day 9 bio

  1. Optic chiasm
    point at which some of the axons of retinal ganglion cells cross
  2. left nasalhemiretina and right temporal hemiretina look at whcih direction?
  3. Order in which information is processed in visual systems?
    • 1. retina then
    • 2. lateral geniculate nucleus
    • 3. primary visual cortex
  4. how is perception created?
    light information has to reach visual primary cortex
  5. Hubel and wiesel recorded from 3 different regions
    -retinal ganglion cells

    -lateral geniculate nucleus of thalamus

    -layer 4 cells of primary visual cortex
  6. organization of visual cortex
    neurons grouped in vertical columns all share same general visual area
  7. Dorsal stream
    • -appears to be important in determining WHERE?
    • *damage here: prevents people from reaching out and grabbing objects
    • **they may know what the object is though
    • ***goes up the brain
  8. ventral stream
    • -appears to be important for identifying WHAT an object is
    • *admage here: no problem reaching for the objects
    • **cannot recognize what they are
    • ***goes down the brain
  9. Physical stimulus for vision is...
    • -light
    • *wavelengths will effect what color we see
    • *size of the wave will effect the intensity (brightness)
  10. physical stimuli for taste and olfaction are...
    • -molecules
    • *found in food, fluid, and air
  11. physical stimuli for audition are...
    • vibrations of air molecules
    • *sound vibraitons
  12. importance of the ear...
    -for sound localization ad funneling vibrations to the sense organ
  13. (turning vibrations into neural signals) sound waves travel down the auditory canal and...
    impact on the tympanic membrane (eardrum)
  14. 3 small bones are on the other side of the tympanic membrane, whcih are?
    • ossicles
    • *malleus
    • *incus
    • *stapes
  15. how do the ossicles move?
    movement of the tympanic membrane moves the bones
  16. what do the ossicles provide for hearing?
    -amplify sound
  17. Organ of corti
    • -fluid-filled spiral with inner finger-like structure
    • *sense organ of audition
  18. deflection of hair cells in one direction mechanically causes...
    ion channels to open
  19. conversely, deflection of hair in the other direction...
    prevents ion channel openings
  20. receptors for sound are...
    hair cells
  21. depolarization of a hair cell ultimately causes...
    • NT released from it onto neurons and cause AP to be generated.
    • *these neurons leave the ear as the auditory nerve then go to CNS
  22. (receptive fields in cochlea) tones of different frequencies will cause...
    hair cells in different parts of the cochlea to be stimulated
  23. (receptive fields in cochlea) REGIONS of the cochlea that respond best to one tone...
    can be thought of as having a receptive field for that tone
  24. Cochlea has a tonotopic map
    regions of the cochlea that respond best to one tone are neighbored by regions that respond best to a tone of a slightly different frequency
  25. medial geniculate nucleus
    region of the thalamus that processes auditory information
  26. where are the primary and secondary  cortex located?
    temporal lobe

    ***it is organized in columns
  27. what prevents the ossciles from vibrating too muhc?
  28. anteriro auditory pathway
    • what?
    • *going left
  29. posterior auditory pathway
    • where?
    • *to the right of brain
  30. Semi-circular canals
    -located next to cochlea

    -sense organ for the vestibular system
  31. specific description of semi-circular canals
    • sense organ
    • -information related to head movements and intensity of head movements
    • -important for balance
  32. how do semi-circular canals translate head movements to neural signals? (3) the movement of the fluid in the semi-circular canals and the stimulaton of hair cells

    2.infor from hair cells traveled out of auditory nerve

    3. info is proceseed by brainstem and cerebellum

    4.system works with visual system
  33. vestibulo-ocular reflex
    -able to focus in what you are looking at regardless of movement

    **balance and visual
  34. causes of bed spins
    -alcohol changes density of fluid in semi-circular canals causing to keep stimulating hair cells even when youre not moving

    -mostly exaggertaed at night becaus ebrain cannotuse visual processes to let you know worls is still
Card Set
day 9 bio
biopsych audition