Some experts in the field contend that the brain science behind bipolar disorder is just now beginning to mature and it actually lags behind the knowledge of other mental disorders. One reason for the lagging science is that more than one part of your brain is likely involved, and scientists and doctors also believe there is not a single cause for the disorder.
What is Bipolar Disorder?
Bipolar disorder is considered a chemical imbalance, and as mentioned, more than one part of the brain is likely involved. The National Institute of Mental Health defines Bipolar as “unusual shifts in mood, energy, activity levels, and the ability Synapse xt to carry out day-to-day tasks.” While that definition provides some insight into what bipolar disorder is, it does not describe what is actually occurring in the brain and why there is not one medication to help control the disorder.
What Occurs in the Brain of a Bipolar Individual
The cerebrum (top or main part of your brain) gathers and processes information, making connections, generating thoughts, and even controlling emotions. The prefrontal cortex, which is part of the cerebrum, is thought to play a major role in the emotional overreactions of someone with bipolar disorder. This area of the brain also seems to get the most attention in the literature, so it could be the main part of the brain creating problems for someone with the disorder.
The middle of the brain (that sits behind your temple and above your ear) is also involved. It contains the thalamus and hypothalamus. They maintain things such as sleeping, eating, and appetite, which also impact episodes and symptoms of the disorder. And, as of yet, no one knows whether the cerebellum (back of the brain near your spinal cord) plays any role in bipolar disorder, as its main function has more to do with complex movements.
Neurons carry signals from your brain to your body and transmit electrical impulses for chemicals to be released. Our brain needs certain chemicals to function normally. Bipolar disorder is the result of an imbalance in these chemicals, and there are at least two brain chemicals, or neurotransmitters, thought to be involved – serotonin and dopamine.
Serotonin helps regulate mood, anxiety, fear, sleep, body temperature, and the rate at which your body releases certain hormones. Dopamine is primarily linked to feelings of pleasure, and it also regulates attention and focus along with some muscle movements.
The signals being sent by the neurons are the neurotransmitters themselves (the chemicals of serotonin and dopamine). As mentioned, they are responsible for maintaining many things such as sleep, anxiety, fear, pleasure, and the overall regulation of your moods and hormones. But, there is a region between two neurons called the synapse, which is a structure that allows one neuron to pass a chemical signal to another neuron.
The synapse in a bipolar individual is what prevents the two neurons from communicating properly. So, what happens is that one neuron sends the signal, and the other neuron is supposed to receive it and then respond to the message with either excitement or inhibition in a “normal” manner. But, for some reason, the synapse region does not allow for this to happen properly, which leads to the mania and/or depressive mood states.