Monitoring Dopamine Levels in the Brain
Have you ever wondered about the effects of increasing dopamine levels or how your dopamine levels compare to that of your friends and family? Or imagined how great it would be to start your day with a quick brain scan to monitor the state of your brain’s chemistry?!? Ok ok, so if you’re like most people, you probably haven’t given much thought to your own brain chemistry let alone anyone else’s, but you can humor me, for now, as I imagine how exciting it would be to learn the state of our neurotransmitters and receptors, and the quantities and areas of their availability in the brain. But why should we care about any of this?
Dopamine Levels Affect Quality of Life
Dopamine affects our brains in so many ways and some of the symptoms that result from too little or too much dopamine can seriously impact the quality of our lives.
Parkinson’s Disease and Loss of Dopamine Receptors
Take Parkinson’s Disease for example, which is associated with a loss of dopamine receptors in the substantia nigra making dopamine less available for areas that require it. (Don’t worry too much if you don’t know what all these words mean, you can just “blah blah” over them for now, and refer back later if you want to know more.)
Does Dopamine Effect Creativity?
Quite possibly, increasing dopamine levels in the ventral tegmental area of your mesolimbic pathway could help you feel a little more like a creative genius… or maybe just schizophrenic, but at least you would KNOW, right?
Dopamine and Depression
And if you or a friend was feeling sluggish and depressed, that brain scan just might give you a clue if it was dopamine related.
Unfortunately, brain scan technology isn’t as cheap or common as the average toothbrush, so it’ll probably be a while before we can monitor the effects and function of our dopamine systems, but in the meantime, here are some of the questions I have been researching.
If you wanted to increase dopamine levels, how would you do it? Would you go the drugless route and boost dopamine by adjusting your diet? Would you supplement with a dopamine precursor such as l-tyrosine? Or would you go to your doctor to learn if increasing dopamine with the latest smart drug or antidepressant is best for you? With a busy day ahead of you perhaps a little extra dopamine is just what you need to stay motivated and energized (and to the students reading this, get through that research paper) …or is it?
What is Dopamine?
Dopamine is an important catecholamine neurotransmitter needed by Dopaminergic neurons located in the arcuate nucleus, substantia nigra, and ventral tegmental areas of the brain. The ventral tegmental area of the midbrain is involved in rewards, motivation, and is associated with intense emotional states. The arcuate nucleus in the hypothalamus is involved with lactation and issues like amenorrhea in women. In the substantia nigra, dopamine is linked to addiction, reward, and physical activity. Parkinson’s Disease is linked to the death of dopaminergic neurons located in the substantia nigra, but more on that below.
Dopamine is also the precursor of two other catecholamine neurotransmitters: norepinephrine and epinephrine (adrenaline) both used in the fight-or-flight response to trigger the release of glucose. Catecholamines, including dopamine, increase the blood supply to major organs like the heart and brain. This causes the heart rate to accelerate, blood pressure to rise, and makes you feel stronger and more mentally alert. Interesting to some, being cold can also cause catecholamine levels to rise, which may explain why some people do crazy things like take a cold plunge in icy waters in the winter (which by the way could be very dangerous if you have a heart or blood pressure issue…or don’t know how to swim..)
Dopamine Effects and Function
So what does dopamine do? Basically, dopamine is like the brain’s motivation/reward messaging system because it kick starts your ambition and makes you want to do something in this world. It’s a bit like dangling a carrot in front of a horse, or watching a cat chase a string. When pleasure or something desirable is almost within reach, it creates this expectation that it could be obtained if we just did something, i.e. …”it’s right there, just a little further… one more surprise pounce and Aha! It’s victory for you my friend!” In this way, dopamine can help us stay motivated to achieve our goals.
Dopamine, as a chemical reward mechanism, is reinforcing because it encourages you to go after the types of things that felt good in the past, while reminding us to steer clear of undesirable outcomes. Examples of this could include avoiding a food that made you ill, making sure you don’t run out of gas on your way to work, or avoiding certain individuals.
Dopamine is strongly involved with food and sex. It can be the incentive that helps spur the direction of your desires and cravings-such as reminding you of grandma’s eggnog pie motivating you to clean the attic in search of that secret recipe.
A dopamine rush is what your kid was experiencing when he lost track of time playing that video game until 2 in the morning. And your daughter, what does she see in that guy? Has she lost her mind? Or maybe it’s just a little too much dopamine in the ventral tegmental area of her midbrain…ah youth…
Meanwhile, perhaps you’re thinking about the benefits of a promotion, retirement, exotic vacations to your favorite tropical island, or the new house you’ll buy someday when you get out of debt and have more money. In addition, dopamine naturally declines when a novel stimulus becomes highly available, and tends to decrease with age. One can only eat so much ice cream in a day and a game only thrills for so long before the novelty fades, which is usually right around the time the next big thrill arrives on the scene. Humans seem always to be in search of that happy ending- the thing that will bring us a little closer to “happily ever after.” In this way, dopamine can be a wonderful curse.
