The kindling effect was originally discovered through research of epilepsy. It was first discovered by accident by researcher Graham Goddard in 1967. It is characterized by the disorder getting worse over time with each seizure, which is usually triggered by physical stresses or chemical changes to the cells of the brain.  Now research shows that the kindling effect may be present in people with Bipolar Disorder as well.


In epilepsy, it is thought that with every seizure the brain becomes more sensitized and eventually memorizes what triggered the seizures; thus, future episodes can occur independently of an outside stimulus.[1]


The way it is thought to work in bipolar disorder is that the person's episodes will get worse over time, as the brain recognizes triggers, such as stress.  This is worse in untreated bipolar disorder.


The name "kindling" was chosen because the process was compared with a log fire. While logs themselves are used to start the fire, smaller pieces of wood (called kindling) are used to help the bigger logs catch fire.   Dr. Robert M. Post of the National Institute of Mental Health (USA) is credited with first applying the kindling model to bipolar disorder (NARSAD).


Demitri and Janice Papolos, authors of The Bipolar Child, describe this model as follows:

"... initial periods of cycling may begin with an environmental stressor, but if the cycles continue or occur unchecked, the brain becomes kindled or sensitized - pathways inside the central nervous system are reinforced so to speak - and future episodes of depression, hypomania, or mania will occur by themselves (independently of an outside stimulus), with greater and greater frequency."

Many researchers now believe that the kindling effect now applies to both rapid-cycling bipolar disorder and to treatment-resistant bipolar disorder.

This theory has been borne out by research observations. For example, "there is evidence that the more mood episodes a person has, the harder it is to treat each subsequent episode..." thus taking the kindling analogy one step further: that a fire which has spread is harder to put out (Expert Consensus, 1997).[2]


In addition, substance abuse – such as the use of cocaine and/or alcohol – can be a definite contributing factor in the kindling effect in bipolar disorder.