Download The autonomic nervous system

The autonomic nervous system
Stellek Bálint Sándor
2016.10.27.
- The autonomic nervous system (ANS) is a division of the peripheral
nervous system (other division is somatic nervous system)
- It influences the function of internal organs
- It acts largely unconsciously
- It regulates bodily functions such as
heart rate, digestion, urination,
respiratory rate etc.
- Within the brain, the ANS regulated
by the hypothalamus
- The autonomic nervous system is divided into two
part:
- Sympathetic nervous system
- Emerges from the spinal cord in the thoracic
and lumbar areas ("thoracolumbar outflow”)
- Parasympathetic nervous system
- It has “craniosacral outflow”, meaning that
the neurons begin at the cranial nerves and
sacral spinal cord.
Sympathetic nervous system
- It’s primary process is to stimulate the body's
fight-or-flight response
- And it constantly active at a basic level to
maintain homeostasis.
Parasympathetic nervous system
- The parasympathetic nervous system (PSNS) is
the other divisions of the autonomic nervous
system
- The parasympathetic system is responsible for
stimulation of "rest-and-digest" or "feed and
breed” activities.
- These occur when the body is at rest, especially
after eating, including sexual arousal, salivation,
lacrimation (tears), urination, digestion and
defecation.
- It has 3 main division (nerves): Cranial nerves,
vagus nerve and pelvic splanchnic nerves
- Two kinds of neurons involved in the transmission of any signal through the
sympathetic and parasympathetic system: pre-ganglionic and post-ganglionic
- Ganglion is a nerve cell cluster or a group of nerve cell bodies located in the
autonomic nervous system. Ganglia house the cell bodies of afferent nerves.
- In the sympathetic and parasympathetic nervous system, efferent nerve signals
are carried from the central nervous system to their targets by a system of two
neurons.
- The axons of preganglionic parasympathetic neurons are usually long, extending
from the CNS into a ganglion that is either very close to or embedded in their
target organ (sympathetic is the opposite).