Vision and HearingSeeingSlide 3Slide 4Slide 5PowerPoint PresentationVisual PerceptionGestalt PrinciplesPerceiving MotionPerceiving ColorSlide 11Perceiving DepthWhen we can’t see…HearingSlide 15Auditory PerceptionSlide 17Hearing ImpairmentVision and HearingVision and HearingSeeingSeeing•Visible light has a wavelength, and we Visible light has a wavelength, and we respond only to a narrow range of respond only to a narrow range of wavelengths of lightwavelengths of light•Our perception of an object’s brightness Our perception of an object’s brightness is influenced by the intensity of the is influenced by the intensity of the reflected light that reaches our eyesreflected light that reaches our eyes•HueHue–The color of lightThe color of light•Humans are mostly accustomed to Humans are mostly accustomed to red, green, and bluered, green, and blueSeeingSeeing•Front of the eyeballFront of the eyeball–Sclera:Sclera: the white of the eye the white of the eye–Iris:Iris: colored part of the eye colored part of the eye–Pupil:Pupil: circular hole through which light circular hole through which light enters the eyeenters the eye•Pupillary ReflexPupillary Reflex•DilationDilationSeeingSeeing•CorneaCornea–Part of the eye containing transparent cells Part of the eye containing transparent cells that focus light on the retinathat focus light on the retina•LensLens–Part of the eye that changed curvature to Part of the eye that changed curvature to keep images in focuskeep images in focus–Accommodation:Accommodation: changing the shape of the changing the shape of the lens to focus on objects near or farlens to focus on objects near or far•Myopia vs. HyperopiaMyopia vs. HyperopiaSeeingSeeing•Back of the eyeBack of the eye–Retina:Retina: membrane at the back of the eye membrane at the back of the eye responsible for converting light into neural activityresponsible for converting light into neural activity–Fovea:Fovea: central part of the retina responsible for central part of the retina responsible for sharpness of visionsharpness of vision•Retina contains two types of receptor cellsRetina contains two types of receptor cells–Rods:Rods: receptor cells in the retina allowing us to see receptor cells in the retina allowing us to see in low levels of lightin low levels of light–Cones: Cones: receptor cells in the retina allowing us to see receptor cells in the retina allowing us to see in colorin color•Optic NerveOptic Nerve–Nerve that travels from the retina to the brainNerve that travels from the retina to the brain–Optic ChiasmOptic ChiasmVisual PerceptionVisual Perception•Feature DetectionFeature Detection–Our ability to use certain minimal patterns to Our ability to use certain minimal patterns to identify objectsidentify objects–Feature Detection cells detect lines and Feature Detection cells detect lines and edgesedges•Gestalt PrinciplesGestalt Principles–Rules governing how we perceive objects as Rules governing how we perceive objects as whole within their overall contextwhole within their overall context–Our brains often provide missing information Our brains often provide missing information about outlinesabout outlinesGestalt PrinciplesGestalt Principles•ProximityProximity: objects physically close to each : objects physically close to each other tend to be perceived as unified other tend to be perceived as unified wholeswholes•SimilaritySimilarity: we see similar objects as : we see similar objects as comprising a wholecomprising a whole•ClosureClosure: when partial information is : when partial information is present, our brains fill in what is present, our brains fill in what is missingmissing•Figure-GroundFigure-GroundPerceiving MotionPerceiving Motion•Phi PhenomenonPhi Phenomenon–Illusory perception of movement produced Illusory perception of movement produced by the successive flashing of imagesby the successive flashing of images–Movie SignMovie SignPerceiving ColorPerceiving Color•Trichromatic TheoryTrichromatic Theory–Proposes that we base our color vision on Proposes that we base our color vision on three primary colors—blue, green, and redthree primary colors—blue, green, and red–Three kinds of cones sensitive to different Three kinds of cones sensitive to different wavelengths of lightwavelengths of light•Color BlindnessColor Blindness–MonochromatsMonochromats–DichromatsDichromats–TrichromatsTrichromatsPerceiving ColorPerceiving Color•Trichromatic theory accounts nicely for Trichromatic theory accounts nicely for how our three cone types work together how our three cone types work together to detect the full range of colorsto detect the full range of colors•Opponent Process TheoryOpponent Process Theory–Proposes that we perceive colors in terms of Proposes that we perceive colors in terms of three pairs of opponent cells: red or green, three pairs of opponent cells: red or green, blue or yellow, or block or white.blue or yellow, or block or white.–Afterimages illustrate opponent processingAfterimages illustrate opponent processing•Both theories may be partly correctBoth theories may be partly correctPerceiving DepthPerceiving Depth•Depth PerceptionDepth Perception–Ability to judge distance and three-Ability to judge distance and three-dimensional relationsdimensional relations•Monocular Depth CuesMonocular Depth Cues–Stimuli that enable us to judge depth using Stimuli that enable us to judge depth using only one eyeonly one eye–We can perceive three dimensions using only We can perceive three dimensions using only one eyeone eyeWhen we can’t see…When we can’t see…•BlindnessBlindness–Presence of vision less than or equal to 20/200Presence of vision less than or equal to 20/200•Motion BlindnessMotion Blindness–Patients cannot string together still images Patients cannot string together still images processed by their brains into the perception of processed by their brains into the perception of ongoing motionongoing motion•Visual AgnosiaVisual Agnosia–Deficit in perceiving objectsDeficit in perceiving objects•BlindsightBlindsight–Blind people who have experienced damage to a Blind people who have experienced damage to a specific area of their cortex can still make correct specific area of their cortex can still make correct guesses about the visual appearance of things guesses about the visual appearance of things around