Exam 1 Flashcards
Cells of the Nervous System
- neurons
2. glial cells
neurons
receive and transmit electrochemical signals
glial cells
various types, provide a wide variety of supportive functions
what are the 3 components to a neuron
- cell body or soma
- dendrites
- axon
Neurons _____ info across small spaces, _____ receives info
send; dendrites
cell body/soma
contains genetic material in nucleus, providing nutrients that cell needs
dendrites
receive info from adjacent neurons, membrane has receptors where info is transferred
axon
- transmits info into nearby neurons
- thin fiber of constant diameter, only 1 per neuron
- at end of axon: presynaptic terminals
several axons running together
nerve (when outside the brain) or tract (when inside the brain)
presynaptic terminals
the point at which neurotransmitters are released and signal is passed to another neuron
synapse
gap between adjacent neurons through which signals are sent (space between neurons)
three types of neurons
- sensory neurons
- interneurons
- motor neurons
sensory neurons
convey sensory info to brain
- bring sensory info from body to brain (what we see, hear, etc.)
interneurons
carry out operations involved in thought, feeling, and planning action
motor neurons
transmit commands out into the body to control muscles and organs
afferent
bring info into a structure (the brain) (admission)
efferent
carry info away from a structure (exit)
Glia
provide important roles
serve as a support system
types of glia
- astrocytes
- microglia
- oligodendrocytes
- schwann cells
astrocytes
largest, many functions
- humans have 1.4x astrocytes per neuron
microglia
involved in response to injury/disease
smallest
increase in microglia in altzheimers
oligodendrocytes
responsible for producing myelin, in brain/spinal cord
schwann cells
responsible for producing myelin, rest of nervous system
multiple sclerosis
immune system attacks the myelin surrounding axons, death of oligodendrocytes
- sensory info isnt getting in because myelin isnt sending info to motor neurons, signaling speed is low
(demyelination of axons)
grey matter
cell bodies (and dendrites), generally outside of brain
white matter
axons (generally outside the brain)
the central nervous system
outer service is cortex = mostly the cell bodies of neurons
includes the brain and spinal cord
2nd part is peripheral nervous system
2nd part is peripheral nervous system
- nervous tissue outside the skull and spine
- serves to bring info into the CNS and carry signals out of the CNS
- somatic
peripheral nervous system
somatic, system out of the body, conveys sensory info into CNS from body
- conveys motor commands from CNS to muscles
cranial nerves
bell’s palsy
somatic nervous system
autonomic nervous system
cranial nerves
movement in different areas
- some bring in sensory info, eye movement, tongue, neck
bell’s palsy
swelling compression of the 7th cranial nerve on one side
- twitching, paralysis, drooling, drooping eyelid/mouth
somatic nervous system
afferent nerves (sensory) efferent nerves (motor)
autonomic nervous system
sympathetic and parasympathetic nerves -> generally have opposite effects
- both are efferent
- sympathetic: “fight/flight” (controlling internal organs)
parasympathetic nerves rest and restore, rest and digest, slow down heart, when you’re not stressed
spinal cord
neurons in central nervous system don't come back - cell bodies don't come back cervical spinal cord thoracic spinal cord lumbar sacral
thoracic spinal cord
branches out to torso and inner arms
lumbar
fronts of legs
sacral
backs of legs and genetalia
spinal cord injury
football player kevin everett was initially paralyzed from shoulders down, spine fractures but spinal cord not severed
gyrus
ridges/grooves
fissure
large groove (separates the brain)
telencephalon
cerebral cortext
- lateral fissure: groove that separates the frontal and temporal lobes
- central fissure/sulcus: a groove that separates the frongal and parietal lobes
- longitudinal fissure: a groove that separates left from right side
- corpus callosum: connects 2 hemispheres
4 lobes of cerebral cortex
- frontal
- parietal
- temporal
- occipital
frontal
motor function, decision making
- prefrontal: higher executive functioning (ex. emotional regulation)
lobotomies
1940s and 1950s
disconnect prefrontal cortex from rest of the brain
parietal
somatosensory, sensation of our body, responsibility in touch
temporal
auditon, emotion
occipital
vision
Subcortical Structures of the Telencephalon
limbic system, basal ganglia
limbic system
feeding, fighting, fleeing, fucking
includes hippocampus, mammillary bodies, amygdala, fornix, cingulate cortex septum
basal ganglia
motor
Diencephalon
helps us use senses together
thalamus; sensory nuclei
hypothalamus: motivated behaviors, control hormone release
mesencephalon
audition, vision, analgesia, sensorimotor
metencephalon
pons, cerebellum, coordination
