Unit 4- Sensation And Perception Flashcards
Sensation
The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
Prosopagnosia
Face blindness- sensation is fine but her perception is off (Heather Sellers)
Perception
The process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
Bottom-up processing
Analysis that begins with the sensory receptors and works up to the brain’s integration of sensory information
Top-down processing
Information processing guided by higher level mental processes, as when we construct perceptions drawing on our experience and expectations
Selective attention
The focusing of conscious awareness on a particular stimulus
Cocktail party affect
Ability to attend to only one voice among many
Inattentional blindness
Failing to see visible objects when our attention is directed elsewhere
Change blindness
Failing to notice changes in the environment (giving directions, change people)
There is also change deafness–not noticing change in voices
Choice blindness
We fail to notice when we are presented with something different than what we want/choose and we come up with reasons to defend that choice
Pop-out phenomenon
We don’t choose to attend to these stimuli, they draw our eye and demand our attention
Psychophysics
The study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them
Absolute threshold
- Gustav Fechner studied our awareness of faint stimuli and called them our absolute threshold
- the minimum stimulation needed to detect a particular stimulus 50% of the time
Subliminal stimuli
Stimuli we detect less than 50% of the time
Signal detection theory
A theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes their is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivations, and alertness
Subliminal
Below one’s absolute threshold for conscious awareness
Priming
The activation, often unconsciously, of certain associations, thus predisposing one’s perception, memory, or response
Difference threshold (just noticeable difference)
The minimum difference between two stimuli required for detection 50% of the time
Weber’s law
The principle that, to be perceived as different, two stimuli must differ by a constant percentage (rather than a constant amount)
Sensory adaptation
Diminished sensitivity as a consequence of constant stimulation
Jumpy eye
Sights don’t vanish because our eyes are always moving, gaze jumps from one spot to another every third of a second
Transduction
Conversion of one form of energy into another (transform). In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brains can interpret
Electromagnetic spectrum
Ranges from short waves of gamma rays (violet), to the narrow band we see as visible light, to the long waves (red) of radio transmission
Wavelength
The distance from the peak of one light or sound wave to the peak of the next