Attention-deficit/hyperactivity disorder (ADHD) is one of the most common childhood neurodevelopmental disorders. Children with ADHD often have difficulty with inattention, hyperactivity and impulsivity. Kids usually receive a diagnosis during childhood, and the condition often lasts into adulthood. However, effective treatment is available.

What is ADHD?

Attention-deficit/hyperactivity disorder ADHD is one of the most common and most studied neurodevelopmental disorders in children. “Neuro” means nerves. Scientists have discovered there are differences in the brains, nerve networks and neurotransmitters of people with ADHD.

ADHD is a long-term (chronic) brain condition that causes executive dysfunction, which means it disrupts a person’s ability to manage their own emotions, thoughts and actions. ADHD makes it difficult for people to:

• Manage their behavior.
• Pay attention.
• Control overactivity.
• Regulate their mood.
• Stay organized.
• Concentrate.
• Follow directions.
• Sit still.

Kids usually receive a diagnosis during childhood and the condition often lasts into adulthood. However, effective treatment is available. Left untreated, ADHD can cause serious, lifelong complications.

How common is ADHD?

According to the Centers for Disease Control and Prevention, almost 11% of U.S. children between the ages of 2 and 17 have received an ADHD diagnosis. Worldwide, 7.2% of children have received an ADHD diagnosis.

Boys and children assigned male at birth (AMAB) receive an ADHD diagnosis more than twice as often as girls and children assigned female at birth (AFAB). But this doesn’t mean more boys and children AMAB have ADHD. It just means they present more often with hyperactive-type symptoms and are therefore easier to diagnose.

Types of ADHD

There are four different ways ADHD can present itself. Providers use the kinds of symptoms your child displays to diagnose the condition in one of these four ways.

Predominantly inattentive presentation

Children with this presentation have inattentive ADHD only. Providers previously called this type attention-deficit disorder (ADD). Children with inattentive presentation mainly have difficulty focusing, organizing and staying on track, and have fewer hyperactivity/impulsivity symptoms.

Predominantly hyperactive-impulsive presentation

Children with this presentation show issues with hyperactivity and impulsivity and may show less obvious trouble with paying attention. Hyperactivity means they may fidget, can’t sit still, have a lot of excess energy and are extremely talkative. Impulsivity means they may interrupt others and act without thinking it through first. This is the least common type and typically affects younger children.

Combined presentation

Children with this presentation show at least six symptoms from both of the other types. Symptoms of inattentiveness and hyperactivity-impulsivity present equally. This type is what people most commonly associate with ADHD. About 70% of cases fall under this type.

Unspecified presentation

In these cases, symptoms may be so severe that children clearly demonstrate dysfunction but don’t meet official symptom criteria for a diagnosis of ADHD inattentive, hyperactive/impulsive or combined type. In such cases, providers assign “unspecified ADHD” as the diagnosis.

ADD vs. ADHD

Providers used to call the inattentive presentation type of ADHD “attention-deficit disorder (ADD).” In 1994, the American Psychiatric Association officially changed its name. Providers now call all forms of ADHD “attention-deficit/hyperactivity disorder” whether or not symptoms of hyperactivity are present. As described above, providers diagnose the different types based on the symptoms.

Although the name change happened decades ago, many people still refer to the condition as attention-deficit disorder (ADD). The difference between ADD and ADHD is the former doesn’t include symptoms of hyperactivity or impulsivity.

Signs and Symptoms

There are three main types of ADHD. Providers diagnose the type based on certain presenting symptoms.

What are the symptoms of ADHD?

Your child’s provider will make a diagnosis based on the presence and absence of certain symptoms. The symptoms must have interfered with functioning in at least two areas of life (such as school and home) and have occurred for at least the past six months.

Providers use the signs of ADHD to diagnose and determine the type of condition: inattentive, hyperactive/impulsive, combined or unspecified. The American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition Text Revision (DSM-5-TR™) provides guidelines providers use to make diagnoses.

Predominantly inattentive presentation

ADHD symptoms in kids with inattentive presentation include difficulty focusing, organizing and staying on task. According to the DSM-5-TR, a child with this type must display at least six of the following nine behaviors. (The behaviors must pose a problem in daily activity, at school and at home — not just from time to time, as most children engage in these behaviors.)

• Trouble paying attention to details or making careless mistakes.
• Issues remaining focused on tasks and activities.
• Difficulty listening well, daydreaming or seeming distracted.
• Trouble with following instructions and/or finishing tasks.
• Difficulty with organizing tasks and activities.
• Avoiding or disliking tasks that require continuous mental effort.
• Losing things frequently.
• Easily distracted by outside stimuli.
• Forgetful in daily activities.

