3The cat saw the rat. The cat was the rat. .rat eht saw tac ehTThe cat saw the rat.The cat was the rat.
4Absolute ThresholdsThe level of sensory stimulation necessary for sensation to occur.Vision: Candle flame seen at 30 miles on a clear night.Hearing: Tick of a watch under quiet conditions at 20 feetTouch: A bee’s wing falling on you cheek from 1 centimeter (.4 inch) above.Smell: 1 drop of perfume diffused into a three room apartmentTaste: 1 teaspoon of sugar in 2 gallons of water.
5Difference ThresholdThe minimum difference that a person can detect between two stimuli.Just noticeable difference
6Signal Detection Theory Set of formulas and principles that predict when we will detect the presence of a faint stimulus amid background stimulation.Detection depends on qualities of the stimulus, the environment, and the person who is detecting.Three Variables:Stimulus Variable: how bright is the blip on the radar screenEnvironmental Variables: how much distracting noise is there in the room with the radar equipmentOrganismic Variables: is the operator properly trained and motivated.
7Diminished sensitivity as a result of constant simulation. Sensory AdaptationDiminished sensitivity as a result of constant simulation.
8Selective AttentionFocusing conscious awareness on a particular stimulus to the exclusion of others.
10The process of receiving information from the environment. SensationThe process of receiving information from the environment.
11Vision Dominates human senses. Light White Light: light as it originates from the sun or a bulb before it is broken into different frequencies.Color is seen because light bounces off objects at different frequencies.The eye has different receptors for different wave lengths.Wave lengths are based on the texture and solidity of what they hit.
12Electromagnetic Energy An energy spectrum that includes X-rays, radar, and radio waves, among other things. A small portion of this spectrum includes visible light energy, which can be detected by the eye.Two Characteristics Determines What We See:Length of the wave determines colorHue: The color of light, determined by the wavelength of light energyAmplitude of the wave (height) determines brightnessTaller is brighter.
14Parts of the EyeCornea: clear outer covering of the eye, behind which is a fluid.Iris: a colored circular muscle that opens and closes, forming larger and smaller circles to control the amount of light getting into the eye.Lens: the part of the eye that focuses an image on the retina.
15Parts of the Eye Pupil: The opening in the eye. Psychological factors that control iris muscles.Smaller when disgustedLarger whenReally like something or someoneAfraidStrong emotional arousalRetina: Back of the eye, which contains millions of receptors for light.
17Parts of the EyeRods: A visual receptor most sensitive to violet-purple wave length; very sensitive for nigh vision; “sees” only black and white.Cones: a visual receptor that responds during daylight; “”sees” color.Red rangeRods are on the side and cones in the middle of the retina.
18Differences Between the Cone and Rod Receptors ConesRodsNumber 6 millionLocation in Retina Center(fovea)Color Sensitive? YesSensitivity I dim light? LowAbility to detect sharp detail (acuity)? HighNumber 120 millionLocation in Retina Edge(periphery)Color Sensitive? NoSensitivity in dim Light? HighAbility to detect sharp detail (acuity)? Low
19Rods and ConesBipolar Cells: cells that form the middle layer in the retina. Bipolar cells gather information from the rods and cones and pass it on to the ganglion cells.Ganglion Cells: the top layer in the retina. Ganglion cells receive information from the bipolar cells and transmit it through their axon, which together form the optic nerve.Optic Nerve: the nerve that carries visual information from the eye to the occipital lobes of the brain.Blind Spot: the point at which the optic nerve travels through the retina to exit the eye. The lack of receptor rods and cones at this point creates a small blind spot.
20Color BlindnessInability to perceive certain colors, such as red and green.8% Males.05 % FemalesRed and Green cones do not workTruly color blind people are very rare
21AfterimageImage that remains after stimulation of the retina has ended. Cones not used fire to bring the visual system back in balance.
