Sensation and Perception Flashcards
Sense
How receptors detect information
Perception
Interpretation of sensations
Bottom-Up Processing
Analysis of the stimulus begins with the sense receptors and works up to the level of the brain and mind.
Top-down Processing
Information processing is guided by higher-level mental processes as we construct perceptions, drawing on our experience and expectations.
Analysis of the stimulus begins with perception and expectations
Cocktail party effect
You can hear one voice among many
If someone says your name from far away
Selective Attention
Directing our awareness to relevant stimuli while ignoring relevant stimuli in the environment.
Divided Attention
While we can perform some simple motor skills simultaneously (walking and chewing gum), for more cognitively complex tasks, we can focus on only one thing at a time
Inattentional blindness
Failing to see visible objects when our attention is directed elsewhere
Change Blindness
A type of inattentional blindness
The inability to see changes in our environment when our attention is elsewhere.
Choice Blindness
the failure to recall a choice immediately after we have made that choice
- similar faces
Pop-Out Effect
A visual stimulus that has mostly similar-looking objects but one differing object that pops out or stands out very noticeably from the other objects
Absolute Threshold
Smallest detectable level of a stimulus
The minimum stimulation necessary to detect a particular light, sound, pressure, taste or odor 50% of the time. (listening to pitches during a hearing test)
Difference threshold
Just noticeable difference
Ability to sense the difference between 2 stimuli
Weber’s Law
To notice a difference, two stimuli must differ by a constant proportion percentage (not a constant amount)
Signal Detection Theory
Predicts how and when we detect the presence of a faint stimulus (signal) amid background noise (other stimulation).
There is no single absolute threshold
Detection depends on
Person’s experience
Expectation
Motivation
Level of fatigue
Subliminal Stimulation
We process info below the absolute threshold for conscious awareness
To predispose one’s perception, memory, or response
Unconscious processing
Sensory Adaptation
Diminishing sensitivity to an unchanging stimulus
After constant exposure to a stimulus, our nerve cells fire less frequently
An adjustment of the senses to the level of stimulation they are receiving
The constant quivering of our eyes allows us to minimize sensory adaptation for vision
The smell in your friend’s house goes away after a few minutes
Gestalt
Instead of focusing on every small component, we see objects as part of a greater whole and as elements of more complex systems.
The brain creates a coherent perceptual experience that is more than simply the sum of the available sensory information
It does this in predictable ways
Common Region
Objects that are within the same region are perceptually grouped together
Similarity
when objects are similar you group them together
Proximity
we perceive objects which are close to one another as a group
closure
people will fill in blanks to perceive a complete object whenever an external stimulus partially matches that object
Continuity
elements that are arranged on a line or curve are perceived to be more related than elements not on the line or curve
Connectedness
when we see connections in disjointed objects
Figure Ground
Something is a figure and something is a background
Or something is a background and something is a figure
Depth Perception
Enables us to judge distances
Human infants have depth perception
Even newborn animals show depth perception.
Binocular Cues
Depth perception that we have because we have TWO eyes
Retinal disparity - binocular cue
Images from the two eyes differ. (how 3D works)
The amount of disparity (difference) between the two images
Can be used as a cue for distance
Convergence - binocular cue
Neuromuscular cues.
When two eyes move inward (towards the nose) to see near objects and outward (away from the nose) to see far away objects.
The angle formed at the convergence indicates the distance
Relative height
We perceive objects higher in our field of vision as farther away
Relative size
Relative size - If two objects are similar in size, we perceive the one that casts a smaller retinal image to be farther away
Interposition
Objects that block other objects tend to be perceived as closer
Linear perspective
Parallel lines appear to converge in the distance. The more the lines converge, the greater their perceived distance
Relative motion
Objects closer to a fixation point move faster and in opposing direction to those objects that are farther away from a fixation point, moving slower and in the same direction
Light and shadow
Nearby objects reflect more light than more distant objects
Objects that are shaded on top are seen as “sticking out toward us”
Phi phenomenon
The apparent motion created by lights flashing in sequence