1. What are the four accepted criteria (from the lecture) that allow us to distinguish between sensory
systems? Be able to apply these criteria to vision, audition, and ESP.
There is a unique stimulus, a unique receptor, a unique nervous system, and a unique percept.
Pathway to brain
To see an image,
its light waves have
to strike your eye.
Light waves enter
eyeball through the
pupil, which determines
how much light enters.
Signals from left visual field go
to right portion of each retina, to
the optic nerve to optic chiasm,
and then through right thalamus
to right visual cortex.
As a result,
To hear something,
air molecules are
displaced by sound
These sound waves
move through outer ear
and make the eardrum
These signals travel along the
auditory nerve to the brain's
primary auditory cortex
As a result,
you hear the
2. How do we perceive color? Include a distinction between the trichromatic and the opponent-process
Color is determined by wavelengths of light, which activate certain types of cones. Trichromatic (red,
blue, green) explains color blindness, is at the retina, and all color vision result of activity of the 3
kinds of cones. Opponent-process theory (red/green, blue/yellow, black/white) explains after-image, is
at the thalamus, and ganglion input works in opposition.
3. Distinguish between the “what” and “where” visual system.
Neurons in different parts of the brain tend to have different receptive fields; ventral and dorsal
4. Distinguish between top-down and bottom-up processing.
Top-down: a hierarchical model of pattern recognition in which information at higher levels of
processing can also influence lower, “earlier” levels in the processing hierarchy. Expectations about
what we will perceive.
Bottom-up: a hierarchical model of pattern recognition in which data are relayed from one processing
level to the next, always moving to a higher level of processing. Sensory info.
5. Discuss the data on (re)gaining vision.
After regaining vision, a person may see the world in a different view or perception. Does perception
return to the same way it was before? A person may be able to detect colors and motion more well
than others after regaining sight.
What is pain?
It is part of a warning system that stops you from continuing activities that may harm you.
7. Note the Gestalt principles of perceptual organization.
It is the tendency to integrate pieces of information into meaningful wholes. The grouping principles
are proximity, similarity, continuity, closure, and connectedness.
8. How do we perceive depth?
Ability to see objects in 3 dimensions; allows us to judge distance. We are able to perceive depth in
these two-dimensional patterns because the brain applies the same rules or mechanisms that it uses
to work out the spatial relations between objects in the three-dimensional world.
9. Contrast sensation and perception.