Is behavioral disorder a mental illness?

While there is a close connection between behavioral disorders and mental illness, the two are not the same thing. The National Institute of Mental Health (NIMH) defines a mental illness as a behavioral, mental, or emotional disorder. Basically, mental illness is considered a subset of the behavioral disorder category.

A behavioral disorder covers a broad range of issues. Because behavioral disorders include a pattern of repetitive behaviors, they can occur for a variety of reasons and lead to many deeper issues. Common behavioral disorders that lead to inattention, drug use, criminal acts, or secrecy, could be caused by a variety of mental illnesses.

Mental illnesses, on the other hand, are usually more specific types of behavioral disorders. They are the underlying cause of behavioral issues in those affected.

Common mental illnesses include things like:

  • Depression

  • Social anxiety

  • Panic disorder

  • Severe phobias

  • Obsessive-compulsive disorder (OCD)

  • PTSD

  • Eating disorders

  • Psychotic disorders

Each of these conditions is caused by internal and external factors and results in severe and unusual behavioral changes that could become dangerous for those affected and for their loved ones.

Parent quiz: Child mental health checklist

This 3-minute, online quiz can be used if you think your child is having emotional, attentional, or behavioral difficulties.


Need to find a therapist near you? Check out the Monarch Directory by SimplePractice to find licensed mental health therapists with availability and online booking.



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