ADHD Causes

We do not know exactly what causes attention deficit hyperactivity disorder (ADHD).

• Although external factors, such as problems in growth and development in the womb, heavy drug use, and lower socioeconomic status, have been linked to some cases of ADHD, it is mainly a biological disorder. In other words, it is mostly a person's genes that determine whether he or she has the disorder.
  
  
• ADHD symptoms may be affected by, but are not caused by, television, video games, sugar or other foods, food allergies, bad parenting, bad schools or teaching, or a disruptive home life.

Genes that control the levels of chemicals in the brain called neurotransmitters seem to be different in ADHD, and levels of neurotransmitters are out of normal balance.

• MRI and other imaging studies suggest that these imbalances occur in parts of the brain that control certain types of movement and executive functions.
  
  
• These areas of the brain may be smaller and/or less active in people with ADHD.

The 6 major tasks of executive function that are most commonly distorted with ADHD are the following:

• Shifting from one mindset or strategy to another (that is, flexibility)
  
  
• Organization (for example, anticipating both needs and problems)
  
  
• Planning (for example, goal setting)
  
  
• Working memory (that is, receiving, storing, then retrieving information within short-term memory)
  
  
• Separating emotions from reason
  
  
• Regulating speech and movements appropriately