You know you read too many research papers when you have a favorite "brain abnormality." Guilty as charged! Years ago I began collecting a list of brain abnormalities associated with bipolar disorder. Primarily, I used this list to help teachers, family and friends "see" the physical nature of the illness. When I wrote The Childhood Bipolar Disorder Answer Book, I threw out my first list and started from scratch with the documented brain abnormalities found specifically in childhood-onset bipolar disorder. As I did all this research, I came across an incredibly fascinating brain abnormality that was found at a higher rate in adults who had childhood-onset bipolar, but not in adults who had later onset. This was intriguing to me. In my book for teachers, I share more about this abnormality. The following is an excerpt from SWIVEL to Success.

The Fascinating Septum Pellucidum

The septum pellucidum is a triangular shaped membrane that lies deep within the brain and separates the right and left hemispheres of the brain. It is actually made up of two distinct membranes. When a baby is born these membranes are separate, having a small space between them. As a baby grows the two membranes fuse together to form one. Why should we care about this membrane? It is thought to be a relay within the limbic system. The limbic system is an emotional circuitry of sorts. It’s made up of the parts of the brain that are involved in emotion, motivation and the emotional association of memory. Several of the previous brain areas that we talked about are included in the limbic system. The fascinating thing about these two small membranes is that by the time an infant is 3-6 months old these membranes fuse together as one … or at least they are supposed to. When these membranes don’t fuse together there is a cavity left between them. A tiny cavity may not be considered abnormal but in adults who had a childhood onset of bipolar disorder this cavity was not only present at a higher rate but also enlarged. This was different from adults who had onset of bipolar disorder later in life. Whenever there is an enlarged cavity between these two membranes it’s called “cavum septi pellucidi” and it is strongly correlated to neuropsychiatric disorders including bipolar disorder.

So what’s the big deal? The big deal is that this abnormality always begins in infancy. I am not suggesting that doctors can diagnose or treat an infant for bipolar disorder. But long before the child grows and shows the full range of symptoms that will lead to the diagnosis of bipolar disorder, we are still parenting and teaching this child who may already be experiencing an abnormality deep within the brain – an abnormality that began before he could even walk or talk.