Stimulants like cocaine and methamphetamine also use the brain’s dopamine reward system, which is one reason they are so addictive-it’s a way of getting an intensely rewarding feeling without having to work for it. Addiction can be viewed as a form of misguided motivation. Unfortunately, this tends to make it more difficult to enjoy lesser everyday pleasures, which feeds into the cycle of addiction and is unsustainable and exhausting for the brain and body.
Dopamine is involved in many other functions as well such as dreaming, mood, working memory and learning, as well as sexual arousal.
Risks of Dopamine Imbalance
Schizophrenia, a splitting of mental functions that affects cognition, emotion, and behaviors causes a variety of attention and memory problems. It is a condition often associated with too much dopamine in the mesolimbic pathway which is part of the ventral tegmental area of the brain. The nucleus accumbens, which is part of the striatum and innervated by dopaminergic fibers from the ventral tegmental area is also implicated. When these areas are destroyed in rats they seem to lose all motivation to work for a reward. In humans, the striatum seems to be where dopamine is associated with desire and pleasure. Additionally, high levels of dopamine in the ventromedial prefrontal cortex may be linked with planning and a willingness to work harder for rewards. In Schizophrenia, there seems to be a loss of dopamine in the prefrontal cortex, an area of the brain involved in strategic problem solving, adaptation, impulse control, attention, and socially adaptive regulation of the expression of intense emotional states.
The mesolimbic pathway furthermore includes the amygdala, hippocampus, and the bed nucleus of the stria terminalis. Schizophrenia can sometimes be treated with drugs to inhibit dopamine production, though one concern is the current lack of drug specialization to reduce dopamine in only the problem areas of the mesolimbic pathway without furthering a deficit in other areas, such as the prefrontal cortex. The best drugs of the future will need to find a way of addressing these chemical imbalances with more precision.
Decrease Latent Inhibition, Increase Creativity?
Now be patient with me on this one because I do not fully understand all of the implications myself, but here goes: latent inhibition is a normal adaptive process which is the learned ability to ignore unimportant information from one’s environment-typically that which previously proved inconsequential, and thus allows the mind to focus on more relevant stimuli. But if you increase dopamine levels in the ventral tegmental area of the brain this is thought to decrease latent inhibition which has, in some cases, been associated with an increase in creativity. So why is this? Perhaps it is because a brain tasked with making sense out of an intense amount of information requires a creative approach to synthesize it all.
A lower density of D2 receptors in the thalamus (responsible for consciousness, sleep and alertness) also seems to be correlated with less information being filtered before moving onto the cerebral cortex. More info on D2 receptors here.
Some brains seem better equipped to handle this information overload than others, and this can sometimes mean the difference between creative genius and mental impairments, like bipolar disorder and schizophrenia. However, dispositional and environmental factors play a key role in this, and the complex interplay of other neurotransmitters like glutamate, acetylcholine, and serotonin are relevant as well but not fully understood.
I’m curious how introverts and extroverts compare and vary in their response to dopamine and conditions of latent inhibition. Could they be affected by informational overload in different ways? And how do we compare internal versus external stimulus and the associated filtering of information which affects our attention and focus? For example, if introverts are more sensitive to the external environment in general, is it because they have decreased latent inhibition (more dopamine and thus more difficulty suppressing irrelevant external stimulus) than extroverts? In which case, perhaps extroverts require more dopamine to feel creative and reduce latent inhibition? Whereas an introvert either needs to increase latent inhibition (tune out irrelevant external details, decrease dopamine) or keep their dopamine levels constant, but have access to a less stimulating environment in which to finish processing all that buzz if things get overwhelming?
I was going to share a story about Einstein’s absentmindedness and forgetting what city he was going to, but according to Snopes that story looks like a fake. Similar concept though to what I am wondering… so would someone like Einstein be really good at latent inhibition, and thus waste less attention on the external world? Or did he have low latent inhibition, and actually take in more from the environment, thus experiencing a different, more creative interpretation of it? Food for thought.
In Parkinson’s Disease, the degenerative impairment of movement seems to be caused by the degeneration of dopamine secreting neurons in the substantia nigra. Levodopa is often prescribed as a dopamine booster.
Attention Deficit Hyperactivity Disorder (ADHD)
Attention Deficit Hyperactivity Disorder (ADHD) makes it difficult to focus and that is associated with a loss of dopamine activity. ADHD can sometimes be treated by increasing the dopamine levels in the brain. Ritalin is a psychostimulant that has been prescribed for this purpose.
Depression can be described as a lack of energy and enthusiasm for life, a gloomy melancholy accompanied by feelings of hopelessness and inadequacy. If depression is due to low dopamine levels, antidepressants may be beneficial in increasing dopamine levels, allowing the brain to experience rewards for the body’s efforts.
DRD4 Dopamine Receptors
The long variation of the DRD4 dopamine receptors are suspected to be linked with sensation and novelty-seeking exploratory risk taking personality types; however there are many other environmental and genetic mediating factors which can drastically tone down the effects.
