OUTLINE – Modules 10, 11, 12 13SENSATION1. Sensation vs. Perception2. Psychophysics3. Vision4. AuditionPERCEPTIONPSYCHOPHYSICSWhat is it?Light brightnessKey concepts:Absolute Thresholds – smallest magnitude of a stimulus that can be reliably discriminated from NO stimulus at least 50% of the timeDifference Threshold – minimum difference between two stimuli that a person can detect at least 50% of the timePSYCHOPHYSICSSignal Detection Theorypredicts how and when we detect the presence of a stimulus amidst background stimulationPoint:Absolute thresholds and Just noticeable differences are not fixedOur sensitivity to a stimulus varies based on experiencesFactors that affect Absolute and Difference Thresholds:WavelengthThe distance between peaks of the light waveAmplitudeON OFFStructure of the Ear – read textAUDITION - HEARINGPerceiving Pitch, Volume, & LocationPerceiving Pitch: (highs vs. low sounds)2. Frequency theoryPerceiving volume: (loud vs. soft sounds)Perceiving Location: (where is that sound coming from?)What’s up with your own voice?Why?What is an illusion?How do we perceive depth?However…Three skills:Are ESP phenomenon reliable?Why do we believe?OUTLINE – Modules 10, 11, 12 13SENSATION1. Sensation vs. Perception2. Psychophysics3. Vision4. AuditionNOTE: Read about Touch, Taste, Smell, BalancePERCEPTION2. Organization and Interpretation- Some Perceptual Illusions- Gestalt Psychology- Constancy in Perception- Perceptual Set- Depth Perception- Perceptual Adaptation- Extra Sensory PerceptionExperiencing events: 2 StagesStage 1:SENSATION: The processes of :- Converting the physical world into a mental representation (transduction)- And relaying that information to the brain (conduction)EX: Transduction- Variations of light experience of color- Variations of are pressure experience of soundStage 2:PERCEPTIONthe processes of: - selection, organization and interpretation EX: - we can recognize the color GREEN- we can distinguish BACH from BRITNEY SPEARSPSYCHOPHYSICSWhat is it? The study of relationships between physical characteristics of stimuli (energy) and our psychological experience of themEX:Light brightnessSound volumePressure weightTaste sweetnessKey concepts:Absolute Thresholds – smallest magnitude of a stimulus that can be reliably discriminated from NO stimulus at least 50% of the timeDifference Threshold – minimum difference between two stimuli that a person can detect at least 50% of the time- just noticeable differencesEX:- detecting salt in your pasta- adjusting the sound on your iPod to the best and comfortable volumePSYCHOPHYSICSSignal Detection Theory- predicts how and when we detect the presence ofa stimulus amidst background stimulation- complex decision mechanisms are involved to determine if a stimulus existsBased on both:1. stimulus strength2. our experiencesPoint: - Absolute thresholds and Just noticeable differences are not fixedo Our sensitivity to a stimulus varies based on experiencesFactors that affect Absolute and Difference Thresholds:1) Chance variation – noise in the system influence sensitivity2) Stimulus intensityWeber’s Law – the greater the intensity of a stimulus, the larger the difference must be to detect a difference- They must differ by a constant proportion3) Sensory Adaptation – our sensitivity to an unchanging stimulus diminishesEX. getting into a hot tubWhen you get into a hot tub, it’s really hot that you can’t even get in. Once you’ve been in the hot tub, it doesn’t feel as hot anymoreVISIONQ: How do we turn light energy (physical stimulus) into vision (psychological experience)?2 aspects of light energy – light waves are crucial:Wavelength - The distance between peaks of the light wave- Corresponds to our sensation of colorR O Y G B I VShort wavelength violets and bluesLong wavelength reds and orangesAmplitude - The intensity of the light wave- Corresponds to our sensation of brightnessSmall amplitude dull colorsLarge amplitude bright colorsStructure of the EYE – read text1. Rods – cells in the periphery of the retina sensitive of light2. Cones – cells in the center of the retina (Forvea) sensitive to focus and color perceptionVISION: Two Major Theories of Color Vision1. Trichromatic theory (Young-Hemholtz)- Creation of colors – any color can be created by combining the red, green, and blue light in varying combinations- In our eyes, we have 3 kinds of cones:Cone 1: maximally sensitive to blueCone 2: maximally sensitive to greenCone 3: maximally sensitive to red- Experience of colors – results from mixing different levels of response from these 3 cone typesNote: Additive (light) vs. subtractive (paint) color mixingColorblindnessVISION: Two Major Theories of Color Vision2. Opponent process theory - opposing retinal processes enable color vision- neural impulses are antagonistic, a stimulus that elicits a response from the “red”, depresses a response of “green” ON OFFRed vs. GreenBlue vs. YellowWhite vs. Black- Explains Color After-ImagesEX: American Flag The brain knows that the world does not spontaneously change color When you stare at the white dot in the center of the flag, once you look at a white page, you see the actual color of theAmerican flagAUDITION - HEARINGQ: How do we turn variations in air pressure (physical stimulus) into our sense of hearing (psychological experience)?Two aspects are crucial:1. Frequency - The number of complete cycles per unit time (Hertz – cycle per second)- Corresponds to our psychological sensation of pitch2. Amplitude - The intensity of the wave- Corresponds to our psychological sensation of volumeStructure of the Ear – read textAUDITION - HEARINGPerceiving Pitch, Volume, & LocationPerceiving Pitch: (highs vs. low sounds)1. Place theory- Difference pitches produce responses on different places on the basilar membrane- Works well with high pitched sounds2. Frequency theory- Different pitches causes the basilar membrane, itself, to vibrate at different frequencies- Works well with low-pitched soundsPerceiving volume: (loud vs. soft sounds)No movement of the basilar membrane, but number of stimulated hair in the cellPerceiving Location: (where is that sound coming from?)Why do we have 2 ears?Left vs. RightUp vs. DownFront vs. BehindWhat’s up with your own voice?PERCEPTION – What is it?Def: The process by which we - select, - organize, and - interpret
View Full Document
Unlocking...