Brain Regions And Neuronal Pathways
Certain parts of the brain govern
specific functions. Such as the sensory, motor and visual
cortex.
The cerebellum controls coordination and
the hippocampus controls memory.
Nerve cells or neurons connect one area
to another via pathways to send and integrate information.
The distances that neurons extend can be short or long.
For example the reward pathway. This
pathway is activated when a person receives positive
reinforcement for certain behaviors (reward). This happens
when a person takes an addictive drug.
As another example, the thalamus, this
structure receives information about pain coming from the
body, and passes the information up to the cortex.
Pathway For Sensation Of Pain And Reaction To Pain
This is a long pathway, in which neurons
make connections in both the brain and the spinal cord.
Sensation Of Pain And Reaction To Pain
What happens when one slams a door on
one's finger? First, nerve endings in the finger sense the
injury to the finger (sensory neurons) and they send
impulses along axons to the spinal cord.
The incoming axons form a synapse with
neurons that project up to the brain.
The neurons that travel up the spinal
cord then form synapses with neurons in the thalamus, which
is a part of the midbrain (magenta circle).
The thalamus organizes this information
and sends it to the sensory cortex (blue), which interprets
the information as pain and directs the nearby motor cortex
(orange) to send information back to the thalamus (green
pathway).
Again, the thalamus organizes this
incoming information and sends signals down the spinal cord,
which direct motor neurons to the finger and other parts of
the body to react to the pain.
With permission re-published from the
The
Concise Columbia Electronic Encyclopedia ©
Columbia University Press.
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