October 27, 2014
Week Three Worksheet
1. Describe why humans have a blind spot:
a. Humans have a blind spot because the spot that the axons meet to form the optic nerve does not have any sensor cells.
2. Describe the functional and anatomical differences between rods and cones:
a. Rods: Respond to faint light and are more abundant in the periphery of the eye. Cylindrical shape, similar to a welding rod.
b. Cones: Responsible for color vision, provide roughly 90% of input to the brain, and has to do with heightened visual responses. Looks like a cone.
3. Describe the trichromatic and opponent-process theories of color vision:
a. Trichromatic Theory: Perception of color occurs through three kinds of cones; short wavelength (blue), medium-wavelength (green), and long-wavelength (red). Each cone responds to colors, but some respond stronger to certain colors. For instance, the long-wavelength cones respond best to reds. Intense light increases the brightness of the color, but it does not change the color itself.
b. Opponent-Process Theory: Color is perceived in paired opposites. There are two mechanisms in the brain; one perceives color on a continuum from red to green, and the other from yellow to blue. This theory suggests that bipolar cells are excited by one set of wavelengths, and could be inhibited by another.
4. Trace the process of interpreting auditory information from the stimulus to the interpretation.
a. Auditory information is received through our ears which has three parts; outer ear, middle ear, and inner ear. Each part is responsible for picking up different signals. The outer ear helps us locate the source of a sound. The middle ear transforms waves into stronger waves to be interpreted. The inner ear transmits these waves through viscous fluid in the inner ear, and a signal is sent to the brain representing what was heard.
5. Name and describe the major structures of the middle