How Many Chemicals Are In The Brain?

This article focuses on answering the question of how many chemicals are in the brain. It will elaborate on the explanation of each of these chemicals and their functions. 

The brain consists of brain cells called neurons that are responsible for processing and transmitting information in the brain, and from the body to the brain and vice versa. In order to communicate with each other, neurons in the brain use electrical as well as chemicals known as ions. Ions are electrically charged particles that enable neurons to communicate with each other. 

These neurons communicate with each other by producing brain chemicals. These brain chemicals are called neurotransmitters. There are several types of neurotransmitters such as; dopamine, serotonin, norepinephrine, etc. 

Neurons are thus said to have electrochemical signs consisting of both electrical and chemical charges. These charges change on the basis of whether the neuron is on rest or is active. When the neuron is active, it is either sending a message or receiving it (Furber, 2012). 

Neurons consist of fluids inside them that contain ions. These ions either have a positive or a negative charge. When at rest, the neuron consists of more negative ions on the inside and positive ions on the outside.

This gives its membrane a negative charge. Whenever there is a signal of brain activity, positive ions rush through the channels into the neuronal membrane. When the charge is strong enough, it starts sending signals to nearby neurons to communicate with them. 

How Many Chemicals Are In The Brain?

Scientists have detected that the human brain has more than 60 neurotransmitters. Most experts also assert that many neurotransmitters are yet to be discovered. These neurotransmitters are the most responsible for the transmission of messages. They also play a role in human cognition and behaviour. 

Types of Neurotransmitters

Neurotransmitters can be categorised into two types: small-molecule transmitters and neuropeptides. 

There is the difference between the two is that small-molecule transmitters such as dopamine and glutamate generally have direct access to act on their neighbouring cells. Neuropeptides consist of smaller molecules such as insulin and oxytocin. These work in subtle ways and regulate the communication of cells at the synapse. 

More often than not, the way neurotransmitters are talked about, it seems as if they have only one function. For instance, dopamine is given the role of being the pleasure chemical, while GABA is considered to be involved only in learning. 

However, as time passes, neuroscientists are discovering newer and more multifaceted functions of neurotransmitters. They are trying to study how neurotransmitters work for and against each other, and how they send neural signals to the cortex. Below we will discuss some of the most studied and well-understood neurotransmitters.


The first neurotransmitter to ever be discovered was Acetylcholine (Ach). Ach is said to be a small-molecule neurotransmitter which involves muscles, and it helps us to convert our intentions into actions. Ach is passed from the neurons into the fibre of the muscle. Ach also plays a role in directing attention, and facilitating neuroplasticity in the brain, especially across the cortex.


Dopamine is one of the most-studied neurotransmitters. This is because dopamine has links to various kinds of human behaviour which includes motivation, and pleasure-seeking, and it plays a role in addiction behaviours. Dopamine also has a role in attention, memory formation, learning, movement, as well as our ability to anticipate pleasure. 

Even though dopamine is widespread in the animal kingdom, high levels of it in humans are what make us unique. This high level of dopamine in humans contributes to our high levels of intelligence, as well as allows us to exist and form complex social interactions and circles. It helps us use language, and assists us in planning and setting goals.

Dopamine is so important for humans that its dysregulation can cause diseases such as Parkinson’s disease, which is caused by the increasing death of dopamine-producing cells in the brain.

Dopamine is created by relatively few numbers of neurons. These are located in the hippocampus, also known as the memory centre of the brain, and the amygdala, which is known as the fear centre of the brain. Dopamine is used by kidneys, pancreas, and immune cells. Thus, its use is also in systems outside the central nervous system (CNS).

Dopamine is also known as our motivation molecule. It produces the feeling of “I did it!” when you complete a task you wanted to accomplish. It also facilitates competitive juices and gives you the thrill to achieve and stand out in all aspects of life – school, career, and social life. 

Dopamine is responsible for and in charge of the pleasure-reward system. It produces feelings of bliss, pleasure, and sometimes even euphoria. If there is too little dopamine produced by the brain it can cause a lack of motivation, and lethargy, and can lead to a lack of focus. 

Dopamine is critical to motivating us, studies have found that dopamine-deficient lab rats lack the motivation to eat or even move! Without dopamine, they choose to starve even in conditions where food is readily available.

Common symptoms of lack of dopamine are discussed in the article above. Some common symptoms of lack of serotonin include; decreased energy levels, sad moods, lethargy, feelings of hopelessness, difficulty sleeping or sleeping too much, cravings for carbohydrates, low sex drive, gastrointestinal problems, as well as engaging in compulsive behaviours.

The symptoms of high dopamine levels include; mania, excess energy, anxiety, as well as increased irritability. Varying levels of dopamine also play a role in the causation of schizophrenia, addiction disorders, as well as attention-deficit hyperactivity disorder (ADHD).


Glutamate (GLU) is known as the most excitatory neurotransmitter in the cortex. Too much glutamate can be detrimental to the person, as it can lead to excitotoxicity. Sometimes, excess release of glutamate can cause the death of neurons as it leads to strokes, traumatic brain injury, or amyotrophic lateral sclerosis. It can also cause Lou Gehrig’s disease, which is a neurodegenerative disorder.

However, the excitement glutamate causes in the brain is also useful in various functions, including learning and memory. The long-term potentiation (LTP) occurs in glutamatergic neurons located in the hippocampus and cortex. LTP is the molecular process which enables the formation of memories. 


The calming chemical, serotonin (5HT) affects mood modulation. A lack of serotonin has been associated with depression, as well as other psychiatric disorders. Serotonin also helps in the management of appetite, sleep, memory, as well as decision-making.

Low levels of serotonin and dopamine cause similar symptoms. However, one stark difference is that dopamine deficiency affects muscles, while serotonin deficiency does not. 


Norepinephrine (NE) is a hormone as well as a neurotransmitter. It is also known as noradrenaline. Norepinephrine affects moods, arousal, vigilance, memory, and stress. Researchers are now focusing on whether norepinephrine plays a role in post-traumatic stress disorder (PTSD) as well as Parkinson’s disease. 

Gamma-Aminobutyric acid (GABA)

Gamma-Aminobutyric acid (GABA) is the antithesis of glutamate, where it is the most inhibitory neurotransmitter. GABA’S function is to inhibit neural signalling. However, if it over-inhibits cells too much, the results of this can be detrimental. It can lead to epileptic seizures and other problems. GABA plays an important role in laying down important neural circuits in childhood, during early development. GABA is known to be the “learning chemical” because it plays a crucial role in deciding whether learning has successfully taken place or not. 


This article focused on answering the question of how many chemicals are in the brain. It elaborates on the explanation of each of these chemicals and their functions. 

Frequently Asked Questions: How Many Chemicals Are In The Brain? 

What is the most common chemical in the brain?

Glutamate is the most common chemical in the brain. It is an excitatory neurotransmitter which is found across the brain and spinal cord. Its functions include early brain development, thinking, memory, and learning. 

What are brains made up of?

Soft tissue, including the grey matter, white matter, nerve cells, and non-neuronal cells make up the brain. The brain also includes small blood vessels. Brains also have high water content and nearly 60% of fat.

Can dopamine and serotonin improve your mood?

It is usually serotonin that plays a role in regulating moods and causing happy moods. Dopamine does not regulate moods but plays a role in stimulation, and memory, as well as helping us stay focused.


Furber, S. (2012). To build a brain. IEEE spectrum, 49(8), 44-49.