Midterm 2: Central Nervous System Slides Flashcards
Where are sensory neurons located?
Partly in CNS and partly in PNS - unipolar
Where are interneurons located?
Completely in CNS - multipolar
Where are motor neurons located?
Partly in CNS and partly in PNS - multipolar
What are the components of the afferent division of the PNS?
Sensory stimuli (from touch, hearing, etc.) and visceral stimuli (from organs)
What are the components of the efferent division of the PNS and what does each one involve?
Somatic (voluntary - move skeletal muscle) and autonomic (automatic - goes to organs and controls them, which you can’t do)
What are the components of the autonomic division of the efferent division of the PNS?
Sympathetic (e.g., will increase activity for vital systems in emergency and decrease it for nonvital systems) and parasympathetic (“rest and digest”, or housekeeping)
What are the cells of the nervous system and what are their functions?
Neurons: excitable cells
Glial cells: support functions of neuron (more abundant than neurons)
What are some types of glial cells (5)?
Ependymal cells, astrocytes, oligodendrocytes, microglial cells, Schwann cells
Ependymal cells function
Produce CSF that bathes/surrounds brain
Astrocyte function
Link neuron to adjacent blood vessels, maintain chemical consistency, ensure neurons get adequate nutrients (most abundant glia)
Microglial cell function
Similar to immune cells; “cleaning crew” of cells
What determines brain sophistication and learning?
Amount of synapses and communication/connections
Structure and function of ventricles - name all four ventricles
Have ependymal cells in their lining, so they produce and circulate CSF - left lateral ventricle, right lateral ventricle, third ventricle, fourth ventricle
Function of interventricular foramen
Connect lateral ventricles with third
Function of cerebral aqueduct
Connects third and fourth ventricles
Function of central canal
CSF exits through here to spinal cord
What produces the CSF?
Group of cells and blood vessels collectively known as the choroid plexus (ependymal cells and blood vessels)
Functions of CSF (3)
Bathes the brain; acts as shock absorber; transports nutrients, chemical messengers, and waste products
What are the 4 lobes of the brain?
Frontal, Parietal, Temporal, Occipital
What are the areas of the frontal lobe and their functions?
Premotor cortex: Planning movement
Primary motor cortex: Initiates motor movements
Prefrontal association cortex: Complex thinking/tasks and cognitive functions
Broca’s area: speech initiation/production
What are the areas of the parietal lobe and their functions?
Somatosensory cortex: conscious awareness of general somatic senses, precisely localize stimulus received
Wernicke’s: overlaps in temporal lobe, speech comprehension
What is spatial discrimination?
You know exactly where sensation information is coming from (very precisely) without looking
Areas/functions of temporal lobe
Hearing, vision (visual association area for facial recognition), olfaction
Area/function of occipital lobe
Visual cortex (responsible for vision)
What are the major components of the brain (not lobes)
Cerebrum, cerebellum, thalamus, hypothalamus, brain stem
Functions of the thalamus
Relay station for all synaptic input (except smell), crude awareness of sensation, motor control
Functions of hypothalamus
Regulatory center: homeostasis such as temperature control, thirst, urine output, food intake Endocrine role (controls hormones) Regulation of sleep-wake cycle (internal clock) Formation of memory, information recall
Functions of cerebellum
“Small brain” - maintenance of balance, coordination and planning of skilled voluntary muscle activity
What does ipsilateral mean and what component does it involve?
Means same side, so right side of cerebellum control right side of body
Functions of the brain stem
Gateway to the brain, origin of majority of peripheral cranial nerves; control centers for digestive, respiratory, and cardiovascular centers (vital centers); equilibrium and posture; integration of inputs from spinal cord
What causes brain damage?
Trauma (blow to head), stroke, seizure
What happens in a stroke, and what’s another name for it?
Cerebral vascular accident; blood vessels supplying brain rupture or clot, brain cannot get nutrients (since blood can’t be delivered) causing serious damage
What happens during a seizure
Not well understood why they happen, but brain fires uncontrollably causing compulsive shock
What are the language areas of the brain and where can they be found?
Wernicke’s and Broca’s areas; found in left hemisphere only
What is Wernicke’s aphasia?
Someone can speak bu can’t understand what they’re saying
What is Broca’s aphasia?
Someone can’t speak but can understand
What happens in contralateral neglect syndrome?
After person experiences trauma to one side of the brain, they lose interest and don’t care about the other
What’s different about a split-brain patient?
Corpus callosum has been cut, so two hemispheres can’t communicate
What does contralateral mean?
E.g., right side of brain controls left side of body (and vice versa)
