Dr. Daniel G. Amen is a child and adult psychiatrist who came up with a classification for ADHD:
Type I - Classic ADD (ADHD)
Type II - Inattentive ADD
Type III - Over-Focused ADD
Type IV - Temporal Lobe ADD
Type V - Limbic ADD
Type VI - "Ring of fire" ADD
Did you ever hear of "Ring of Fire"? It is also referred as the "Bipolar Disorder ADHD". The Ring of Fire type draws characteristics from the other types of Attention Deficit Disorder. They can be hyperverbal, they can get stuck in loops of negative thought and can display obsessive or ritualistic behavior. They can be overly sensitive and prone to temper outbursts. A unique characteristic of the Ring of Fire is that this type tends to be overly sensitive to light, sound, taste, or touch.
Also, the person with this type of ADHD does nothing in a subtle way and has manic qualities that can be very difficult to manage. They don't just talk often, they talk nonstop. They're easily distracted, aggressive, oppositional, and moody. They're also inflexible and can be quite oppositional.
These are some brain scans of children and adults with Ring of Fire ADHD:
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