Sensation and Perception Flashcards
(28 cards)
What is the difference between sensation and perception
Sensation is the detection of physical stimuli located outside the mind. While perception is the selection, organization and interpretation of sensations.
What is Psychophysics and what perspective did it directly come from? what are the two types of thresholds measured through psychophysics and how are they graphed?
Psychophysics is the physical stimuli in relation to the subjective experience. Came from the signal detection theory
what are the two types of thresholds measured through psychophysics and how are they graphed?
- Absolute threshold: The minimal amount of physical stimulus that generates a conscious experience. Represented as a s curve
- Difference threshold: the minimal amount of change of a physical stimulus to create a just noticeable difference(JND)
Represented as a logarithmic curve- all are exponential
- What is signal detection theory?
Signal detection theory- nothing is ever sensed in isolation(background noise)
Webers Law
Not a consistent amount but it’s a consistent proportion
When attempting to detect a stimulus, what are the four possible outcomes (i.e. based on the presence or absence of the stimulus and on whether or not the subject thinks they have detected, or not, the stimulus)?
- Signal is there, person detects it(hit)
- Signal is not there, person detects it(false alarm)
3.Signal is there, person does not detect it(miss) - Signal is not there, person does not detect it(correct rejection)
- For all senses, what is the physical stimulus and how do the attributes of the physical stimulus relate to features of our conscious perception? (e.g. what about the physical stimulus is encoded as color?). For some, this may be unknown, but you need to know that we don’t know.
This is done by the use of many implicit(unconscious) rules for how to combine sensory info, or how to infer something new about the world based on the simple senses. If there is an excitatory effect and if there is inputs of colors
What are sensory receptor cells?
Cells that detect stimuli from the world that is processed in the brain.
Sight
Photo receptors found in the retina
Hearing
Hair cells found in the cochlea
Taste
taste receptors founds in the taste buds of papillae
Smell
olfactory receptors found in the olfactory epithelium
- Touch
warm and cold receptors embedded in the skin and pressure receptors found at the base of hair follicles
How is color perceived
Color is perceived for survival to associate reds with fruits to discrimate from vegetation such as grass
b. Trichromatic theory
relates color perception to cone receptions based on three colors blue(s cones), green(m cones) and red( L cones).
c. Opponent process theory :
The idea that perception is skewed based on color because the ganglion cells in the retina receive excitatory input from one type of cone and inhibitory input from another type.
- What is the idea about perception that comes from the Gestalt perspective (discussed in class).
a. Gestalt memory is all about context. The idea is that the whole is greater than its parts.
i. Proximity
Close figures are grouped as an object
ii. Similarity:
Similar figures are grouped in an object
Continuity:
Intersecting lines are interpreted as continuous
iv. Closure:
Figures with gaps are interpreted as complete
v. Illusory contours:
: contours are perceived even when they do not exist.
What cues gives rise to depth perception and which one perceives size
1.Binocular depth perception causes binocular disparity which is the difference in the location of an object as seen by the left and right eyes
2. Monocular depth perception is related to perception of size relative size associates objects in the distance as smaller opposed to an object close. Familiar size is where objects with familiarity can be inferred how far they are.
How is motion detected?
It is inferred.
