Neuroanatomy Flashcards
what are afferent signals?
signals that move from the body to the brain (sensory)
what are efferent signals?
signals that move from brain to body (motor)
what is the central nervous system (CNS)?
the brain and the spinal cord
what is the peripheral nervous system (PNS)? what other systems does it contain?
- nervous tissue outside the brain and spinal cord
- somatic and autonomic nervous system
what is the somatic nervous system? what do it’s afferent and efferent signals do?
- conscious sensation and movement in relation to the outside world
- afferent - sensation of the outside world, touch
- efferent - movement in relation to the outside world
what is the autonomic nervous system? what do it’s afferent and efferent signals do?
- unconscious afferent and efferent signals
- afferent - sensation of internal environment (blood acidity, how much stomach is stretched)
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efferent - movement of internal environment without our conscious involvement
- sympathetic NS
- parasympathetic NS
what are the efferent systems of the autonomic nervous system? do they work bilaterally?
- sympathetic and parasympathetic nervous systems
- there is a unilateral sympathetic response across the body and extreme lateralization of response
what does the sympathetic nervous system do?
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mobilizes energy, fight or flight, main goal is to be ready for some action, maximize and mobilize energy/resources on hand
- heart pounds more to bring more O2 to the brain
- body starts creating more energy, ATP to use
- blood constricts to the core and the brain to prevent bleeding in limbs
what does the parasympathetic nervous system do?
- conserves energy, rest and digest, main goal is to store energy for later, digest faster
- not always mutually exclusive or in opposition to one another
- ex. healthy sexual activity
what are cell clusters?
cell clusters - grey matter regions
- nucleus, nuclei (CNS) vs. ganglion/ganglia (PNS)
what are bundles?
bundle of axons - white matter regions
- tract (CNS) vs. nerve (PNS) vs. fibres (all)
what are the anatomical directions when referring to quadrapedal animals?
- anterior (rostral) - head of the animal, posterior (caudal) - end of spinal cord of the animal
- dorsal/superior - spine side, ventral/inferior - stomach side
- lateral - towards the outside of the body, medial - towards the line of symmetry
what are the anatomical directions when referring to the bipedal neuroaxis of humans?
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anterior - head (including the midbrain), posterior - end of spinal cord
- after the midbrain, it switches
- anterior - front of our face,
- posterior - back of our head
-
dorsal- spine side, ventral - stomach side
- we don’t use the terms superior/inferior for the midbrain to botton of spine
- after the midbrain, it switches
- dorsal/superior - top of the head, ventral/inferior - bottom of the brain
- lateral - towards the outside of the body, medial - towards the line of symmetry
what is a coronal section?
cutting to separate front half of brain from the back half
what is a horizontal section?
cutting to separate the top of the brain from the bottom half
what is a mid-sagittal section?
cutting to separate sides of the brain down the middle
what is a sagittal section?
any cut separating the sides of the brain
what is the composition of the spinal cord from anterior to posterior?
- cervical, thoracic, lumbar, and sacral vertebrae protect the spinal cord
- intermittent projections form spinal cord because the spinal cord is protected by bones and the axons bundle together to squeeze through between bones
why does the spinal cord narrow as you go down the spine?
- narrows as you go down since the efferent neurons on the lower end leave to control parts of the body
- barely any sensory information coming in at the bottom of the spinal cord
- sensory axons increase as you move up the spinal cord
what is the cauda equina?
sack of nerve roots at the lower end of the spinal cord that leave the spinal cord to connect to other parts of the body
what does the composition of grey and white matter look like in the spine? what are the different parts responsible for?
- grey matter is on the inside and shaped like an H, white matter surrounding
- opposite of how white matter and grey matter are organized in the brain
- dorsal side of spinal cord is responsible for sensory information and ventral side is responsible for motor information
- motor cell bodies - cell bodies are in the grey matter of the spinal cord
- sensory cell bodies - cell bodies are in the ganglia outside the spinal cord (dorsal root ganglia)
why is the segment of damage of the spinal cord important?
- spinal cord damage is related to segment of damage
- closer to brain → worse damage
- affects all the motor and sensory axons/cell bodies below it
what are the 3 major divisions in the brain?
- forebrain, midbrain, hindbrain
- all appear in early development
what are the 5 major divisions in the brain?
- forebrain - telencephalon, diencephalon
- midbrain - mesencephalon
- hindbrain - metencephalon, myelencephalon