Overview of Nervous System Flashcards
What are the 5 functions of the CNS?
- Sensation
- Movement
- Thinking
- Experience of emotion
- Autonomic regulation
What is the difference between sensation and perception?
Sensation is the raw data, and perception is the interpretation of the raw data after sensory integration.
What is the difference between white matter and gray matter?
White- myelinated, inner brain.
Gray- unmyelinated, outer six layers
What is a cortex?
Outer layer
What are nuclei?
Clusters of cell bodies
What are columns?
Groups of cell bodies with a similar function organized in a longitudinal fashion.
What is a neuron?
Elementary signaling element of the nervous system.
What is the neuron doctrine?
That the elementary signaling element of the nervous system is the neuron.
What does it mean to say that something has an excitable membrane?
It can propagate an action potential
Define: Temporal summation.
A high frequency of action potentials in the presynaptic neuron results in postsynaptic potentials that overlap and summate.
Define: Spatial summation.
Summation of potentials from different areas of input.
Define: Unipolar cell
A neuron with only one dendrite.
Define: Bipolar cell
Specialized neuron with two extensions, act as SENSORY structures for the retina and olfactory system.
Define: Pseudopolar cell
Dorsal root ganglion in humans. Neuron with two axons: one to the periphery and one to the spinal cord.
Define: Multipolar cell
Most common. Multiple dendrites from cell body with one axon. Many subtypes (pyramidal, granule, Purkinje, basket).
What is anterograde axonal transport?
From cell body to the axon terminal.
What is retrograde axonal transport?
From the axon terminal to the cell body.
What is/and is the function of the blood-brain barrier?
Prevents chemicals that may mess with brain tissue from entering brain. If these things got in, they could cause unwanted action potentials.
What makes up the midbrain?
Tectum + Tegmentum
What makes up the hindbrain?
Medulla oblongata, Pons, Cerebellum
Define: telencephalon
Cerebral hemispheres (cortex+white matter+basal ganglia)
Define: Diencephalon
Thalamus + Hypothalamus + Pineal Body
Define: Forebrain
Telencephalon and diencephalon
Define: rostral
near the front end of the body
What is another name for the midbrain?
Mesencephalon
What makes up the metencephalon?
Pons + Cerebellum
What makes up the myelencepahlon?
The medulla.
What are the main apparatus for receiving inputs?
Dendrites.
What is a soma?
A cell body.
What are the four types of glial cells?
- Astrocytes
- Oligodendrocytes
- Schwann Cells
- Microglia
Where are astrocytes found?
Throughout gray and white matter.
What is the most numerous type of glial cell?
Astrocytes.
Where are oligodendrocytes found?
Throughout gray and white matter.
How common are microglia?
Make up 1% of CNS cell population.
What is the function of an astrocyte?
High potassium permeability which keeps other neurons from accidentally depolarizing. Also play an important role in development and injury of neurons
What is the function of oligodendrocytes?
Produce myelin for axons from multiple neurons in CNS and has proteins which inhibit axonal growth.
What is the function of Schwann cells?
Produce myelin for one segment of axons in PNS. and encourage growth post injury.
What are the size characteristics of schwann cells?
Large and medium nerve fibers, peripheral nerve fibers that also have connective tissue sheaths.
What is the function of microglia?
Scavenge post injury.
What is the function of the pons?
Relay station between cerebral cortex and cerebellum and descending motor fibers.
What is the function of the cerebellum?
Coordination of smooth motor movement.
What is the function of the midbrain?
Visual and auditory reflex pathways, visceral functions.
What is the function of the hypothalamus?
A variety of autonomic and behavioral functions.
What is the function of the thalamus?
All sensory info except olfaction passes through here, and transmits info to specific sites in cortex. Relays motor control info.
What are the three projections of the dura mater?
- Falx cerebri
- Tentorium cerebelli
- Falx cerebelli
What is the falx cerebri?
separates the cerebral hemispheres
What is the tentorium cerebelli?
separates posterior cerebral hemispheres from cerebellum
What is the falx cerebelli?
separates the cerebellar hemispheres.
