hit counter

Scientists Identify Part of Brain For Exercise Motivation: Dorsal Medial Habenula

Should you blame your brain if you don’t have the motivation to go to the gym and exercise? A recent discovery published in The Journal of Neuroscience will support those putting blame on their brains. Researchers in this particular study discovered that a tiny region of the brain called the “dorsal medial habenula” may be largely responsible for influencing an individual’s motivation to hit up the gym or remain a couch potato.

In addition to having an influence on our level of motivation to exercise, researchers discovered that the habenula may play a prominent role in mood regulation. Assuming this research is supported by follow-up studies, it could pave the way for development of new treatments that target both depression and obesity.

Region of brain linked to exercise motivation: Dorsal Medial Habenula

What does the dorsal medial habenula do? A healthy functioning dorsal medial habenula is thought to influence mood, motivation (specifically to exercise), as well as improves an animal’s ability to survive in a world filled with danger, risks, and rewards. Dysfunction of the habenula is associated with an increased likelihood of developing depression, schizophrenia, and psychosis.

  • Dopamine: Dopamine is a neurotransmitter that is involved in feelings of pleasure. The habenula has a unique influence on dopamine in the brain. When an animal fails to obtain some sort of reward, the habenula prevents neurons from releasing dopamine. Thus when you experience failure, you do not feel pleasure or a sense of reward.
  • Mood regulation: Scientists have found that the habenula is linked to depression and pessimism. It has been discovered that when the habenula is overactive, we experience an increase of negative thinking and our outlook becomes pessimistic.
  • Motivation: This research supports the idea that the habenula can influence voluntary motivation to exercise. Therefore whether you actually want to go to the gym or remain lazy can largely be influenced by this brain region.
  • Other effects: The habenula is thought to have an influence on levels of anxiety, pain, pleasure, and our sleep cycle.
  • Pleasure: Studies have shown that the habenula can determine whether someone gets pleasure out of rewarding activities vs. experiencing no pleasure from rewarding behaviors.
  • Reward circuit: Activation of the dorsal medial habenula appears to increase ability to experience reward and pleasure associated with that reward. It basically is thought to help generate a positive-feedback loop.
  • Survival: A study conducted back in 2010 demonstrated that the habenula played a pivotal role in helping animals survive in a world filled with dangers, hidden rewards, and other risks. In other words, it is thought to improve decision making to ensure survival when faced with the unknown.

Seattle Children’s Research Institute: Dorsal Medial Habenula Study (2014)

A new study conducted by the Seattle Children’s Research Institute utilized mice to specifically study the dorsal medial habenula. Based off of previous studies, researchers knew that the habenula could play a role in regulating behavior and mood. Lead researcher, Eric Turner used mice that were genetically altered to inhibit signaling from the dorsal medial habenula, and other “normal” mice without inhibited signaling.

Part 1: Habenula inhibited mice vs. Normal mice

Upon comparison of the genetically altered (signal inhibited) mice with the normal non-inhibited mice, the genetically altered mice were extremely lazy. Researchers noted that they acted fatigued, lethargic, and rarely ran on their exercise wheels. The normal mice exhibited typical motivation to run in exercise wheels, something they enjoy doing.

It should also be noted that the habenula-signal-inhibited mice no longer enjoyed drinking sweetened water like the normal group of mice. Although the genetically altered mice were still fully capable of exercise, their preference was clearly to stay lazy; they had no motivation.

Part 2: Choosing habenula stimulation with optogenetics

After comparing the habenula-inhibited mice to the normal mice, Dr. Turner conducted another comparison. They utilized a new laser technology called “optogenetics” to stimulate activity in the dorsal medial habenula. This technology is currently being developed by the Allen Institute for Brain Science, and mice were given the option of activating this area of the brain vs. keeping it inactive.

They were allowed to turn “response” wheels with their paws – one of which increased activity in the dorsal medial habenula, the other which kept functioning the same. The mice demonstrated a strong preference for turning the response wheel that stimulated the dorsal medial habenula. This further supports the idea that this area of the brain is associated with pleasure and rewards.

