Transcript Nervous System

Classification of the
Nervous System
Central
nervous
system
(CNS)
Brain
(Input to CNS
from periphery)
(Output from CNS
to periphery)
Peripheral
nervous
system
(PNS)
Afferent
division
Sensory
stimuli
Spinal
cord
Visceral
stimuli
Efferent
division
Somatic
nervous system
Motor
neurons
Autonomic
nervous system
Sympathetic
nervous system
Parasympathetic
nervous system
Smooth muscle
Cardiac muscle
Glands
Effector organs
(made up of muscle
and gland tissue)
Skeletal
muscle
Classification
We can divide the nervous system
using many different sets of
terminology…
Anatomical
Direction of Impulses
Functional
Lets just keep it simple…
Central Nervous System
Peripheral Nervous System
Stimulus
NS
Response
Input
NS
Output
More complex features of the NS:
intellect, consciousness, emotions, motivation, association, memory, language …….
Functions of the Nervous System
1. Sensory input – gathering information
 To monitor changes occurring inside and
outside the body (changes = stimuli)
2. Integration –
 to process and interpret sensory input
and decide if action is needed.
3. Motor output
 A response to integrated stimuli
 The response activates muscles or glands
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 7.1a
Structural Classification of the
Nervous System
 Central nervous system (CNS)
 Brain
 Spinal cord
 Peripheral nervous system (PNS)
 Nerve outside the brain and spinal cord
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 7.2
Functional Classification of the
Peripheral Nervous System
 Sensory (afferent) division
 Nerve fibers that carry information to the
central nervous system
Figure 7.1
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 7.3a
Functional Classification of the
Peripheral Nervous System
 Motor (efferent) division
 Nerve fibers that carry impulses away from
the central nervous system
Figure 7.1
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 7.3b
Functional Classification of the
Peripheral Nervous System
 Motor (efferent) division
 Two subdivisions
 Somatic nervous system = voluntary
 Autonomic nervous system = involuntary
Figure 7.1
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 7.3c
Organization of the Nervous
System
Figure 7.2
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 7.4
Central Nervous System:
Central Nervous System:
Consists of
Brain
Located in cranial vault
of skull
Spinal cord
Located in vertebral
canal
Brain and spinal cord
Continuous with each
other at foramen
magnum
Peripheral Nervous System:
comprises peripheral nerves (cranial & spinal)
& ganglia
Two subcategories
Sensory or afferent
(input)
Motor or efferent
(output)
Divisions
Somatic nervous
system
Autonomic nervous
system (ANS)
Sympathetic
Parasympatheti
c
Enteric
PNS
Cranial
Nerves
PNS
Spinal
Nerves
Ganglia