Chapter 6 Flashcards
Threshold
the point above which a stimulus is perceived and below which is not perceived. The threshold determines when we first become aware of the stimulus.
Absolute Threshold
the minimum amount of stimulus energy that a person can detect 50% of the time.
Subliminal Stimulus
an amount of stimulus energy that is below a person’s absolute threshold and consequently the person is not consciously aware of the stimulus
Just Noticeable Difference (JND or Difference Threshold)
the smallest increase or decrease in the intensity of a stimulus that a person is able to detect 50% of the time.
Weber’s Law
the increase in intensity of a stimulus needed to produce a just noticeable difference grows in proportion to the intensity of the initial stimulus
Sensation
our first awareness of some outside stimulus. An outside stimulus activates sensory receptors which in turn produce electrical signals that are transformed by the brain into meaningless bits of information.
Perception
the experience we have after our brain assembles and combines hundreds of individual, meaningless sensations into a meaningful pattern or image. However, our perceptions are rarely exact replicas of the original stimuli. Rather, our perceptions are usually changed, biased, colored, or distorted by our unique set of experiences.
Transduction
the light waves are absorbed by photo receptors. The electrical signals are changed into impulses that travel to the brain.
Primary Areas of the Brain
Occipital Lobe
Temporal Lobe
Parietal Lobe
Frontal Lobe
Association Areas of the Brain
They change meaningless bits into meaningful images, called perceptions.
Top-Down Processing
Perception is guided by previous knowledge, experience, beliefs, or expectations to recognize the whole pattern
Bottom-Up Processing
Perception begins with bits and pieces of information that, when combined, lead to the recognition of a whole pattern
Gestalt Psychologists
They believed that our brains follow a set of rules that specify how individuals elements are to be organized into a meaningful pattern or perception.
Rules of Organization
They were identified by Gestalt psychologists. They specify how our brains combine and organize individual pieces or elements into a meaningful perception.
Figure-Ground Rule
in organizing stimuli, we tend to automatically distinguish between a figure and a ground: The figure, with more detail, stands out against the background, which has less detail.
Closure Rule
in organizing stimuli, we tend to fill in any missing parts of a figure and see the figure as a complete.
Proximity Rule
in organizing stimuli, we group together objects that are physically close to one another.
Similarity Rule
in organizing stimuli, we group together elements that appear similar.
Simplicity Rule
stimuli are organized the simplest way possible
Continuity Rule
in organizing stimuli, we tend to favor smooth or continuous paths when interpreting a series of points or lines.
Perceptual Constancy
refers to our tendency to perceive sizes, shapes, brightness, and colors as remaining the same even though their physical characteristics are constantly changing.
Size Constancy
Our tendency to perceive objects as remaining the same size even when their images on the retina are continually growing and shrinking
Shape Constancy
Our tendency to perceive an object as retaining its same shape even though when you view it from different angles, its shape is continually changing its image on the retina
Brightness Constancy
Our tendency to perceive brightness as remaining the same in changing illumination
Color Constancy
Our tendency to perceive colors as remaining stable despite differences in lighting
Depth Perception
the ability of your eye and brain to add a third dimension, depth, to all visual perceptions, even though images projected on the retinal are in only two dimensions, height and width
Binocular Depth Cues
they depend on the movement of both eyes
Convergence
a binocular cue for depth perception based on signals sent from muscles that turn the eyes. To focus on near or approaching object, these muscles turn the eyes inward, toward the nose. The brain uses the signals sent by these muscles to determine the distance of the object
Retinal Disparity
a binocular depth cue that depends on the distance between the eyes. Because of their different positions, each eye receives a slightly different image. The difference between the right and left eyes’ images is the retinal disparity. The brain interprets a large retinal disparity to mean a close object and a small retinal disparity to mean a distant object.
Monocular Depth Cues
produced by signals from a single eye. Monocular cues most commonly arise from the way objects are arranged in the environment.
Relative Size
a monocular cue for depth that results when we expect two objects to be the same size and they are not. In that case, the larger of the two objects will appear closer and the smaller will appear farther away.
Interposition
a monocular cue for depth perception that comes into play when objects overlap. The overlapping object appears closer, and the object that is overlapped appears farther away.
Atmospheric Perspective
a monocular depth cue that is created by the presence of dust, smog, clouds, or water vapor. We perceive clearer objects as being nearer, and we perceive hazy or cloudy objects as being farther away.
Light and Shadow
they make up monocular cues for depth perceptions: brightly lit objects appear closer while objects in shadows appear farther away.
Motion Parallax
a monocular depth cue based on the speed of moving objects. We perceive objects that appear to be moving at high speed as closer to us than those moving more slowly or appearing stationary.
Texture Gradient
a monocular depth cue in which areas with sharp, detailed texture are interpreted as being closer and those with less sharpness and poorer detail are perceived as more distant
Cultural Influences
persuasive pressure that encourage members of a particular society or ethnic group to conform to shared behavior, values, and beliefs.
Impossible Figure
a perceptual experience in which a drawing seems to defy basic geometric laws.
Perceptual Sets
learned expectations that are based on our personal, social, or cultural experiences. These expectations automatically add information, meaning, or feelings to our perceptions and thus change or bias our perceptions.
Self-Fulfilling Prophecies
having strong beliefs about changing some behavior and then acting, unknowingly, to change that behavior.
Illusion
a perceptual experience in which you perceive an image as being so strangely distorted that, in reality, it cannot and does not exist. An illusion is created by manipulating the perceptual cues so that your brain can no longer correctly interpret space, size,and depth cues.
Ames Room
The room is built at an angle to show that our perception of size can be distorted by chaning depth cues
Extrasensory Perception (ESP)
a group of psychic experiences that involve perceiving or sending information outside normal sensory processes or channels
Telepathy
the ability to transfer one’s thoughts to another or to read the thoughts of others
Precognition
the ability to foretell events
Clairvoyance
the ability to perceive events or objects that are out of sight
Psychokinesis
the ability to exert mind over matter (ex: moving objects without touching them)
Ganzfeld Procedure
a controlled method of eliminating trickery, error, and bias while testing telepathic communication between a sender and a receiver
Prosopagnosia
a condition marked by a difficulty or inability to recognize faces
Phi Movement
the illusion that lights that are actually stationary seem to be moving. The illusory movement, which today is called apparent motion, is created by flashing closely positioned stationary lights at regular intervals
Real Motion
your perception of any stimulus or object that actually moves in space
Apparent Motion
an illusion that a stimulus or object is moving in space when, in fact, the stimulus or object is stationary. The illusion of apparent motion is repeated by rapidly showing a series of stationary images, each of which has a slightly different position or posture than the one before.
Virtual Reality
a perceptual experience of being inside an object, moving through an environment, or carrying out some action that is created or stimulated by computer
