You know that horrible, sinking feeling and sleeping difficulties you experience when separated from your mate or significant other for a while? Well, you can partly blame dopamine for that. Partly is the keyword here. That feeling is a type of anxiety. In the same way, anxiety and mood disorders can be affected by a number of brain chemicals including dopamine.
If you have been associating dopamine with all good things in life, and did a double take on that “double-edged-sword” and coupling pleasure with anxiety, you are not the only one. Most of us associate dopamine — a stress hormone and a neurotransmitter produced by the adrenal glands — with pleasure. As a Guardian article put it, “If there were a celebrity. among brain chemicals, it would be dopamine.”
Celebrities and their handlers may show us just their great side to the world, but we should know there is always the other side. And it is not pretty. It’s the same with dopamine, or the “Kim Kardashian of neurotransmitters” as the Gaurdian writer referred to it. Life and biology are not meant to be black and white. Brain chemicals in general are nowhere close to being simple and clear cut. We probably do not know all that we should know about brain chemicals in general and how they work. That applies to dopamine too, even though we do know a lot of things about it.
What we know about dopamine
The main thing we know is that it is a double-edged-sword with implications for both pleasurable and painful things in life. In fact, it seems to be associated with practically everything that matters in life. As Slate writer Bethany Brookshire explains in her recent article “… dopamine has a major role in addiction, whether to cupcakes or cocaine. It plays an important role in lust and love. It’s even important when it comes to movement, motivation, attention, and psychosis.
Dopamine attributes to all of these. But yet, it is none of them; and we shouldn’t want it to be. The complexity of dopamine is part of what makes the chemical so great. It shows us what, with a single molecule, our brains can do.
Yes, with dopamine, as with most other brain chemicals, it seems nothing appears that straight forward.
We have several dopamine systems in our brains
Dopamine functions in the brain as a neurotransmitter, a chemical released by nerve cells in order to send signals to other nerve cells. It operates via a number of distinct dopamine systems, or specialized groups of cells originating in the midbrain. To sum up all the functions of dopamine is to say that it helps prepare the brain to think, move and anticipate rewards.
The different branches of the dopamine system have been associated with uniquely specific functions.
Dopamine facilitates movement
One branch that goes to the striatum of the brain facilitates movement. This is the part of the dopamine system involving Parkinson’s disease. Low levels of dopamine are found in those who have Parkinson’s disease, which in turn, affects their capacity for movement.
It plays a key role in reward systems and addiction
The most well known among these dopamine systems is the one associated with reward motivated behavior, and yes, you guessed it, addiction. This goes from the midbrain to the limbic system or the emotional center of the brain which regulates our emotional responses. The reward center of the brain, or the neucleus accumbens, is involved in how the brain operates the reward dopamine system.
Dopamine modulates cognitive functions, including learning and memory
Another important branch of the dopamine system goes to the frontal cortex of the brain and helps modulate cognitive functions. Its role there is on enhancing the efficiency of certain forms of thinking and working memory. As John Medina, author of Brain Rules explains it, “The amygdala is chock-full of the neurotransmitter dopamine, and it uses dopamine the way an office assistant uses Post-It notes. When the brain detects an emotionally charged event, the amygdala releases dopamine into the system. Because dopamine greatly aids memory and information processing, you could say the Post-It note reads “Remember this!” Research shows that the Post-It note may also indicate whether what is called for is pleasureful emotional learning or fearful emotional learning.
Dopamine affects how we respond to stress
But that is only one part of the story. Your amygdale allows you to feel rage, fear and pleasure. It is also the center for memories of your past experiences with fear, rage or pleasure. It’s what makes you nervous about the rustle of leaves in the bush, which could be an indication of a crouching tiger in the savannah; or the container truck hurtling towards you on the wrong lane. It’s the fearful emotional learning that makes you nervous at hearing sound even in places you know there is little potential for harm.
Either way the dopamine signal is prompting you to take action. As Ahmad Hariri, a neuroimaging expert at the University of Pittsburgh School of Medicine, explains, “In simple terms, the amygdala is influencing anxiety. It’s working to let you know that there’s something out there that may or may not be important for your survival.” Once stimulated by the amygdale, and supported with feedback from your autonomic responses, your prefrontal cortex has to determine what to do next, and in the process get your amygdale to quiet down. A damaged amygdala inhibits such anxiety. A rat with an experimentally damaged amygdala will walk towards a sleeping cat. People with damaged amygdale show only blunted responses to things that would normally arouse emotional reactions.
