Download CNS Brain * Cerebrum * Cerebellum * Brain Stem * Diencephalon

J.C.C.
THE NERVOUS SYSTEM STRUCTURE SIMPLIFIED
CNS
Brain
* Cerebrum
* Cerebellum
* Brain Stem
* Diencephalon
* Thalamus
* Hypothalamus
* Limbic System
Spinal Cord
* Interneuron
Cerebral Spinal Fluid
PNS
Nervous
Somatic (Voluntary)
Cell
* CNS to Muscle &
* Neurons
Skin
* Glial
Autonomic (Involuntary)
Communication
* CNS to Visceral
* Acton Potential
Organs
* Synapses
* Sympathetic (Fast)
* Parasympathetic (Slow)
Motor Neuron (Efferent)
Sensory Neuron (Afferent)
PERIPHERAL NERVOUS SYSTEM PATHWAYS
FUNCTIONALITY OF THE NERVOUS SYSTEM
CHARACTERISTIC
FUNCTION(S)
Cerebral Spinal Fluid
Shock absorber for CNS protection
Cerebrum
Speech, sensation, communication, memory, reasoning,
will and emotions
Cerebellum
Maintains body balance, coordinates voluntary muscles,
makes muscular movements graceful and smooth
Midbrain
Eye and facial movements
Medulla Oblongata
Regulates respiration and heart beat
Hypothalamus
Integration & command center for autonomic (visceral)
functions; involved in emotions
Brainstem
Contains major ANS reflex centers
Spinal cord
Contains ANS reflex centers for defecation, urination,
erection and ejaculation; extends from medulla
Oblongata to L1; consists of 31 segments; pathway for
nerve impulses to and from the brain
* Memory
* Learning
*Semantic memory
* Episodic memory
* Skill memory
Hold thought; recall past events
Retain & utilize past memory
Numbers & words (language is dependent on this)
Persons & events
Perform motor activity
J.C.C.
VOLTAGE GATED CHANNELS
Sodium (Na+)
Potassium (K+)
* Activation gate – Positive feedback
* Single gate – Negative feedback
* Inactivation gate – volt & time dep.
Refractory Period
Axon Diameter
Myelination
CHARACTERISTIC
Neurons
Glial (neuroglia)
* Oligodendrocytes
* Schwann Cells
FACTORS AFFECTING PROPAGATION
Unidirectional
Larger (less resistance, faster);
Smaller (more resistance, slower)
Saltatory conduction = Faster propagation (in nodes)
THE NERVOUS SYSTEM CELLS
FUNCTION(S)
Electrochemical via synapses
Homeostasis, Supports, Protects, Repairs*, Modulates
neurotransmission,
Forms - blood brain barrier, CSF, Myelin sheath
CNS – no neurilemma = no repair
PNS – yes neurilemma = yes repair