Predominantly hyperactive/impulsive presentation

People with hyperactive/impulsive type display the following ADHD symptoms. According to the DSM-5-TR, a child must display at least six of the following nine behaviors. These must pose problems in daily activity.

• Fidgeting with or tapping hands or feet or squirming frequently.
• Leaving their seat when remaining seated is expected.
• Running or climbing when it’s not appropriate.
• Trouble playing or engaging in leisure activities quietly.
• Always seeming “on the go” or “driven by a motor.”
• Talking too much.
• Blurting out answers before questions are completed.
• Frequent trouble waiting for their turn.
• Often interrupting or intruding on others’ conversations or games.

Combined presentation

People with combined type display behaviors from both the inattentive and hyperactive/impulsive categories. According to the DSM-5, children must display at least 12 of the total behaviors (at least six inattentive behaviors and six hyperactive/impulsive behaviors).

Causes

What causes ADHD?

Scientists have identified differences in the brain structure and activity of people with ADHD. The frontal lobe is the front part of your brain, the part behind your forehead. The frontal lobe is responsible for planning, paying attention, making decisions and using language to moderate behavior. Researchers call this kind of activity directed attention. The brains of people with ADHD tend to reach their full maturity at a later time than those of neurotypical people.

People use directed attention to suspend automatic attention, a second kind of attention, which is very strong in people with ADHD. Directed attention, however, takes a lot of effort and is difficult to use. In a person with ADHD, directed attention skills tend to be weaker. Automatic attention is the kind of attention you use when you’re doing something that’s interesting or engaging. Directed attention is the kind of attention you use when you must do something that’s tiring or of low interest. (For example, in childhood, boring, repetitive tasks.)

In addition, nerve cells called neurons transmit signals in your brain. These signals travel through your brain in groups of neurons called networks. Scientists call the automatic attention network in your brain the default mode. They call the directed attention network in your brain the task-positive mode, or your brain’s executive network. Researchers have found major networks that work differently in people with ADHD. Neurotransmitters — chemicals that help transmit signals from one nerve cell to another — also play a role in ADHD.

Although researchers have discovered these brain differences, they don’t completely understand why they occur and lead to symptoms of ADHD. But current research shows that genetics plays a vital role. ADHD often runs in families — a child with ADHD has a 1 in 4 chance of having a parent with the condition.

Other possible causes and risk factors of ADHD may include:

• Lead exposure.
• Brain anatomy.
• Substance use during pregnancy.
• Premature birth.
• Low birth weight.

The following aren’t causes of ADHD:

• Allergies.
• Immunizations.
• Eating too much sugar.
• Too much time staring at screens.
• Poor parenting.
• Social and environmental factors such as poverty.

What are the complications of ADHD?

Without treatment, ADHD can potentially lead to a number of long-term complications. These complications may include:

• Poor self-esteem.
• Depression and anxiety.
• Eating disorders.
• Sleep issues.
• Substance use disorder.
• Risky, impulsive behaviors.
• Frequent driving accidents and injuries.
• Trouble with relationships and other social interactions.
• Academic underachievement.
• Job instability.

Diagnosis and Tests

How to get diagnosed with ADHD

If you’re worried that your child may have ADHD, the first step is to make an appointment with their healthcare provider. Your child’s pediatrician or another specialist can determine if your child has ADHD using a set of guidelines developed by the American Academy of Pediatrics. The guidelines are specifically for children ages 4 to 17. It’s hard to diagnose ADHD in children younger than 4 because they can change very quickly, and many kids at this age are naturally overactive or inattentive. It may also be harder to diagnose ADHD in teenagers due to other conditions they may have, such as depression or anxiety.

There’s no ADHD test to help diagnose the condition. Your child’s provider will take several steps and gather lots of information to help them make a diagnosis. The key factor is multiple people observing the behaviors associated with ADHD in different settings, such as at school and at home. A number of people will be involved in assessing your child’s behavior, including:

• You.
• Your child.
• Your child’s healthcare provider.
• Your child’s teachers and other staff members.
• Your child’s other caregivers.

Based on this reported information, your child’s provider will look at how your child’s behavior compares to other children their age. Noting your child’s symptoms, they’ll also use guidelines found in the DSM-5-TR to help diagnose ADHD. The DSM-5-TR states that:

• Your child’s symptoms must occur in two or more settings (home, school and/or social situations) and cause dysfunction.
• Your child’s provider must identify the presence or absence of six or more symptoms.
• Your child’s symptoms must considerably impair their ability to function in daily activities.
• Their symptoms must have started before they turned 12 years old.
• They’ve had symptoms for at least six months.

After they’ve evaluated your child and their symptoms, they can make a diagnosis along with the type of ADHD. A thorough assessment of behavior is critical (not just neuropsychological testing of attention), as many children who are quite bright may perform well in school even while showing inattentive symptoms.