Lower levels of dopamine are often associated with higher levels of anxiety
Hariri was a participant in a study published in Nature Neuroscience which explored the dopamine amygdale links to anxiety. The study showed that when people have higher dopamine levels that strengthen the communications between it and the prefrontal cortex, they are less likely to experience stress and anxiety. Those with lesser integration are more likely to find life stressful. They score higher on “trait anxiety,” the baseline anxiety level that’s associated with an individual’s personality.
Types of anxiety
Anxiety is a normal response to a stressful situation. But if stress is ongoing, or excessive, the stress hormones that flood our body and brain can wreak havoc on both our physical and mental health. In some people this may lead to anxiety disorders.
An anxiety disorder is experiencing too much anxiety that the person is unable to control, and it affects their ability to go on with their normal life. National Institute of Mental Health lists a number of anxiety disorders including generalized anxiety disorder, obsessive-compulsive disorder, panic disorder, post-traumatic stress disorder, and social phobia (or social anxiety disorder). It must be noted that not everyone who undergoes acute or chronic stress develops anxiety disorders. This is an indication that factors other than stress are at play in their development. Stress is just one factor.
Dopamine is the not the only factor leading to anxiety
The biochemistry of anxiety is complicated. You cannot blame all anxiety on dopamine. There is research pointing to nearly every type of neurotransmitter and hormone showing how it can play some role in anxiety.
Serotonin, the most well-known among neurotransmitters, has been associated with anxiety. Low levels of serotonin have been linked to both anxiety and depression. Thyroid hormone has been linked to severe anxiety and panic attacks when there is an overproduction of thyroid hormone. Treating hypothyroidism improves anxiety levels with immediate effect. The neurotransmitter gamma-aminobutyric acid, better known as GABA, has been strongly associated with mood disorders with high levels leading to mood boosting and low levels of GABA having an excitatory effect putting people on edge. Norepinephrine is responsible for many symptoms of anxiety. Endorphins, which are considered mood relaxers and stabilizers, are responsible for addictions that people use as coping tool when under stress.
Dopamine is the late comer to the anxiety party
Scientists are still working on how it relates to anxiety.
Some studies have shown that people with social anxiety seem to have problems with their dopamine receptors. There is evidence that improving dopamine levels will reduce anxiety disorders including social anxiety disorder.
We have a lot to learn about how brain chemicals work
We still have to learn exactly how the levels of brain chemicals fluctuate. Genetic and environmental factors both apply. It is also possible for our emotions and our responses to have an effect on these hormone levels. What makes this task even more challenging is the fact that brain chemicals have complex interactions among them. As The Scientific American noted in an article—Mood Drug Can Both Cause and Relieve Anxiety— “mood disorders do not result from a simple chemical imbalance—too much or too little of one neurotransmitter—but rather from subtle changes in many systems in the brain.”
The article was about corticotropin-releasing hormone (CRH) which has long been associated with anxiety and the failure of a drug developed to block its actions in the brain. But, the story may as well apply to most other brain chemicals as well, including dopamine. As Jan M. Deussing, a molecular biologist at the Max Planck Institute of Psychiatry in Munich explains, “The network is much more complex than we thought before.”
Why it hurts to be away from your partner
As for why it hurts to be away from your partner, it’s an evolutionary thing resulting from the pair bond need that first began with our parent-child bond. This also explains why we feel romantic attachments very strongly. Scientists have shown that the same neurochemicals—oxytocin, vasopressin and dopamine—are involved in both relationships. It seems that the behavioral patterns that are associated with parental and romantic bond formation and separation are also similar. In other words, we are dealing with a form of adult separation anxiety!
As social psychologist Lisa Diamond from the University of Utah explained to the Scientific American, we may think about parent-child relationships and adult romantic relationships as being fundamentally different. However, “it really boils down to the same functional purpose: creating a psychological drive to be near the other person, to want to take care of them, and being resistant to being separated from them.” Diamond’s research that led to the article was about high corticosterone levels in prairie voles when separated from their partners. The human equivalent is cortisol, a human stress hormone. This means that scientists are at last beginning to unravel why it hurts to be away from our partners.
We have a long way before understanding fully the biochemistry of anxiety that would reveal how we should best treat different types of anxiety. How exactly dopamine can help treat anxiety is not clear either. Ahmad Hariri, a researcher of the dopamine-anxiety connections put it this way, “One can imagine in the distant future the development of a drug that selectively enhances dopamine signaling in the amygdala, leading to decreased anxiety.”
Call me when the drug to stop separation anxiety has been discovered. Until then poetry, meditation and wasting time on Facebook will have to do.