CNS 1 Flashcards
Parts of nervous system
Central nervous system
Brain and spinal cord
peripheral nervous system
Autonomic and somatic
sympathetic nervous system
- part of autonomic nervous system
- fight or flight
parasympathetic
rest and digest
somatic
- part of peripheral nervous system
- voluntary control of skeletal muscles
white matter
high density of myelin covering axon pathways (and very few neurons)
gray matter
high density of neurons and dendrites (axons also present)
nucleus
cluster of neurons within the CNS
ganglion
cluster of neurons outside of the CNS
cortex
dense layers of neurons
tract
axons within the CNS traveling as a group/usually named based on region of origin and termination
i.e. spinocerebellar tract
pathway
similar to tract however it relates more to synaptically connected neurons performing a function
spinal cord function
- associated nerves: Dorsal and ventral roots
- primary function:
- sensory input
- reflex circuits
- somatic and autonomin motor output
dorsal root
- posterior
- sensory
- afferent (towards the brain)
- joins with the ventral root to form the spinal nerve
ventral root
- anterior
- efferent (exiting the brain)
- motor
- joins with dorsal root to form spinal nerve
brainstem
- medulla, pons, and midbrain
- 12 associated cranial nerves
reticular formation
- part of brainstem
- receives a summary of much of the information that enters the spinal cord and brain stem.
- filters information and excludes irrelevent stimuli
- regulates arousal
medulla
- Associated nerves:
- cranial VIII-XII
- functions:
- subconscious CV and respiratory control
- early relay nuclei in auditory, balance/equilibrium, taste
- head and neck control
- brainstem reflexes
- sets baseline tone for blood vessels
Pons
- Associated nerves:
- Cranial nerves V-VIII
- functions:
- respiratory control
- urinary control
- motor control of the eye
- sensation and motor control of the face
- ventral:
- pontine nuclei relay movement and sensation info from cortex to cerebellum
- dorsal:
- taste and sleep
pontine nuclei
- ventral (motor) part of pons- relays movement and sensation information from cortex to cerebellum
Midbrain
- Associated nerves:
- Cranial nerves III-IV
- functions:
- acoustic relay and mapping (processing hearing)
- eye movement, lens, and pupil reflex
- pain modulation
- contains nuclein and relay pathways critical for motor coordination
- i.e. substantia nigra
Cerebellum
- Associated nerves:
- cranial nerve VIII
- function:
- coordination and equilibrium
- helps make smooth, coordinated muscles
- motor learning
- sensory association/language
- coordination and equilibrium
- **found to not be necessary for life
thalamus
- associated nerves:
- cranial nerve II
- functions:
- sensory and motor relay/coordination btw cerebral hemispheres and lower CNS regions
- sensory modulation and gating
- regulation of cortical activation (attention and consciousness)
- without thalamus engaged, we can’t be conscious
- visual input