self-control. Visible signs include interrupting others, grabbing for items without asking, and acting without thinking about consequences.

Most people with ADHD only have one or two of these symptoms. It’s less common to have all three. 

Invisible (internal) symptoms

The illustration shows the invisible signs of ADHD below the water’s surface, where most of the iceberg is. These are the challenges that aren’t always obvious or known to be part of ADHD. Common ones include:

Hyperfocus: When tasks or activities are interesting and rewarding, people with ADHD may be able to focus on them for long periods of time. But they may also have trouble shifting their attention to something else.

Trouble with time management: This might look like underestimating the amount of time it takes to complete certain tasks, difficulty multitasking, and forgetting to budget enough time for activities (time blindness).

Difficulty maintaining relationships: It can be hard to communicate and follow up with others, even loved ones. Constantly losing track of time and running late, or missing dates entirely, can put a strain on relationships and friendships.

Poor sleep: Sleep problems are common with ADHD. People often don’t get enough sleep or restful sleep. Reasons include not being able to wind down, procrastinating at bedtime, anxiety, and sleep disorders that co-occur with ADHD.³

Mood swings: People of all ages can have a hard time regulating their emotions. Up to two-thirds of adults with ADHD struggle with this form of self-control.⁴ Kids and adults may feel emotions more strongly and for longer than others. They may easily become frustrated, upset, or extremely excited. Kids and adults with ADHD can be moodier and more irritable than others.

Sensory issues: Sensory processing challenges often co-occur with ADHD.⁵ People with ADHD may be highly sensitive to tastes, noise, lights, and touch. They may also feel overwhelmed in crowded spaces. Sensory overload can sometimes trigger a stress response. For example, kids might have meltdowns. Adults might need to leave an overwhelming situation.

Trouble with working memory and executive function: ADHD is a problem with a group of skills known as executive function. Working memory is one of those skills, along with attention, self-control, organization, managing multi-step activities, completing tasks, and others. 

Anxiety: This mental health problem is common in both kids and adults with ADHD. Research shows that almost half of adults with ADHD also have an anxiety disorder.⁶ Not only do these two disorders often co-occur, they share some signs, too. These include restlessness, sleep issues, and low self-esteem. The overlap can sometimes make it hard to get an accurate diagnosis.

Low self-esteem: Many people with ADHD feel like they can’t meet expectations (including their own) no matter how hard they try. But these expectations don’t always consider the needs of people with ADHD.

ADHD symptoms from childhood to adulthood

Typically, ADHD first becomes noticeable in childhood. In most cases, symptoms continue into adulthood. But the signs of ADHD in adults often don’t look the same as ADHD symptoms in kids. Symptoms typically change as the brain continues to develop. 

Take hyperactivity. The signs may be very obvious in kids, who move and talk nonstop. As kids get older, this ADHD symptom can lessen or go away entirely. 

If people still have it as adults, they may not show any visible signs. But they might have feelings of restlessness, overly active thoughts, and quickly shifting internal focus.

With inattention, signs may exist early on in childhood. But the behavior might not appear out of the norm in very young children. Being daydreamy, forgetful, or easily distracted may not be obvious until later on, as school and other demands increase.

Impulsivity often continues beyond childhood, and it can lead to bigger problems as kids get older. For example, teens with ADHD are more likely to engage in risky behaviors, like substance use and unsafe sexual activity.² 

Teens may also jump from hobby to hobby and rapidly move from one dating situation to another. They might frequently change jobs, going from ones they find boring to ones that are novel or more interesting.

As adults, some people may find that their symptoms are more muted or more limited. That often depends on how they accommodate their differences and the type of jobs and activities they choose.

Using the ADHD iceberg for awareness and support

The ADHD iceberg has been around since 1998, and it’s been a popular resource. Both the analogy and the illustration make it easier to understand ADHD and explain the challenges to others. 

You can use it to talk to others who can provide more information and support, like teachers, health care professionals, and employers. If you’re a parent, you can share it with your child or with other family members.

Knowing the invisible signs and symptoms can help you better support the people in your life with ADHD. If you have ADHD, the iceberg can increase your self-awareness and let you know that the difficulties you’re having are part of your ADHD. You can also use it to raise awareness in your community or workplace.

Summary

ADHD is a common condition that’s caused by differences in how the brain develops. Many people know about the main symptoms, which can be very visible. These include inattention, impulsivity, and hyperactivity. 

Other ADHD signs and symptoms are “invisible” but just as challenging. People often don’t know about them or their connection to ADHD. These symptoms include trouble managing time, disorganization, mood swings, difficulty with relationships, and anxiety.

The ADHD iceberg shows the complex layers of the condition. The visible symptoms are labeled at the top of the iceberg. The invisible ones are labeled beneath the surface, where the bulk of the iceberg is.

The iceberg gives a good idea of the types of challenges that aren’t obvious but are still a part of ADHD. And the information can help you talk to others about supports, strategies, and treatments.