Functional Neuroanatomy

1
Functional Neuroanatomy

• Histology
• Neurons and Glial Cells
• Brain Cell Structure and Categorization
• Synapse Function
• Axonal Transport
• Information Flow
• Glial Types and Functions

2
Histological Techniques

• Golgi Stain
• Nissl Stain
• Immunocytochemistry
• Track-tracing (horseradish peroxidase)

3
Neurons and Glials

• Brain Cells 2 types
• Characterization
• Shape
• Size
• Function
• Organization

4
Neuron Components

• Dendrites
• Soma
• Axon Hillock
• Axon
• Terminal Button(s) (Bouton)

5
Neuron Characterization

• Shape
• Unipolar
• Bipolar
• Multipolar
• Size
• Large
• Small
• Function
• Sensory
• Motor
• Interneuron

6
Neuron Shape

• Monopolar
• Single shoot off soma
• shoot becomes dendrite axon
• Most common in invertebrates
• Sensory neurons in vertebrates
• Bipolar
• Two shoots off soma
• Found in olfactory system
• Mutipolar
• Most common in vertebrates
• Typically a single axon / multiple dendrites

7
Neuron Size

• Outer layer of the brain cerebral cortex has 6
  layers of cells cerebellum also has layers
• Large cells are in layer IV
• Pyramidal
• In the cerebellum Purkinje, Golgi type I
• Small cells
• Stellate
• In the cerebellum granule, Golgi type II

8
Neuron Function

• Sensory
• Afferent takes external stimulus towards
  central nervous system (CNS)
• Motor
• Efferent takes response away from CNS
• Interneuron
• Connects sensory to motor neurons to elicit a
  response to the stimulus

9
Basis of the Synapse

• Pre-synaptic Zone
• Post-synaptic zone
• Synaptic Cleft
• Synaptic Vesicles
• Dendritic Spines (size number can be altered)
• Receptors

10
Axonal Transport

• Afferents (toward area) / efferents (away from
  area)
• Saltatory Transport (along microtubules,
  neurofilaments microfilaments)
• Anterograde
• Retrograde
• Horseradish peroxidase (HRP) technique
• Neurotoxin injection

11
Glial Function

• Blood brain barrier (BBB)
• Support (astrocytes)
• Nutritive role
• Facilitate transduction (myelin)
• Oligodendrocytes
• Schwann cells
• Neurogenesis
• Electrolyte balance
• Removal of debris (microglial)

12
Glial Types

• Astrocytes
• Microglials
• Oligodendrocytes
• Nodes of Ranvier
• Schwann Cells
• Nodes of Ranvier

myelin-producing
13
Take Home Message

• Neurons
• Shape
• Size
• Function
• Neuronal Communication
• Synapse
• Axonal transport
• Glials
• Types and function