How to Increase Dopamine?
Dopamine does not cross the blood-brain barrier, so if given as a drug, it would act on the sympathetic nervous system increasing blood pressure and heart rate, but not affecting the central nervous system. In the body, synthesis usually takes place in the medulla of the adrenal glands which also produces epinephrine and norepinephrine.
To increase dopamine in the brain, it must be synthesized in the brain from one of its amino acid precursors.
Dopamine precursors include: L-Phenylalanine, L-Tyrosine, and L-DOPA.
L-Phenylalanine → L-Tyrosine → L-DOPA → Dopamine → Norepinephrine → Epinephrine (adrenaline)
(You can learn more about dopamine’s complete metabolic pathways and coenzymes on wikipedia)
How to Increase Dopamine levels without Drugs
Did you know there are foods that increase dopamine levels? You can easily increase dopamine with L-Tyrosine, a natural dopamine precursor, through your diet. Some good sources of dietary protein containing l-tyrosine include eggs, spirulina, and avocados as well as salmon. Low body temperature and low blood pressure, possible signs of an under-active thyroid, can also indicate a deficiency in l-tyrosine.
How to Increase Dopamine with L-Tyrosine
The brand of L-tyrosine I sometimes take as an occasional supplement recommends taking one 500mg capsule per day with water. Other sources suggest a typical dose is between 500-1000mg of L-Tyrosine 30 minutes before a meal 1-3 times per day. Personally, I have never exceeded 2,000 mg of l-tyrosine in a day and not for more than a day at a time. I find that it is quite energizing and I feel more outgoing and interactive, but individual results will vary with body size, diet, current levels and needs. It is always recommended that you communicate to your health care provider any supplements you wish to take prior to starting as they can offer personalized advice bearing in mind your medical history and health goals.
Risks of Too Much L-Tyrosine
Too much L-Tyrosine could cause nausea, vomiting, anxiety, and diarrhea.
Risks of Too Much Dopamine
Too much dopamine can be problematic because it increases the temptation to be impulsive, takes risks, or seek instant gratification.
Five Simple ways to Increase Dopamine for Memory Benefits
1) Ginkgo Biloba shows great promise as a brain supplement because of its ability to boost dopamine levels, increase oxygen flow to the brain, and improve memory while reducing stress.
2) Enjoy foods rich in antioxidants.
3) Get plenty of sleep as this gives your body a chance to repair and replenish its natural dopamine supply while consolidating the informational patterns you have experienced throughout your day.
4) Take a good B-Complex that includes Vitamin B6, which increases mental clarity. Elderly people with dementia are often deficient in Vitamin B6. It can also help with depression. Do not exceed recommended amounts though as too much could damage the brain and nervous system.
5) Consume a healthy diet. While high calorie high fat meals may temporarily boost dopamine levels, there is often a steep crash afterwards which can lead to exhaustion.
Increase Dopamine Levels with Drugs
Bupropion (Wellbutrin or Zyban) is sometimes prescribed in the treatment of depression because it blocks the reuptake of dopamine and increases dopamine activity in the brain.
Methylphenidate (Ritalin) has been taken to treat ADHD with its associated hyperactivity and impulse control issues. Children with ADHD often have less activity in the mesocortical dopamine system and Ritalin may assist with attention by boosting dopamine levels.
Depression, Addiction & Motivation
There is a tendency for too little dopamine in the striatus and ventromedial prefrontal cortex to be associated with a lack of desire to engage in work, especially work that involves little reward. This lack of motivation has been implicated in ADHD, depression, and schizophrenia. Neuroscientists and postdoctoral student Michael Treadway of Vanderbilt University found in a study that young adults with a tendency to choose the easier, less rewarding button pushing tasks (versus the harder task which offered a greater reward for pushing the button with the pinky finger) actually had higher dopamine sensitivity in their Anterior Insula, which is an area that monitors things like hunger, thirst, cold, and pain. High levels of dopamine in the Anterior Insula may therefore effect what a person focuses on. In this study that seemed to imply the cons rather than the pros of the harder task. Focusing on risks rather than rewards can sometimes be linked to depression.
However, I don’t want to undermine that being cautious can also be advantageous in certain contexts and it is important not to over-generalize. There are legitimate reasons to exert caution in some instances and to weigh the pros and cons by asking questions such as, “In what ways will this reward contribute or detract from the quality of my life?” or “How will I feel looking back on this decision next week? In 2 years?” If it is likely to significantly increase stress with only marginal benefits, for example, choosing the “reward” may not be worth it. However, thoughtful and intentional decision making is clearly not what is going on in the case of a serious dopamine imbalance. If there is a chronic tendency to avoid rewarding challenges, there could be a medical reason for it.
Dopamine is also a factor in sociability, though the brains of introverts and extroverts respond to dopamine in differing ways. More research is required on that subject, however, if we are to appreciate the strengths of both personality styles. If you still want to increase your dopamine levels, I bet a brain scanner is starting to sound pretty useful!