FOH and bipolar disorder share some symptoms but represent two separate and distinct conceptualizations of mental disorders:
- Bipolar disorder is part of the current system of disorders
- FOH is part of an emerging system of disorders.
- FOH includes mania and depression but also includes many more symptoms which are commonly found in people who experience mania and depression.
Whereas no significant breakthroughs have occurred under the 30+ years of the current bipolar conceptualization, the new perspective brought about by FOH has rapidly led investigators to a detailed hypothesis of the brain circuits and conditions that cause it.
Is FOH a Subtype of Bipolar Disorder?
As you may be aware, there is much controversy surrounding the diagnosis of bipolar disorder in children and much disagreement about the symptoms that should be included in the disorder. FOH evolved out of an attempt to clarify these issues. At first it seemed that the research was leading investigators to the definition of a subtype of bipolar disorder: one which included those children most severely affected by the illness.
But it became clear over time that, by using a newer research approach than that which had led to the current idea of bipolar disorder, investigators found themselves in new territory. The further the research progressed, the less the emerging syndrome was able to be contained under the prevailing concept of bipolar disorder. This was not because it was inconsistent with the DSM criteria for bipolar disorder, but because the very concept of bipolar disorder seemed to become irrelevant under it.
While this statement may seem a bit shocking, it is part of a growing perspective. The opinion is echoed generally at the National Institute of Mental Health where the leadership has recently pronounced that classifications found in the DSM are conceptually flawed and responsible for the lack of progress over the last several decades. (This is discussed under the tab called NIMH; Research Trends.)
Indeed, the new research approach which articulated FOH rapidly pointed investigators to the brain circuitry which can account for the full range of FOH symptoms as well as a suspected physiological deficit which may cause it. This type of progress underscores the inadequacy of the current concepts. In the minds of the investigators, continued use of the bipolar diagnosis is, at this point, counterproductive.
So, to be clear, it is not the case that FOH is a type of bipolar disorder. And it is not the case that FOH stands alongside of bipolar disorder as a separate pediatric disorder. It is much more profound than that. They are ideas of illnesses that exist in two separate spheres of thought. Bipolar disorder is in the old sphere of research and FOH is representative of a new sphere of research. The field as a whole is in transition from one to the other. (see What Is a Brain Disorder?)
Differences between Bipolar Disorder and FOH
Both bipolar disorder and FOH include the symptoms of mania and depression: In both disorders, these are important symptoms. The difference is that in bipolar disorder, mania is the defining symptom of the disorder and it must alternate with periods of depression. (see The DSM Definition of Bipolar Disorder.) When studies are conducted, subjects are included or excluded based on their profiles of episodic mania and depression.
In FOH, while mania and depression are part of the profile, they are not as important. They merely join a robust profile of symptoms that associate with a behaviorally significant, genetically based trait called fear-of-harm. (It is possible that other conditions defined in the future will also incorporate manic and depressive symptoms.) This research, which included a very large number of children at risk for or diagnosed with bipolar disorder, showed that, while mania and depression are very observable and concerning symptoms, they are not very useful from an investigative point of view. To some degree, they have been red-herrings in the search for solutions to this catastrophic illness.
FOH includes a much broader range of symptoms than bipolar disorder. The syndrome unifies the mania and depression of bipolar disorder with many of the symptoms from diagnoses typically considered co-morbid to bipolar disorder. This broader set of symptoms, both behavioral and physiological, not only more accurately reflects the way that our brains create behavior, but it also seems to more accurately match the experience of many children.