exam 2 (ch 5-6, 8-9)

• Light enters the eye through an opening in the center of the iris called the?

  pupil
• Light from the left side of the world strikes the ____ half of the retina?

  right
• Light from the right side of the world strikes the ___ half of the retina?

  left
• Light from above strikes the _____ half of the retina?

  bottom
• light from below strikes the ____ half of the retina?

  top
• what is the rear surface of the eye & is lined with visual receptors?

  retina
• what is the type of neuron in the retina that receives input directly from the receptors?

  bipolar cells
• what is type of neuron in the retina that receives input from the bipolar cells?

  ganglion cells
• messages go from the receptors at the back of the eye to _____, located closer to the center of the eye?

  bipolar cells
• The bipolar cells send their messages to ____, located still closer to the center of the eye?

  ganglion cells
• The ganglion cells’ axons unite and travel back to the brain as the ___?

  optic nerve
• route within the retina?

  bipolar cells -> ganglion cells -> optic nerve
• what refines the responses of bipolar and ganglion cells, enabling certain ones to respond mainly to shapes, directions of movement, color, or other visual features?

  amacrine cells
• the blind spot is the area at the back of the retina where the ___ exits; there is no receptors?

  optic nerve
• what is the tiny area of the retina specialized for acute, detailed vision?

  fovea
• Toward the periphery of the retina, more and more receptors ____ onto bipolar and ganglion cells?

  converge
• which receptor is abundant in and near the fovea, are more useful in bright light and essential for color vision?

  cones
• which receptor is abundant in the periphery of the human retina, respond to faint light but are less useful in daylight because bright light bleaches them?

  rods
• are there more rods or cones in the human retina?

  rods
• in the Trichromatic Theory: Short-wavelength are ___ cones?

  blue
• in the Trichromatic Theory: medium-wavelength are ___ cones?

  green
• in the Trichromatic Theory: long-wavelength are ___ cones?

  red
• the wavelength of a light wave corresponds with?

  color
• the amplitude of a light wave corresponds with?

  brightness
• which color vision theory is the idea that we perceive color in terms of opposites?

  opponent process theory
• in the trichromatic theory of color vision, the three kinds of cones are?

  red, green, blue
• what are the opposites in opponent-process theory?

  red to green, yellow to blue, white to black
• what type of cell receives input from receptors and delivers inhibitory input to bipolar cells?

  horizontal cells
• The rods and cones of the retina make synapses with _____and bipolar cells?

  horizontal cells
• Where does the optic nerve start and where does it end?

  starts with the ganglion cells in the retina. ends at LGN of thalamus
• Most of the optic nerve goes to the _____of the thalamus?

  LGN
• what is the the reduction of activity in one neurons by activity in neighboring neurons?

  lateral inhibition
• information from the nasal half of each eye (the side closer to the nose) crosses to the ____ hemisphere?

  opposite
• Information from the temporal half (the side toward the temporal cortex) goes to the _____ hemisphere?

  same
• in lateral inhibition, light striking the rods and cones ____ their spontaneous output, and the receptors make ____ synapses onto the bipolar cells?

  decreases; inhibitory
• what respond with an excitatory response to light from one part of the spectrum and with an inhibitory response to light from another part?

  opponent neurons
• what is the Enhanced perception of short wavelengths during dark adaptation?

  purkinje shift
• rods v cones: Higher concentration in the peripheral retina?

  rods
• rods v cones: absent in the fovea?

  rods
• rods v cones: present in the fovea?

  cones