Nervous Integration Flashcards
How many spinal nerves are there and what is their distribution?
31 pairs of spinal nerves
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccygeal
How are the spinal nerves named?
Cervical nerves named for the vertebra below them
- except for cervical nerve 8 b/c theres only 7 cervical vertebrae
- Cervical nerve 8 exits below C7 and above T1
- Cervical nerve 1 below occiput and abov 1st cervical vertebra
Thoracic, Lumbar, Sacral, and coccygeal nerves are named for the vertebra above them
What composes a typical spinal nerve?
A mixed nerve with efferent and afferent neurons
Contains Connective tissues
- endoneurium
- perineurium
- epineurium
What purpose does insulation serve in a typical spinal nerve?
allows you to disrciminate between sensory input
- one axon per region
- impulse on axon doesn’t stimulate other axons because of insultation
What are dermatomes? What are the dermatomes in the picture?
Every piece of skin has adesignated spinal nerve that innervates it
-except face
What are the cranial nerves and hw many of them are there?
12 pairs of cranial nerves
Motor components
-arise from brainstem gray matter
Sensory components
-arise from ganglia outside brain
What is the cranial nerve mnemonic?
What is the cranial nerve function mnemonic?
Draw the weird cranial nerve picture
What are the essential functions of the nervous system?
- Sense changes in the internal and external environments
- Integrate and interpret incoming sensory information
- Respond, if necessary to environmental changes
What is a sensation?
stimulus sensed and sent to CNS
How is a sensation different from perception?
a perception is a sensation that is also routed to cerebral cortex and you are aware of it
What are the levels sensation?
- spinal (reflex only)
- brainstem (reflex only)
- thalamus (crude perception)
- cerebral cortex (precise perception)
What is sensory modality?
Specific types of receptor based on sense
-eg can’t feel cold with heat receptors
What are the components of sensation?
- Stimulation - stimulus + Receptor
- Transduction - receptor tranduces stimulus to sensory neuron
- Conduction - conduction of nerve impulse
- Translation - synapse in CNS not necessarily consciousness
What are generator potentials?
- stimulation of receptor directly causes depolarization of sensory neuron
- action potential is initiated if the stimulus is a threshold stimulus
- all receptors do this except those for the special senses