What are the causes of Bipolar Disorder
Bipolar disorder (BPD) is a mental condition that causes extreme shifts in a person’s mood, energy levels, thinking, and behavior. While we all have our ups and downs, the severe mood swings characterized by bipolar disorder are so significant that they impair a person’s ability to function for days, weeks, or even months.
Formerly known as manic depression, bipolar disorder causes a person to experience emotional highs (mania) and lows (depression), or combinations of the two (mixed episodes). The symptomatic features of bipolar disorder fall along a continuum, where each case can vary from person to person.
In some cases, a person struggling with the symptoms of bipolar disorder will experience frequent mood swings, while some may only experience a few in their lifetime. This spectrum is what contributes to the difficulty in the diagnosis and treatment of bipolar disorder; often times people are misdiagnosed with another disorder due to overlapping symptoms. Bipolar disorder is a progressive disorder that gets worse over time if left untreated.
Symptoms of Bipolar Disorder
Generally speaking, there are four types of mood-disruption symptoms that characterize bipolar disorder:
- Mixed episodes
Symptoms of Mania
When someone with a mood disorder is experiencing a manic episode, they will have heightened levels of energy, often times boosting the person’s creativity and creating a sense of euphoria. The hyperactivity associated with mania can cause you to feel invincible, giving the illusion that you can accomplish anything, and that you are destined to achieve all things considered.
Mania may seem like an appealing feature at first, but manic episodes tend to spiral out of control. When experiencing mania, a person might engage in very unusual or reckless behavior, like spending large sums of money or making inappropriate sexual comments. If left untreated, manic symptoms can last for up to three months and can be dangerous for the individual and those around them.
Some of the common signs and symptoms of mania include:
- Feeling unusually optimistic or “high” OR feelings of extreme irritability and increased aggression
- Little to no sleep
- Sustained high energy levels
- Racing thoughts; jumping from one topic to another
- Easily distractible
- Quick speech or rambling
- Increased impulsivity
- Impaired judgment
- Reckless or aggressive behavior
- Delusions or hallucinations (in severe cases)
Hypomania is a less severe form of mania in that it is characterized by many of the same symptoms but in a less severe form and over a shorter period of time. In a hypomanic episode, you still experience feelings of euphoria and have increased amounts of energy, but the symptoms of psychosis or detached reality are not present. These feelings won’t necessarily affect the person's ability to carry on day-to-day tasks, and to others, it would simply appear as though you’re in an unusually good mood.
That being said, episodes of hypomania can still cause a person to engage in poor judgment and dangerous decision making, putting relationships, among a number of other things, at risk. Hypomania may also be the first step towards a full-blown manic episode or can be followed by a major depressive episode.
For someone with BPD, the severe symptoms of experiencing a major depressive episode cause a noticeable difficulty in the ability to carry out day-to-day tasks. Symptoms of depression can negatively impact school or career performance, social activities, relationships, and even the ability to follow basic hygiene.
The common signs of depression include:
- Intense feelings of sadness, hopelessness, and irritability.
- Loss of interest or pleasure in almost all activities
- Excessive sleeping or insomnia
- Fatigue and loss of energy
- Increased feelings of guilt and worthlessness
- Decreased concentration
- Either slowed behavior or restlessness
- Suicidal thoughts or plans
In a mixed episode, symptoms of both depression and mania can be present at the same time. A mixed episode can also progress to either a pure manic or depressed state. The back-and-forth emotional deregulations are why the risk of suicide is greatest during this stage.
Rapid-cycling refers to a pattern of frequent and rapidly-occurring fluctuations of episodes exhibited during the course of bipolar disorder. Someone that qualifies as being in a state of rapid-cycling experiences four or more episodes of mania or depression within a given year. This manifested form of BPD may come and go over time and can occur at any point throughout the disorder.
Types of Bipolar Disorder
Although bipolar is known to present itself in many different ways, there are four main types of BPD that are each characterized by a unique set of symptoms: Bipolar I, Bipolar II, Cyclothymia, and Other or Unspecified Bipolar.
Bipolar I is seen as the most classic form of the manic-depressive disorder, in that a person will experience at least one mixed or manic episode. The manic episodes typically last at least 7 days, and some symptoms can be so severe that the person may need to be hospitalized. Mixed episodes where both hypomanic and depressive symptoms are present is a common feature of bipolar I. Although not in all cases, bipolar I usually involves at least one depressive episode, lasting about 2 weeks.
Bipolar II is characterized by a pattern of depressive and hypomanic episodes, but full-blown manic episodes are not experienced.
Cyclothymia is defined by cyclical mood swings that occur on a fairly regular basis. The symptoms of hypomania and depression in this type of BPD are typically less severe in form but can still have a serious negative impact on a person’s life. Cyclothymia can also progress into full-fledged manic or depressive episodes.
Causes and Triggers of Bipolar Disorder
There is a lot of uncertainty surrounding the cause of bipolar disorder, but scientific research suggests that the onset of these mood disorders likely results from a multitude of factors and the interactions that occur between them.
Bipolar disorder is known to run in families, but genes are not the only thing at play here. While some inherit a genetic vulnerability to the disorder, many with the same genetic predisposition never develop the illness. This alone shows that there are other factors aside from genes that are responsible.
Environmental factors, such as stress or loss can act as triggers creating new episodes or exacerbating existing symptoms. Sleep deprivation and substance abuse are also known to trigger and exacerbate symptoms of BPD. The variations in severity coupled with the interplay of biological, genetic, psychological, and psychosocial elements are what cause these disorders to be so complex, and therefore difficult to treat, especially when substance abuse and bipolar disorder are combined.
