Flashcards in Sensation and Perception Deck (18):
Name the type of photo receptor that is most sensitive to light
The rods do not perceive color but are most important for peripheral vision and, because they’re more sensitive to light, are responsible for vision in dim light.
Through what processes are sensation and perception integrated?
Through both top down (concept driven) and bottom up (data driven)
Theories of Color Vision
trichromatic theory and opponent process theory
What three colors are involved in the trichromatic theory?
the retina contains three types of color receptors (cones) – red, blue, and green. Applies to the initial stage of visual processing only.
What is inolved in the Opponnent Process Theory?
Opponent-process theory proposes that there are three types of opponent-process cells – red/green, blue/yellow, and white/black. It applies to processing beyond the retina and explains the phenomenon of afterimages and red/green and blue/yellow colorblindness.
What are the causes of color blindness?
Mainly genetic, however injury or disease (diabetes, MS)
Why is color blindness more common in males?
It’s more common in males because the abnormal gene is recessive in females, which means females would have to inherit it from both parents. Of the types of colorblindness, red/green is most common. (On X chromosome)
Differences between monocular and biocular cues?
When determining how far objects/things are from us we uses cues.
Monocular - uses one (mono) eye and depth perception at long distances. Biocular uses two (bi) and perceives depth at shorter distances - retinal disparity (each eye sees images on retina - brain computes distance and greater the distance between the two slightly different images - the closer it image to you) and convergece (cross eyed as objects get closer). Not great therefore for judging far away images. (See Crash Course Psychology - Perceiving is Believing).
Past pain experiences can influence how we currently experience pain? T/F
True - pain perception is moderated by several factors including current emotional state and past experience with pain.
What is the name of the theory that distinguishes between two types of nerve fibers in the spinal cord?
Gate Control Theory
What are the two types of nerve fibers involved in this theory
Small unmyelinated fibers are responsible for transmitting most pain signals to the brain, while larger myelinated fibers transmit other sensory signals.
How does this theory work?
Gate theory - states that pain is transmitted (or not) by small fibers and depends on a “gate” that is normally opened by incoming pain signals but is closed by the transmission of other sensory signals in the large fibers and by transmission of information from the brain. Consequently, pain can be relieved by, for example, applying heat or cold to the affected area of the body or by using distraction techniques, guided imagery, or hypnosis. (Think of when you get a cut or even a burn - and just holding the area around it makes is feel better)
What is psychophsyics?
the study of the relationship between the magnitude of physical stimuli and psychological sensations. eg.
Relationship between how hard you need to press on my arm to get a sensation
the more intense the stimulus, the greater the increase in stimulus intensity reqired for the increase to produce a just noticeable differece (JND) proportionate increase
a person's experience of stimulus intensity increased arithmetically as the stimulus intensity increases geometically. - You tube this.
Steven's Power Law
Weber and Fechner's laws work well for stimulus intensity at the middle range For extreme intensity Steven's developed a direct measure of sensation. Precitable. You tube this.
minimum stimulus needed to produce a sensation