Although in the past we knew that the habenula influenced a variety of functions, we didn’t have the technology to analyze various sub-regions like the dorsal medial area. It should also be noted that most methods of brain stimulation could not pinpoint this particular area of the brain, only the latest technology such as optogenetics has made this a reality.

Recap of study findings (2014)

  • Habenula-inhibition is linked to lack of motivation
  • Habenula stimulation is associated with motivation, reward, and pleasure
  • Dorsal medial habenula controls desire to exercise (for mice)

Other related notes

  • Habenula structure is similar in mice and humans
  • The habenula’s functions are likely to be similar
  • Habenula-inhibition is associated with less reward and less motivation
  • Habenula stimulation is associated with exercise motivation, reward, and pleasure
  • Could ultimately lead to treatments for depression, fatigue, and obesity

The dorsal medial habenula was found to specifically control the desire to exercise in mice. Although the study was conducted with mice, there are many parallels between the rodent and human brain. In particular, the structure of the habenula in humans is very similar to that found in mice. Furthermore, researchers hypothesize that the function of the habenula is similar throughout all species: to regulate mood and motivation.

It is already known that there are many psychological benefits of exercise, including helping reduce symptoms of depression. Some could go as far as to make the argument that, for certain people, consistent exercise acts as a cure for depression. Many people get depressed because they lack motivation to simply get up and do something physical and in some cases, become overweight.

Should you blame your brain for feeling lazy?

Probably not. Blaming your brain because you feel lazy and/or lack motivation to do something isn’t going to benefit you in any way. In fact, it may encourage you to throw in the towel and essentially give up on making healthy lifestyle changes such as exercising more frequently.  In many cases, people feel lazy, but force themselves to exercise regardless of how they feel.

And in many of these cases, once exercise becomes ingrained as a lifestyle habit, they may actually develop motivation for going to the gym.  Although this is an interesting discovery with some merit, who’s to say that forcing yourself to get exercise (even if you feel lazy) won’t stimulate activity in this area to support future motivation? Additionally it should be noted that this study was conducted on mice and their habenula was genetically altered, most people do not have genetically deficit habenula signaling.

Important things to keep in mind…

Before you assume that your dorsal medial habenula is dysfunctional and the main reason why you can’t motivate yourself to exercise, there are some important things to keep in mind.

  • Habenula-inhibited mice could still exercise: Even the mice with inhibited habenula activity still have full physical capability to workout. If they wanted to exercise, they still could with the same intensity as those with functional habenulas.
  • Study was on mice: Although there are many parallels between the habenula found in mice and that in humans, it is important to keep in mind that the functions may not be identical. Keep in mind that there is not always carryover between effects found in mice and those found in humans.
  • Most people don’t have genetically inhibited habenulas: In this study, scientists used genetically-inhibited habenulas in mice. Most people do not have genetically-altered habenulas with inhibited activity. Therefore, it can be assumed that most people are capable of experiencing adequate activity within the habenula.
  • Not verified in humans: Understand that these results have not yet been replicated among humans. It could be possible that one day scientists will be able to use technology to stimulate the habenula and determine whether added stimulation can increase motivation and voluntary exercise.
  • Blaming your brain: Blaming your brain isn’t going to get anything accomplished, in fact, it may make you more depressed if you assume that you cannot complete certain tasks or will never get into shape because your habenula is abnormal.  In many cases, people like to place blame on something external that cannot be controlled instead of stepping up and making necessary lifestyle changes such as going to the gym more often.

Although I do believe that genetics shape our behavior more than our environment, I do not believe that we have zero willpower. You can choose to go to the gym and exercise just like you can choose to eat a green apple or a red apple. You can decide whether you force yourself to go to work each day or stay home.

Most people aren’t motivated to go to their 9 to 5 jobs, yet they do it for survival. Since exercise isn’t required to stay alive, most people avoid it because it’s really not necessary. What do most people like? Comfortable homeostasis. Throughout the history of humanity, humans may not have liked hunting wild game for food and the hard work it took to build shelter, but they did it anyway to ensure survival.

These days people don’t need to go hunt wild game or build shelter, or be on the lookout for potential predators and competition. Today, all a person needs to do is go to school, get a job, and they’ll have resources to buy food, shelter, etc. Exercise is no longer a survival requirement and since many people don’t feel like working out, they simply don’t work out – because they don’t have to.

