http://knowingneurons.com/2014/11/05/inhibitory-neurons-keeping-the-brains-traffic-in-check/
Imagine that you’re driving down a road
undeterred, no red lights or stop signs to slow you down. While that may
seem like a very exciting idea, it is obviously very dangerous, since
our roads are not all parallel, but interconnected in a number of
different ways. For traffic to go smoothly in all directions, we have
stop signs, red lights, speed bumps and police cars to make sure no
accidents occur. In much the same way, our brain has a mechanism to keep
the excitation in check. Information in the brain flows via excitatory
neurons that have properties depending on their anatomical location. For
example, a neuron in the visual cortex will respond to visual stimuli,
and a neuron in the auditory cortex will respond to auditory stimuli.
Since excitation cannot go on forever, we have to make sure it slows
down or stops whenever required. This is known as inhibition.
Inhibition is as important as excitation, if not more so. The neurons
that perform this function are known as inhibitory neurons, and they
have the special property of making sure our brain functions smoothly
and is accident-free.
When activated, GABAergic neurons
release the neurotransmitter GABA, which is known to hyperpolarize the
postsynaptic neurons, i.e. it makes the membrane potential more
negative, making it harder for the neuron to reach the threshold to fire
an action potential, thereby causing ‘inhibition’. Most often,
inhibitory neurons are also called GABAergic neurons
for that reason. Although they constitute only 20-25% of all neurons in
the cortex, they are strikingly diverse, with different morphologies,
sizes, intrinsic properties, connectivity patterns, and protein
expression. Based on their molecular properties, a significant effort
has been made in recent years to classify them into subgroups [1]. Let’s
explore a few of the major inhibitory neuron subtypes:
Pictures and more at link that I'm positive your doctor will not be able to describe.
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