The brain’s 100 billion neurons connect the various organs and brain
regions into a complex network of circuits that control specific functions
within the body. Simply speaking, these circuits serve as on/off switches
for the millions of messages and processes carried out on a daily basis.
For example, the perception of danger “turns on” circuits in the brain that
induce a fear response, which may communicate to the body different messages
such as “tense up muscles”, “palms sweat”, “increase heart rate”, and “breathe
faster”.
Neurotransmitters control the on/off switches of the nervous system,
but the concept is not quite that simple. Some neurotransmitters are more
likely to facilitate the transmission of certain messages and are considered
“excitatory”. Likewise, some neurotransmitters are more likely to impede
the transmission of certain messages and are considered “inhibitory”. The
concept of excitatory and inhibitory neurotransmission is central to
understanding and successfully incorporating neurotransmitter assessment and
correction into your practice.
Excitatory neurotransmitters increase the likelihood that a neuron’s
signals are sent. Activation of excitatory neurotransmitter receptor sites
causes a chemical change within the neuron that generates an electrical
message. If sufficiently strong, the message travels through the neuron
to the end of the axon, where it causes the release of neurotransmitters, thus
continuing the signal. From a clinical standpoint, excitatory neurotransmitters
are responsible for providing energy, motivation, mental cognition, and other
activities that require brain and body activity.
On the other hand, inhibitory neurotransmitters decrease the likelihood
that a neuron’s signals are sent. Activation of inhibitory
neurotransmitter receptor sites causes a chemical change within the neuron that
opposes the effects of excitatory receptor activation. From a clinical
standpoint, they are generally responsible for calming the mind and body, inducing
sleep, and filtering out unnecessary excitatory signals.
Neurotransmitters define our moods, actions, and
health. The importance of neurotransmitters transcends their role in the
brain. Organs throughout the body are connected to the brain via a vast
network of neurons. The brain uses neurotransmitters to tell the heart to
beat, the lungs to breathe, and the intestines to digest. This is known
as the autonomic nervous system. Nowhere in nature does there exist
another class of molecules with such importance and biological influence as the
neurotransmitters. To reiterate, basic knowledge of the excitatory vs.
inhibitory concept of neurotransmission is key to understanding the nervous
system. A balance between the levels of inhibitory and excitatory neurotransmitters
is necessary for optimal health. The list of clinical problems associated with
neurotransmitters is long and continues to grow as researchers establish
important links between the scientific and clinical effects of
neurotransmitters. Some of the most significant clinical issues linked
to neurotransmitter imbalances are: anxiousness, appetite control,
attention issues, developmental delays, behavioral problems, low mood, fatigue,
libido, women's issues, headaches, mood disorders, sleep disorders, weight
issues, and many more. Testing is available for these and other conditions.
A balanced nervous system is necessary to maintain
optimal health. When the critical balance between the excitatory and
inhibitory systems is lost, it creates a situation that increases the
likelihood of a neurotransmitter-related condition developing. A
healthy nervous system is characterized by meeting two basic criteria.
Number one, it must have sufficient supplies of the necessary
neurotransmitters. Secondly, the excitatory and inhibitory systems must
work together in a manner that delivers signals appropriately. The second
criterion is quite dependent upon the first, in that the supply of
neurotransmitters primarily dictates excitatory/inhibitory balance. Many
neurotransmitter-related conditions are believed to be the result of
insufficient neurotransmitter supplies.
The fear response in humans is controlled in an area of the brain called the amygdala. An individual who visually interprets a somewhat stressful, but non-threatening situation sends an excitatory neurotransmitter signal from the eyes to the amygdala. If this individual has a healthy nervous system, inhibitory neurotransmitters will filter out the excitatory message, thereby preventing an unnecessary fearful response to the non-threatening situation. If the individual has a compromised inhibitory system, the excitatory stimulus will override the weak inhibitory message, thereby activating an unnecessary fear response.
From Neuroscience