Chemical Agents of Opportunity for Terrorism: TICs & TIMs

Chemical Agents of Opportunity for Terrorism
Training Support Package
Participant Guide
Slide 4
Chemical Agents of Opportunity for Terrorism:
TICs & TIMs
The Balance of the Brain
• The brain is a fine balance of excitatory and inhibitory
influences
– Slight alterations in either direction are significant
Excitation
Glutamate
Catecholamines
Inhibition
Gamma-aminobutyric acid
(GABA)
Module Two - The Clinical Neurotoxicology of Chemical Terrorism
4
The normal state of the brain is maintained by balancing both excitation and inhibition,
each mediated by a unique set of chemicals called neurotransmitters. We alter our
neurotransmitters under normal conditions to suit our needs. For example, in order to
sleep, you need to increase inhibition and reduce excitation.
Neurotransmitters are chemicals in the nervous system including the brain that transmit
information from one neuron to the next (neurons are cells found in the nervous system
and brain). There are a number of different types of neurotransmitters. These include
adrenaline also known as epinephrine which belongs to the neurotransmitter class
known as catecholamines. Some neurotransmitters cause stimulation and others cause
inhibition or sedation. Catecholamines cause stimulation. Another neurotransmitter
that causes stimulation is glutamate. An example of a neurotransmitter that causes
inhibition is gamma-aminobutryic acid. This long chemical name is often abbreviated as
GABA.
The see-saw in the slide represents the delicate balance in the brain between excitation
and inhibition. A person with a normal mental status is someone for whom these
influences are in balance, while disorders are characterized by a tilt in favor of too much
excitation (or too little inhibition) or too much inhibition.(or too little excitation).
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