Download Classifications of Neurons 1. Function 2. Structure 3. Shape

Anatomy
of the
Nervous System
I. Cells
Four functions of neurons
1. Receive and integrate inputs
dendrites, soma
2. Generate a nerve impulse (action potential)
axon hillock
3. Conduct the action potential
axon
4. Transmit information to target cell
(neuron, muscle, gland)
nerve terminals
Dendrites and cell body
Receive and integrate
inputs
Axon hillock and
initial segment
Generate action
potentials
Axon
Conducts action
potential
Terminals
Synaptic transmission
receives and integrates inputs
Axon hillock
Generates action
potential
Conducts action potential
Transmit to
target cell
Classifications of Neurons
1. Function
2. Structure
3. Shape
4. Effect
5. Axon length
6. Neurochemical identity
Classifications of Neurons
1. Function
a. sensory neurons
b. motoneurons
c. interneurons
Classifications of Neurons
1. Function
2. Structure
a. unipolar
b. bipolar
c. multipolar
A
B
100μm
Classifications of Neurons
1. Function
2. Structure
3. Shape
e.g., pyramidal, stellate, basket, granule,
etc.
Classifications of Neurons
1. Function
2. Structure
3. Shape
4. Effect
a. excitatory neurons
b. inhibitory neurons
Classifications of Neurons
1. Function
2. Structure
3. Shape
4. Effect
5. Axon length
a. projection neurons (Golgi Type I)
b. local neurons (Golgi Type II)
Classifications of Neurons
1. Function
2. Structure
3. Shape
4. Effect
5. Axon length
6. Neurochemical identity
e.g., cholinergic, dopaminergic,
GABAergic, etc.
Classifications of Neurons
1. Function
2. Structure
3. Shape
4. Effect
5. Axon length
6. Neurochemical identity
Types of glial cells
1. Astrocytes
2. Microglia
3. Oligodendroglia
4. Schwann cells
Types of glial cells
1. Astrocytes
a. mechanical support
b. metabolic
support
transport nutrients and wastes
c. encapsulate synapses
d. regulate chemical and ionic environment
e. form scar tissue
f. act as phagocytes
Types of glial cells
1. Astrocytes
2. Microglia
a. act as phagocytes
b. part of brain’s immune system
Types of glial cells
1. Astrocytes
2. Microglia
3. Oligodendroglia
myelinate axons of central nervous system
Types of glial cells
1. Astrocytes
2. Microglia
3. Oligodendroglia
4. Schwann cells
myelinate axons of peripheral nervous system
II. Gross
Anatomy
Directional Terms
Rostral
toward the nose
Caudal
toward the tail
Dorsal
toward the back
Ventral
toward the belly
Medial
toward the midline
Lateral
away from the midline
Proximal
near a point of reference
Distal
distant from a point of reference
Directional Terms
Afferent
projecting toward
Efferent
projecting away from
Ipsilateral
on the same side
Contralateral
on the opposite side
Planes of Section
Coronal or frontal
perpendicular to the neuraxis
perpendicular to ground
apply only to brain
Sagittal
parallel to neuraxis
perpendicular to ground
midsagittal = axis of symmetry
Horizontal
parallel to ground
parallel to neuraxis
applies only to brain
Transverse
perpendicular to neuraxis
applies to brain and spinal cord
Oblique
any section not in a standard plane
(intermediate gray)
A. Cervical spinal cord
B. Thoracic spinal cord
C. Lumbar spinal cord
D. Lumbo-sacral spinal cord
Autonomic Nervous System (ANS)
Sympathetic division (arousal)
Parasympathetic division (maintenance)
Prosencephalon = diencephalon + telencephalon
Mesencephalon = tegmentum + tectum
Rhombencephalon =
metencephalon (pons, + cerebellum)
+ myelencephalon (medulla)
SYSTEM NERVORUM CENTRALE
(Central nervous system)
I. ENCEPHALON (brain)
A. PROSENCEPHALON (forebrain)
1. TELENCEPHALON (endbrain; limbic system, basal ganglia & cerebral cortex)
2. DIENCEPHALON (between-brain, or interbrain; hypothalamus & thalamus)
B. MESENCEPHALON (midbrain; tectum & tegmentum)
C. RHOMBENCEPHALON (hindbrain)
1. METENCEPHALON (pons & cerebellum)
2. MYELENCEPHALON (medulla oblongata)
II. MEDULLA SPINALIS (spinal cord)
Notes: "BRAINSTEM" is an imprecisely defined term which usually refers to the rhombencephalon
and mesencephalon together. It may or may not include the cerebellum, and sometimes the
diencephalon is included. "CEREBRUM" or "CEREBRAL HEMISHPHERES" refer to the
telencephalon.