Unit 3 Flashcards
Sensation and Perception
Sensation
Information you take in. Sensory receptors (eyes, ears…) and the nervous system receive stimuli from the environment.
Senses
Sense organs transform physical stimulation into neural impulses that give us sensations. Light waves give us light and dark sensations.
Bottom-Up Processing
Body response. See, smell, touch, hear. Analysis that emphasizes the characteristics of the stimuli rather than our concepts or expectations.
Perception
How you interpret the information (sensation). Process of organizing and interpreting sensory information.
Top-Down Processing
Emotional response. Looks pretty/ugly, smells gross, feels rough, sounds loud. Analysis the emphasizes the perceiver’s expectations, concept memories, and other cognitive factors, rather than individual characteristics.
Psychophysics
Relationship between physical stimuli and our psychological experiences to them.
Absolute Threshold
Weakest amount of a stimulus required to produce a sensation.
Difference Threshold
Smallest difference in stimulation that can be detected. A just noticeable difference.
Weber’s Law
The noticeable difference of the stimulus is large when the intensity is high and vice versa.
Sensory Adaptation
Getting used to a level of stimulus. Sense organs are change detectors. Diminishing responsiveness of our sensory systems to prolonged stimulation. Unless it is intense or painful, stimulation that persists without change shifts to the background of our awareness.
Signal Detection Theory
The detection of a stimulus depends on the intensity of the stimulus and the physical and psychological state of the individual.
Sesory Overload
Over stimulating the senses.
Selective Attention
Focusing attention on selected aspects of the environment.
Divided Attention
Focusing attention on several aspects of the environment.
Cocktail Party Effect
You can hear your name across the room in another conversation.
Transduction
Process of stimuli changing from physical to neural. Converts energy such as light into neural messages. Begins with sensory neurons detecting physical stimuli. When stimuli reaches sense organ, activates receptors. Receptors convert excitation into a nerve signal.
Cornea
Protective outer layer.
Iris
Colored part of the eye. Muscle that constricts pupil.
Pupil
Opening in the iris. Changes shape in light and dark.
Lens
Changes shape to send best image to back of the eye. Flips the image upside down. Is an “accessory structure” in the body- modifies stimulus before transduction.
Retina
Back of the eye. Contains rods and cones. Transduction occurs here.
Photoreceptors
Light sensitive cells (neurons) that convert light energy to neural energy. Rods- black and white (125 mil/eye) vision. Cones- color vision (7 mil/eye)
Fovea
Area of sharpest vision. Highest concentration of cones.
Distal and Proximal Stimuli
Distal: what you see- exists in the real world
Proximal: inverted image the retina sends to the brain- image formed in the mind