P a g e 1 Chapter 3 Sensation and Perception A Sensation the activation of receptors in the various sense organs Sensory receptors specialized forms of neurons within the sense organs 2 17 2010 I Sensation 1 2 Sense organs a b c d e eyes ears nose skin taste buds Everything up to the neural impulses is sensory information Once it reaches the brain it becomes perception B Sensory Thresholds when we notice something happened Just noticeable difference JND or the difference threshold the 1 smallest difference between two stimuli that is detectable 50 percent of the time P a g e 2 Weber s Law JND is a constant proportion of the original stimulus a intensity One of very few actual laws in psychology Taste difference is 20 weight difference is 0 2 loudness difference is 10 Absolute threshold the smallest amount of energy needed for a person to 2 consciously detect a stimulus 50 percent of the time it is present How bright of a light how loud of a sound how intense a flavor before you notice i i Sight Hearing Smell Taste Touch EXAMPLES OF ABSOLUTE THRESHOLDS A candle flame at 30 miles on a clear dark night The tick of a watch 20 feet away in a quiet room One drop of perfume diffused throughout a three room apartment One teaspoon of sugar in two gallons of water A bee s wing falling on the cheek from 1 centimeter above 3 Subliminal sensation Subliminal stimuli stimuli that are below the level of conscious a awareness below absolute threshold i ii iii Just strong enough to activate the sensory receptors but not strong enough for people to be consciously aware of them Sub below Limen threshold Subliminal perception process by which stimuli below the threshold b of awareness act upon the unconscious mind influencing motivation and attitude but not behavior C Habituation and Sensory Adaptation Habituation bored tendency of the brain to stop attending to constant 1 unchanging information a Daydreaming in class is an example b This is the reason babies tend to pay more attention to new things than things they have seen many times Sensory adaptation tendency of sensory receptor cells to become less 2 responsive to a stimulus that is unchanging a The sense of smell adapts the quickest Microsaccades constant movement of the eyes tiny little vibrations that 3 people do not notice consciously prevents sensory adaptation to visual stimuli P a g e 3 II The Science of Seeing A The Electromagnetic Spectrum The Visible Spectrum The wavelengths can see are only a small part of 1 the electromagnetic spectrum a Long waves 700 nanometers seen as red b Short waves 400 nanometers seen as violet c Longer waves are considered hot colors because they are closer to the waves that can burn Infrared etc Psychological Aspects of Light can quantify measure the B psychological aspects of light Brightness determined by the amplitude of the wave how big is the wave 1 The bigger the wave the brighter it will appear 2 Color or hue is determined by the length of the wave a Long wavelengths are found at the red end of the visible spectrum whereas shorter wavelengths are found at the blue end Saturation refers to the purity of the color people see mixing in black or 3 gray would also lessen the saturation C Structure of the Eye P a g e 4 1 Cornea initial focus clear membrane that covers the surface of the eye protects the eye and is the structure that focuses most of the light coming into the eye Radial keratotomy vision improving technique that makes small a incisions in the cornea to change the focus in the eye Aqueous Humor next visual layer clear watery fluid that is continually 2 replenished and supplies nourishment to the eye Pupil hole through which light from the visual image enters the interior of 3 the eye Iris round muscle the colored part of the eye in which the pupil is 4 located can change the size of the pupil letting more or less light into the eye helps focus the image Lens another clear structure behind the iris suspended by muscles 5 finishes the focusing process begun by the cornea Visual accommodation the change in the thickness of the lens as a the eye focuses on objects that are far away or close 2 22 10 6 Retina a Photoreceptors i Rods ii Cones b Blind Spot P a g e 5 7 Common Visual Problems a Nearsightedness myopia b Farsightedness hyperopia c Presbyopia d Astigmatism Dark Adaptation Light Adaptation D Color Vision Trichromatic Theory Afterimages Opponent process Theory Color Blindness a Monochrome colorblindness b Red Green colorblindness c Sex linked inheritance d Ishihara Test 8 9 1 2 3 4 P a g e 6 III The Hearing Sense A Perception of Sound Physical and Psychological Properties Wavelength Frequency Pitch Hertz cycles per second Amplitude Loudness Purity Timbre richness B Structure of the Ear 1 2 3 4 1 2 3 4 5 6 1 2 Auditory Canal Eardrum Ossicles Cochlea Organ of Corti Auditory Nerve Pitch Place Theory C Theories of Pitch P a g e 7 3 Frequency Theory 4 Volley Principle D Hearing Impairments 1 Conduction Impairment 2 Nerve Impairment a Cochlear Implant IV Taste A Taste Buds B Gustation Gustatory Sense C Five Basic Tastes 1 2 3 4 P a g e 8 5 V Smell A B Olfaction Olfactory Sense Olfactory Bulbs C 1000 olfactory receptors VI Somesthetic Senses A Skin Senses 1 Sensory Receptors in Skin 2 Gate control Theory B Kinesthetic Sense 1 Proprioceptors C Vestibular Senses 1 2 Otolith Organs Semicircular Canals P a g e 9 VII Perception and Constancies A Perception Size Constancy Shape Constancy Brightness Constancy B Gestalt Principles Figure ground Reversible Figures 1 2 3 1 2 3 4 5 6 7 1 2 Similarity Proximity Closure Continuity Contiguity C Development of Perception Depth perception Visual Depth Perception The Visual Cliff 3 Monocular Depth Cues Pictorial and Body Cues P a g e 10 a Aerial Perspective b Texture Gradient c Motion Parallax d Accommodation 1 2 1 2 3 4 Binocular Depth Cues Body Cues a Convergence b Binocular Disparity D Perceptual Illusions Illusion Hallucination E Factors That Influence Perception Perceptual Set Expectancy Top Down Processing Bottom up Processing F Applying Psychology 1 Extrasensory Perception a Telepathy b Clairvoyance P a g e 11 c Precognition 2 Parapsychology
View Full Document
Unlocking...