It is almost guaranteed that a person would run if they were being chased by a hungry wolf. Motivation is created quickly when faced with competition and fear for safety and survival. Since exercise is no longer a requirement to ensure survival, many people merely blame circumstances on why they are lazy or lack motivation.

In reality, motivation to exercise is not necessarily something that someone is born with, in many cases it is developed through various life experiences. Although I’m sure a highly-stimulated habenula would help a person stay motivated to exercise, it is not a requirement.

How targeting the dorsal medial habenula could be useful

The entire purpose of this study was to determine whether a specific area of the brain may motivate us to exercise. It was thought that discovery of this area of the brain could help develop better treatment options for major depression, and possibly obesity. Lead researcher Professor Eric Turner stated, “Changes in physical activity and the inability to enjoy rewarding or pleasurable experiences are two hallmarks of major depression.”

In the past the brain pathways and regions responsible for determining exercise motivation were not well understood. The ultimate goal for professor Eric Turner and colleagues is to figure out how to manipulate brain activity in the habenula to increase motivation without affecting the rest of the brain.

Treating depression, fatigue, and obesity

Perhaps the most promising aspect of this study is that it could lead to new treatments for depression in a highly demanding market with many poor options. Additionally since stimulation of the dorsal medial habenula may result in improved motivation, increased pleasure, and voluntary exercise, it may be useful for helping treat obesity.

  • Depression: This finding may help researchers develop drugs that stimulate activity in this region of the brain. Additionally, it may help scientists come up with non-pharmaceutical treatment options, possibly utilizing optogenetics technology in humans.
  • Fatigue: In the case of feeling fatigue, there is some evidence to suggest that voluntary exercise would result in improved levels of energy. Additionally if a person is able to stay motivated and get exercise, they are unlikely to be fatigued. Therefore stimulation of the habenula may eventually help with developing treatments for individuals with chronic fatigue.
  • Motivation: It has been found that stimulation of this region can result in increased levels of motivation. The motivation could be beneficial to those who are depressed, and possibly may help treat certain symptoms of ADHD.
  • Obesity (weight loss): Individuals who are obese typically are stuck in a rut and lack the motivation for exercise; thus further reinforcing their obesity. In order to break the unhealthy cycle of being lazy, treatments stimulating this area for motivation will lead to more exercise, and ultimately weight loss.
  • Genetic engineering: In the future, scientists may be able to identify certain genes that are involved in stimulating and/or reducing activity in the dorsal medial habenula. Eventually scientists may be able to use gene therapy or modifications to stimulate efficient activation in this region of the brain.

Note: It would be interesting to see whether various medications such as stimulants and/or an antidepressant like Wellbutrin could influence activity in this area of the brain.

Lead researcher Eric Turner was quoted saying that “working in mental health can be frustrating” in part because not a lot of progress has been made in new treatments. He hopes that more can be learned about how the brain functions to “help people with all kinds of mental illness.” I am in full agreement with Dr. Turner based on the fact that treatments for most mental health conditions may “work” but may not target the actual problem within the brain, they merely change neurotransmitter levels to make us feel better.

This study is an important step in better understanding the specifics of the brain and potential influences that certain regions have upon our behavior. As the title suggests, we now know that little regions like the dorsal medial habenula can have a big influence on our behavior and mood. Feel free to share your thoughts on these findings in the comments section below.

Related Posts:

MHD News (100% Free)

* indicates required

3 thoughts on “Scientists Identify Part of Brain For Exercise Motivation: Dorsal Medial Habenula”

  1. Would the only way to improve the function of someone’s dorsal medial habenula be through medicine or could it be through other lifestyle changes like diet or other supplements and vitamins?

    Reply
    • Hi Wendy, these findings shouldn’t be assumed as 100% true for humans until they are confirmed by future studies. With that said, your thinking is similar to mine… how are we sure that humans with deficient activity in this area wouldn’t benefit just as much from lifestyle changes such as forcing themselves to work out, eat healthy, etc.? My guess is that functioning can be improved by consistent lifestyle habits.

      Reply

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.