Types of ADHD: Making the Diagnosis
In some people, the signs of ADHD seem obvious -- fidgeting constantly, difficulty paying attention in school or at work, and leaving tasks unfinished. For others, particularly those without behaviors problems, ADHD may be more difficult to diagnose.
The symptoms of ADHD may mimic those of other conditions, and sometimes the signs are subtler and harder to distinguish. One psychiatrist, Daniel Amen, MD, believes that to get a truly accurate diagnosis of ADHD, it is necessary to look inside the brain to see how well various areas are functioning. He has developed his own set of ADHD subtypes based on brain scans of children with ADHD, which he says can better target treatment and determine whether it's working.
How Is ADHD Usually Diagnosed?
Most psychologists, psychiatrists, and pediatricians diagnose ADHD based on a series of inattention and hyperactivity symptoms outlined in the Diagnostic & Statistical Manual for Mental Disorders-Fourth Edition-Text Revision (DSM-IV-TR). For someone to be diagnosed with ADHD, the behaviors must have lasted for at least six months, and be severe enough to disrupt school and other aspects of the individual's life.
Inattention symptoms of ADHD include:
- Not paying attention to detail
- Making careless mistakes
- Failing to pay attention and keep on task
- Not listening
- Being unable to follow or understand instructions
- Avoiding tasks that involve effort
- Being distracted or forgetful
- Losing things that are needed to complete tasks
Hyperactivity-impulsivity symptoms of ADHD include:
- Getting up often when seated
- Running or climbing at inappropriate times
- Having trouble playing quietly
- Talking excessively or out of turn
Based on the above symptoms listed in its Diagnostic and Statistical Manual, the American Psychiatric Association has identified three subtypes of ADHD:
1. ADHD, Combined Type: Both inattention and hyperactivity-impulsivity symptoms
2.ADHD, Predominantly Inattentive Type: Inattention, but not enough (at least 6 out of 9) hyperactivity-impulsivity symptoms
3. ADHD, Predominantly Hyperactive-Impulsive Type: Hyperactivity-impulsivity, but not enough (at least 6 out of 9) inattention symptoms
ADHD Diagnosis Based on Brain Scans
Daniel Amen, MD, a child, adolescent, and adult psychiatrist who serves as medical director of the Amen Clinics in California, Washington, and Virginia, has used a combination of symptoms and brain scans to come up with his own types of ADHD.
Amen considers these to be the hallmark symptoms of ADHD:
- Short attention span
- Poor internal supervision
Based on these symptoms, and the use of brain scans to measure blood flow (SPECT), to highlight activity in the parts of the brain related to attention, short-term memory, and forethought, Amen described these six types of ADHD:
- Type 1 -- Classic ADHD. Symptoms of ADHD, plus hyperactivity and impulsivity; responds well to stimulant medications
- Type 2 -- Inattentive ADHD. Features of ADHD, but instead of hyperactivity, there is low energy; responds well to stimulant medications
- Type 3 -- Overfocused ADHD. Symptoms of ADHD and negative thoughts and behaviors, such as opposition and arguing; tends to respond better to an antidepressant (such as Prozac) combined with a stimulant
- Type 4 -- Temporal Lobe ADHD. The hallmark features of ADHD, plus irritability, aggressiveness, and memory and learning problems; responds better to antiseizure medications (like Neurontin) than to stimulants
- Type 5 -- Limbic ADHD. Combines ADHD with depression and low energy and decreased motivation; responds better to stimulating antidepressants than to stimulants
- Type 6 -- The Ring of Fire. Cross between ADHD and bipolar disorder; characterized by moodiness, aggressiveness, and anger; Anticonvulsants or newer antipsychotic medications tend to work better than stimulants