The central nervous system is able to take in sensory information all around you, interpret that information, and potentially instruct the release of hormones to respond to that information. Certain parts of the brain also instruct the release of hormones in response to what’s going on inside the body.
Our central nervous systems are a big part of why our hormones make their way through the body, but hormones are actually a part of the endocrine system. The endocrine system runs throughout the body but travels in different ways than the central nervous system.
Only certain endocrine functions take place through the brain. As we explore these functions, you will see just how much the different systems of our body need to work together to keep us alive and healthy!
Which Endocrine Functions Take Place in the Brain?
The endocrine system is made up of glands throughout the body, including the brain. The hypothalamus, pituitary gland, and pineal gland are part of this system and are located in the brain. They carry out a variety of functions.
What Is the Endocrine System?
Need a refresher? The endocrine system takes information from the brain and body and responds by releasing hormones from glands. The hormones travel through the bloodstream until they reach their target organs.
The endocrine system has an influence over a lot:
- Homeostasis
- Metabolism
- Mood
- Growth
- Immune response
- Energy levels
- Reproduction
…and more.
All of these functions are the result of hormones being released from glands:
- Adrenal glands
- Hypothalamus
- Kidneys
- Ovaries
- Pancreas
- Parathyroid glands
- Pineal gland
- Pituitary gland
- Placenta
- Thyroid gland
Example of the Endocrine System at Work
The adrenal glands sit on top of each kidney. This gland secretes a few different hormones, including aldosterone. When the body detects low blood pressure, the adrenal gland produces this hormone and sends it to work. Aldosterone regulates sodium, potassium, and water in the body, keeping levels balanced. When it does its job, blood pressure rises back to a healthy level and potassium levels are lowered to a healthy level.
We rarely have to worry about our aldosterone production unless too much of it is being released. The same idea applies to most hormones within the endocrine system. If we stay healthy and the endocrine system does its job, we will remain in good shape!
What Does The Hypothalamus Do?
If you have done any reading or research on the hypothalamus, you know that it keeps the body in check. That’s because it is essentially the “command center” for the endocrine system! The hypothalamus is where the endocrine system and central nervous system meet.
Homeostasis and Fight-or-Flight Response
Most people know the hypothalamus for its control over homeostasis. Our bodies need to be balanced in order to function. Internal temperature, mood, hunger, and hydration all play into homeostasis. If something is off-balance, the hypothalamus must respond accordingly.
Another function of the hypothalamus is the fight-or-flight response. When the hypothalamus receives a signal from the amygdala that the body is in danger, it does two things. It releases a corticotropin-releasing hormone to the pituitary gland and sends a message to the adrenal glands to release other hormones. The hypothalamus may not release adrenaline straight from the brain, but its messaging leads to the release of adrenaline and the resulting side effects.
Production and Release of Hormones
Although the hypothalamus communicates with other glands to maintain homeostasis, it also produces its own hormones! The hypothalamus produces:
- Antidiuretic hormone (regulates water)
- Oxytocin (causes contractions, controls bleeding, also produced when you experience various forms of pleasant physical touch)
- Growth hormone (regulates growth during sleep)
- Prolactin (causes milk production)
- Corticotropin-releasing hormone (response to stress)
- Dopamine (pain prevention, motivation, insulin production, among many other functions)
- Somatostatin (causes the production of other hormones)
- Thyrotropin-releasing hormone (regulates the thyroid gland)
This is just a basic overview of what these hormones do. It is important to note that some hormones, like somatostatin, are released to produce other hormones. When hormones operate in this type of chain reaction, it is called a cascade.
What Does the Pituitary Gland Do?
When it comes to releasing hormones, the pituitary gland is the top dog. Many hormones throughout the body can be traced back to the pituitary gland. This gland works closely with the hypothalamus - it actually hangs right off it! This allows the pituitary gland to receive some hormones produced by the hypothalamus, like oxytocin and antidiuretic hormone. While the posterior lobe of the pituitary gland only releases hormones, the anterior lobe can also produce them.
Here’s one example of how the pituitary gland works with your body. You learned earlier that the corticotropin-releasing hormone (CRH) is produced by the hypothalamus. This hormone goes through the anterior pituitary gland and is released into the body. From there, CRH influences the production and release of beta-endorphin. If you have ever seen Legally Blonde or have experienced a “runner’s high,” you know the importance of beta-endorphins.
When beta-endorphins are released, the body is able to reduce stress and pain. Releasing beta-endorphins also results in “reward effects.” A “runner’s high” occurs when endorphins are released into the body and the runner feels a sense of elation. This feeling doesn’t happen automatically when you run, because it takes time for the body to sense that it needs to release endorphins, produce and release the endorphins, and let them travel through the bloodstream.
What Does the Pineal Gland Do?
Not a whole lot is known about the pineal gland, but we do know that it is the center for melatonin production. You probably know melatonin as a “sleep aid.” People often take melatonin supplements if they have trouble sleeping. In reality, we produce our own melatonin. No supplements needed!
Here’s what happens. Our bodies run on an internal clock known as the circadian rhythm. The circadian rhythm responds to light to keep us awake or prepare us for sleep. How does it do that? Through the release of hormones.
Once your body has established that the sun is down and you are surrounded by darkness, the pineal gland gets the go-ahead to secrete melatonin. Once melatonin is released, the body knows it's time to wind down and get ready for the first stages of the sleep cycle. This process doesn’t happen immediately; melatonin might be released two hours before you actually end up going to sleep.
Want to encourage your body to release melatonin? It’s easy. Just avoid looking directly into the light. Our eyes cannot distinguish the difference between sunlight and a phone screen. Put away screens. Opt for a paperback book and dim lighting. Your body will take care of the rest.
We Rely So Much On Our Brains and Endocrine Functions!
Melatonin production, the release of endorphins, and a shortlist of hormones produced by the hypothalamus just begin to tell the story of how our brains and the endocrine system work together. Scientists have so far identified over 50 different hormones that travel through the bloodstream and help our bodies function. Our brains may not be directly involved with the localized production and release of all these hormones, but they do a lot of work to influence their movement and produce many themselves.
