Page 10 - SELF-PACED LEARNING MODULES

The parasympathetic The PNS is called the
nervous system (PNS) “feed and breed”
a) Craniosacral flow system.
b) Ach is the NT The PNS exerts a
c) Ach is inactivated calming effect on the
by body; is operative
acetilcholinsterase especially during
d) oculomotor, facial, periods of feeding and
glossopharyngeal, breeding.
and vagus nerves
are PSN nerves
e) Ganglia located
close to the effector
organ
“Paradoxical Fear” This is s a response to
feelings of helplessness
and hopelessness.
Intense firing of the
PNS causes severe
bradycardia and life-
threatening cardiac
rhythm disturbances

Effects of the SNS “The lungs and the
bronchial tubes are
widend to give us more
oxygen.
The motility in the
intestine is reduced - we
shall not digest food - we
must fight or run away!
Blood is sent to the brain
while skin and internal
organs get less.
Muscular tension is
increased.
Heart rate and force is
increased”
SNS PNS
Heart Increased heart rate Lowers HR and force of contraction
and force of
contraction

Eyes Pupil dilation Pupil constriction