Unit Four Flashcards
Sensation
Process where our sensory receptors and nervous system receive and represent stimulus energies from our environment
Perception
Process of organizing and interpreting sensory info enabling us to recognize meaningful objects and events
Bottom up processing
Start with sensory receptors and work to brain integration of sensory info
Ex lines angles and colors forming picture
Top down processing
Construct perceptions Drawing on our experience and expectations,
Ex consider title, apprehensive expressions then direct attention to aspects that give those observations meaning I
Selective attention
Focusing of conscious awareness in particular stimulus
Inattentional blindness
Failing to see visible objects when our attention is directed elsewhere
Change blindness
Failing to notice changes in the environment
Psychophysics
Study of relationships between physical characteristics of stimuli (like intensity) and our psychological experience with them
Absolute threshold
The minimum stimuli needed to detect a particular stimulus 50% of the time
Signal detection theory
Theory predicts when we will detect weak signals (measured as ratio of hits to false alarms)
What does signal detection theory believe detection depends on
Persons experience, expectations, motivation, and alertness
Subliminal
Below ones absolute threshold for conscious awareness
Priming
The activation, often unconsciously, of certain associations, predisposing ones perception, memory, or response
Difference threshold
Minimum difference between two stimuli required for detection 50% of time
(Just noticeable difference)
Webers law
Principle that to be perceived different two stimuli must differ by a constant percentage (rather than amount)
Sensory adaptation
Diminished sensitivity as a consequence of constant stimulation
Transduction
Conversion of one form of energy into another, like senses into neural impulses for brain to interpret
Wavelength
Distance from the peak of one wave to the peak of the next
Determined hue/color
Hue
Dimension of color that is determined by the wavelength of light
Intensity
Amount of energy in a wave, perceived as brightness or loudness, and determined by amplitude or height of wave
Pupil
Adjustable opening in the center of the eye through which light enters
Iris
Ring of Colored muscle tissue, controls pupil size opening
Lens
Transparent piece behind pupil, chances shape to help focus images on retina
Retina
Light sensitive inner surface of eye, contains receptor rods, cones, and layers of neurons that begin process visual info
Rods
Retinal receptors that detect black, white, grey, necessary for peripheral vision and twilight
Cones
Retinal receptors that are in the center of the retina, function in daylight or well light,they detect fine detail and color sensation
Optic nerve
Nerve that carries neural impulse from eye to brain
Blind spot
Point at which optic nerve leaves eye, blind because no receptor cells are there
Fovea
Central focal point in the retina, where the cones cluster around
Feature detectors
Nerve cells in brain that respond to specific features of stimuli
Ex shape, angle, movement
Parallel processing
Processing many aspects of a problem simultaneously, sub dimensions like color, movement, form and depth.
What does parallel processing contrast with
Step by step and conscious problem solving
Young helmholtz trichromatic (3 color) theory
Theory retina contains three different color receptors (red, blue, green) and when stimulated in combination it produces perception of any color
Opponent process theory
Opposing retinal processes enable color vision (blue-green, yellow-blue, black_white) explains after images. Ex some cells stimulated by red and not green, vis versa
Audition
Sense or act of hearing
Frequency
Number of complete wavelengths that pass a point in a given time, determines pitch