Neurotransmitters & Neuromodulation
Just like hormones govern many chemical functions in the body, the brain's chemical functions are
governed by messengers called neurotransmitters. A neurotransmitter is a chemical messenger used by
neurons (nerve cells) to communicate with other neurons.
In neuroscience, neuromodulation is the process in which several classes of neurotransmitters in the nervous
system regulate diverse populations of neurons (one neuron uses different neurotransmitters to connect to
several neurons). As opposed to direct synaptic transmission, in which one presynaptic neuron directly
influences a postsynaptic partner (one neuron reaching one other neuron), neuromodulatory transmitters secreted
by a small group of neurons diffuse through large areas of the nervous system, having an effect on multiple
neurons. Examples of neuromodulators include dopamine, serotonin, acetylcholine, histamine, dopamine and
others.
A neuromodulator is a relatively new concept in the field, and it can be conceptualized as a neurotransmitter
that is not reabsorbed by the pre-synaptic neuron or broken down into a metabolite. Such neuromodulators end
up spending a significant amount of time influencing (or modulating) the overall activity level of the brain
(promoting CHANGE – neuroplasticity). For this reason, some neurotransmitters are also considered as
neuromodulators.
Norepinephrine, also known as noradrenaline, is a neurotransmitter found in the sympathetic nervous system.
The sympathetic nervous system stimulates the heart, blood vessels, sweat glands, the large internal organs, and
the adrenal medulla in the brain. Norepinephrine is released as a neuromodulator when the brain is engaged in
new, novel and/or surprising (interesting) experiences.
Dopamine is widespread in the brain as well as the rest of the nervous system. This neurotransmitter plays a
critical role in the control of movement. It has a stimulating effect on the heart, the circulation, the rate of
metabolism, and is able to mobilize many of the body's energy reserves. It helps to modulate brain activity,
control coordination and movement, and regulate the flow of information to different areas of the brain.
Dopamine is released in the brain when it experiences pleasure, reward or joy and is instrumental in facilitating
the integration of thoughts and feelings.
Acetylcholine triggers the brain to hold on to the memories being formed. The more we focus, the more we
remember. When we focus our attention on a particular task or problem, the nucleus basalis, a deeply-nestled
region of the brain, secretes a substance called acetylcholine. Acetylcholine and Dopamine together stimulate
new neural growth and brain plasticity.
Our thoughts, memories, perceptions, moods and feelings all depend upon neurotransmitters. These are our
brain’s chemical messengers that make moods, memory and mental performance possible. When key
neurotransmitters are low our brain suffers. Our thoughts get cloudy, our focus fuzzy, and our memory forgetful.
Neurotransmitters foster:
 Greater Ability to sustain focus
 Enhanced Mental Clarity
 Better Recall
 An end to brain fog
 and pick up Energy Crashes
The human brain is very capable of automatically manufacturing the quantity of chemicals it needs IF it is given
the raw materials to do so, such as nutrients from the proper foods, physical exercise and challenging cognitive
engagement. Additionally, stress, worry, chemical use, poor nutrition, pollution and other factors of modern
life are known to deplete neurotransmitter levels.
Mosteller, 2010