The medical industry still doesn't know where bipolar disorder comes from. Research says that a combination of things can cause it. They think it can be genetic (inherited by family), biological (the structure and function of your brain is different) or affected by health, life-style, environmental and circumstantial factors.
Bipolar disorder causes abnormal mood changes; difficulty to focus or concentrate; changes in energy and activity levels; and it can make it difficult to do simple things in life. Bipolar can happen unexpectedly (episodic) and it is chronic spanning over a number of years to a lifetime.
Apparently the structure and chemical changes in your brain are different to people without Bipolar Disorder. At the moment a diagnosis is made by symptoms and not brain imaging or other diagnostic tests. Other research points to neurotransmitter imbalances, abnormal thyroid function, circadian rhythm (sleep-wake cycle) disturbances, and high levels of the stress hormone cortisol.
Researchers believe it can be inherited as it appears to run in families. They suggest that many genes may be involved that cause this disorder. It doesn't mean that your children will develop Bipolar, even if there is a history of bipolar in the family.
Studies show that one twin can have bipolar and the other not. This suggests that bipolar can be environmental rather than genetic. High levels of anxiety, eating disorders, ADHD, substance abuse and physical conditions such as the thyroid, multiple sclerosis, Cushing's disease, heart disease or obesity can lead to symptoms of bipolar disorder.
Sometimes the messages that are sent by the neurons in your brain which are carried by the neurotransmitters across your neural circuit can cause effects in your mood and body that you don't always want. There are three chemicals that I am going to share with you that can cause mental and physical distress if the balance of these chemicals are not healthy. These chemicals can affect your mood and can cause stress and anxiety.
These (and possibly other) chemicals can lie dormant. They can activate on their own or be triggered by outside things psychological stress, social conditions and environmental changes.
A neuron is like your computer. It can receive, process and send millions of messages in seconds. It is a nerve cell that gets its information from electrical and chemical signals so that it can talk other cells.
A neurotransmitter is like a wire connected to your Internet router. It sends encrypted messages from one computer (neuron) to other computers on the Internet (target neurons).
A brain (or neural) circuit is like the Internet. It has many computers (neurons) connected to each other across wires (neurotransmitters) which send and receive messages so that the brain and body can function.
Noradrenaline (norepinephrine) is a hormone and a neurotransmitter that can trigger your fight-or-flight response when you are stressed. It helps with being alert, increases getting and forming memories, focuses your attention. It can also make you restless and anxious depending on your environment.
Serotonin is a neurotransmitter that is connected to changing the way you think, feelings of health and happiness, sleep, being awake, eating, sexual activity, impulsivity, reward, learning, memory and physiological processes - body functions.
Dopamine is a neurotransmitter that sends messages to control pleasure, emotional reward and motor control.