Chances are these terms are nothing new to you. Complex chemicals govern mood, pleasure, love, trust, stress, pain, anxiety, and depression, just to name a few. The sheer range of effects these hormones have on the human experience makes a little knowledge go a long way to understanding how we tick.

Before we go any further, it is important to understand that many chemicals in the body (dopamine, serotonin, et cetera.) are used as both neurotransmitters and hormones; the distinction lies in how they are secreted. Hormones are chemical messengers transmitted through the blood to reach target cells and organs; they are part of the endocrine system. On the other hand, when these chemical messengers act as neurotransmitters, they traverse the synaptic cleft (The junction at which synapses communicate), transmitting signals between neurons, glands, or muscle cells.

In layman's terms, hormones are like long-distance messengers using the blood highway, and neurotransmitters are like short-distance messengers jumping across tiny gaps between nerve cells.

This short article only addresses a small part of the ever-growing field of psychology and neuroscience. If you find this field fascinating, there are a range of degrees and qualifications such as a Bachelor of Psychological Science or Graduate Diploma in Psychology which delve into these topics on a deeper level.

Dopamine

Dopamine is often considered the ‘’feel-good’’ hormone. Produced by the adrenal gland, it travels across the four dopaminergic pathways, affecting pleasure, satisfaction, and motivation.

Dopamine plays a vital role in developing reward-seeking behavior. If you measured the dopaminergic output of a monkey as it moved toward a banana tree, you would see a rise in dopamine with each step said monkey made closer to the tree; the second monkey gets what monkey wants, the dopamine output stops, why? Because the reward has been attained. The “reward” in evolutionary terms is whatever a monkey needs to survive. Thus, dopamine is the hormonal drive for a monkey to get what he needs to live.

Dopamine rewards, however, do not always develop healthy reward circuits. They are a motivating factor in addiction, causing that craving feeling addicts feel when they use, driving them to use again to satisfy said craving.

Serotonin

Serotonin is recognized as a key player in mood regulation, sleep cycles, and feelings of happiness. The serotonin system, like dopamine, has its roots in evolutionary biology, serving as a crucial factor in maintaining both survival and well-being.

Notably, about 95% of serotonin originates from gut bacteria, emphasizing the microbiome's role in mental well-being. This gut link has become the focus for many popular supplements such as 5HTP, an amino acid your body can convert into serotonin in the gut.

When serotonin levels are stable, you feel more focused, happier, calmer, and sleep better. Serotonin is needed for the body to produce melatonin, the chemical responsible for sleeping, waking, and energy production.

The delicate balance of serotonin levels is important in managing mental health conditions such as anxiety and depression. This understanding has led to the development of Selective Serotonin Reuptake Inhibitors (SSRIs) as a common form of antidepressant, which is believed to work, as the name suggests, by Inhibiting the reuptake or absorption by nerve cells of ‘used’ serotonin.

Oxytocin

Dubbed the ‘love hormone’, oxytocin is produced in the hypothalamus, the region of the brain where the nervous and endocrine systems meet. It is then released into the bloodstream via the pituitary gland.

One of its primary functions is to facilitate uterine contractions during childbirth, playing a crucial role in the labor process. Oxytocin also promotes the bonding between a mother and her newborn, fostering maternal instincts and emotional connections that are fundamental for the well-being of both mother and child.

When oxytocin isn't helping create new life, it helps us to bond. Recent studies show how partners who express gratitude to one another, both in action and conversation, will produce more oxytocin. The oxytocin bond enhances emotional connections and fosters a sense of intimacy. This neurochemical bond contributes to the overall depth and quality of relationships, promoting a lasting and positive connection between partners.

Endorphins

There are over 20 different types of endorphins, each with different functions. When you feel pain, nerves in your body send signals to the brain, triggering a release of endorphins that block the receptors that would receive said signals. This can be the reason why when you break an arm, the immediate feeling of pain is quickly numbed, allowing you to reach safety before the full effects are felt.

Endorphins are no quasi-painkillers. Binding to the same opioid receptors, Studies show them to be 18 to 33 times stronger than morphine. This speaks to the sheer power of the body to cope.

Don't worry, there are less painful ways to release endorphins than breaking an arm, exercising, eating dark chocolate, and making love all release these happy hormones. The effects of good endorphin levels range from alleviating depression, improving self-esteem, and maintaining a healthy weight to easing stress levels.

Neurotransmitters, hormones, and happiness

As this field rapidly develops through research, it pays to keep up to date. Neurotransmitters were only discovered in 1921, and if you search ‘serotonin’ or ‘dopamine’ on PubMed, there are thousands of results and over a hundred clinical trials in the last year alone.

The more research is done, the better our understanding becomes. This understanding can be a force for good, whether it is developing healthy reward circuits, boosting natural endorphin levels to better cope with stress, or harnessing the power of oxytocin to improve complex relationship bonds.