The Brain and Bipolar Disorder
Given its vast complexity, our understanding for the brain’s interworking mechanisms remains quite limited. New theories about communicative neural processes arise as science continues to progress—keeping the field of abnormal psychology and the way we treat mental health disorders always changing.
In cases of bipolar disorder, it’s pretty clear that emotion seems to overtake behavior, but new research has given us a glimpse into the processes and mechanisms by which this happens: the brain’s emotional centers are exhibiting too much activity, whereas the judgment and impulse control centers (located in the frontal lobes) exhibit too little. This has led experts to believe that much of bipolar disorder’s underlying cause resides in the circuitry of the brain that contributes to our overall functionality.
Brain chemicals called neurotransmitters serve as the messengers within these circuits; they travel through our brain’s neural pathways to allow different parts (or “hubs”) to communicate with one another. Neurotransmitter imbalances disrupt and alter the communicative routs between brain cells, causing impairment to processes such as mood regulation upon which we rely and ultimately the attributes that make us who we are.
The three key neurotransmitters responsible for brain and bodily function, noradrenaline (norepinephrine), serotonin, and dopamine, are believed to play an important role in the onset of BPD. Serotonin is known to regulate and control processes such as sleep, wakefulness, memory, eating, sexual activity, learning, and impulsivity Abnormalities in serotonin levels and disruptions to the neural pathways that communicate via serotonin explain some of the behavioral symptoms associated with BPD.
Dopamine is responsible for regulating the reward center of the brain and controls feelings of pleasure. Disruptions to dopamine circuitry can cause a number of unusual symptoms, including those seen in people with BPD. Abnormal levels of dopamine in the brain can cause the delusions and hallucinations like those exhibited in episodes of psychosis and by people with schizophrenia.
Researchers have found various physical differences in the brains of people with BPD as well. It’s known that the prefrontal cortex (largely responsible for judgment, decision-making, and impulsivity) shrinks in size as bipolar disorder progresses. Science suggests that these differences in brain size increase with each episode of severe mood disturbance. Luckily, there are medications that can reverse these effects, lithium being one that reduces frontal atrophy.
Some studies have shown there to be a large genetic component to bipolar disorder, as BPD has a tendency to run in families. More than two-thirds of people struggling with bipolar have a family member that also have some kind of mood disorder.
Studies that analyze identical twins have proven to be most convincing. Data have shown that if one identical twin has BPD, the other twin has a greater chance of developing the disorder more than any other sibling in the family. In fact, the chance of the twin developing bipolar disorder at some point in their lifetime is around 40 to 70 percent.
Another interesting point to consider is the heritability of bipolar I versus bipolar II. Researchers at John Hopkins University looked at the immediate family members of patients diagnosed with bipolar I and bipolar II and found bipolar II to be the most common type present in both sets of families. Of the 47 relatives of bipolar II patients, 40 percent of them also had bipolar II disorder.
Although our genetics are an important factor in determining one’s chances of developing bipolar disorder, our environment and the way in which we respond to stress plays an important role as well. Children who grow up in hostile or abusive home environments are more prone to develop mood disorders, especially those that have a genetic predisposition to BPD.
Children with a bipolar parent are especially at risk; these children may have a parent that experiences frequent mood swings or struggles with substance abuse. Sometimes parents that refrain from taking medication engage in risky behaviors, which could lead to financial troubles or recurrent hospitalizations.
Inability to control moods can lead to constant verbal or even physical abuse, all of which can have profound effects on a child psychologically, can also be long-lasting. BPD usually presents itself in late adolescence or young adulthood, but violent and stressful living environments experienced as a child can trigger moods swings that manifest later in life.
Many people with BPD struggle with sleep difficulties that can exacerbate symptoms of both depressive and manic episodes. Studies have shown these individuals to have genetic predispositions to disrupted sleep-wake cycles. Often times the loss of sleep can trigger manic symptoms in some patients, whereby the thought alone of not being able to sleep furthers the cycles of anxiety and rumination, keeping the person awake. Despite being sleep-deprived, feelings of needing sleep decrease even more in a manic state.
In a national study, about 56 percent of people diagnosed with BPDA experienced drug or alcohol addiction at some point in their lifetime. Although it may not be a cause of BPD, substance abuse frequently co-occurs with BPD and can worsen the symptoms of an episode, along with the overall course of the disorder.
Drugs such as alcohol or tranquilizers can trigger symptoms of depressive episodes, whereas stimulants like cocaine, amphetamines, or ecstasy trigger symptoms of mania. Unfortunately, many turn to drugs or alcohol as a form of self-medicating to weaken the painful feelings of emotional dysregulation but end up intensifying the effects in the process.
Substance abuse is also known to cause alterations in brain chemistry, especially in cases of chronic use. Even a person with a clean bill of health can develop bipolar disorder from frequent drug use. A dual diagnosis of BPD and substance abuse is very difficult to treat, given that many of the symptoms overlap. It’s important to understand the risks associated with drug use, especially those that are diagnosed with or have the potential to develop bipolar disorder.
There is no known cause for bipolar disorder but there are many factors that play into its development. Some are more susceptible than others, which could be due to either genetic or environmental factors, or both. Bipolar disorder is known to run in families, but there are some people with this predisposition that never end up developing the disorder, adding to the ambiguous etiology of BPD.
Advances in science and medicine continue to shift the ways in which we conceptualize and treat physical and mental illnesses. Modern technology has allowed researchers to develop significant insight into psychopathology and our state of consciousness. If you or a loved one suffer from bouts of depression or manic episodes, contact your doctor and seek help.