23Characteristics of Sound Pitch: How high or low a sound isTimbre: the complexity of a soundIntensity: how loud a sound isDecibels: a measure of how loud a sound is (its intensity)
24The Structure of the Ear Eardrum: a piece of skin stretched over the entrance to the ear; vibrates soundCochlea: A snail-shaped part of the ear, filled with fluid and small hairs that vibrate to incoming soundHair-cells: receptor cells for hearing found in the cochleaCilia: Hairlike extensions on cellsAuditory nerve: bundle of nerves carrying sound to the brain
26HearingSound waves go to the eardrum where vibration is started. This vibration causes the cochlea to vibrate where cilia are located. Cilia are tuned to receive different frequency movements of hare that cause electrical impulses to go through the auditory nerve to the brain.How strong and when a sound arrives at one ear is contrasted by the brain with the same thing from the other ear. Difference help us locate where sound is coming from
27Cutaneous Senses ( Touch) Cutaneous Receptors: Nerve receptors in the skin that respond to pressure, temperature, or painRecords pressureChanges in temperatureRemain active continuously to record an injury or poisonCan fire for hours and hours after accidents
28Smell Olfaction: the sense of smell Odor is hard to explain in words but when associated with emotional events. We never forget it.Odor can recreate strong emotional memories.Olfactory Bulb: units that receive odor molecules and communicate their nature to the brain
29SmellCilia in the nose collect molecules of odor which send and electrical impulse to the olfactory bulb which generates a “code” that is sent to the brain for interpretation.Smell is most critical in eating. More than tastePheromones: odor chemicals that communicate a messageAnimals have them. Not sure if humans do.
31TasteTaste receptors: chemical receptors on the tongue that decode molecules of food or drinks to identify themTypesSaltSweetSourBitterWork the same as cones
32Salt Necessary for survival Operates nerve cellsKeeps body chemistry in balanceUsed for muscle contractionChildren crave salt and it tampers with age until really old it re-opens
33Sugar (sweet) Necessary for energy Newborns can taste at one day old Too little sugar makes a person tremble, feel faint, and causes mental confusionThe desire for something sweet is built in
34Sourness and Bitterness Detectors Bitterness - Poisons - no odorSourness - Food gone bad - odor
35Body SensesKinesthetic sense: the system for sensing the position and movement of individual body parts.Vestibular sense: the system for sensing body orientation and balance, located in semicircular canals of the inner ear.
36PerceptionThe process of organizing and interpreting sensory informationBottom-up process: Information processing that focuses on the raw material entering through our eyes, ears, and other organs of sensation.Top-up Process: Information processing that focuses on other expectations and experiences I interpreting incoming sensory information
37GestaltThe “whole,” or the organizational patterns, that we tend to perceive. The Gestalt psychologists emphasized that the whole is greater than the sum of its parts.
41Grouping Principles: the perceptual tendency to organize stimuli into understandable groups Similarity: a perceptual cue that involves grouping like thins togetherProximity: a perceptual cue that involves grouping together things that are near one anotherClosure: the process of filling in the missing details of what is viewed
43The ability to see in three dimensions and judge distance Depth PerceptionThe ability to see in three dimensions and judge distance
44Example:Visual Cliff: an apparatus used to demonstrate depth perception
45Binocular Depth Cues: depth cues that require the use of both eyes Retinal Disparity: The difference between the image provided by the two retinasWhen the images are brought together in the brain, they provide the sense of depthConvergence: the tension in the eye muscles when the eyes track inward to focus on objects close to the viewerShort distance
46Monocular Depth Cues: Depth cues that require the use of only one eye Relative Size: If an object of known size appears large, it is probably close, and if an object appears small, it is probably distantRelative Motion: Apparent slowness indicates an object is distantInterposition: Closer objects partially obstruct the view of more distant objectsRelative Height: distant objects appear higher in a your field of vision that closer objects do
47Monocular Depth CuesTexture Gradient: how rough or smooth objects appearGradient: Different level of textures we can see at different distancesRelative Clarity: Distant objects are less clear than near by objects areLinear Perspective: Parallel lines seem to draw together in the distance
49Perceptual Constancies: perceiving the size, shape , and lightness of an object as unchanging, even as the retinal image of the object changes.Size Constancy: the ability to retain the size of an object regardless of where it is located.Shape Constancy: The ability to perceive an object as having the same shape regardless of the angle at which it is seenLightness Constancy: The ability to see an object as having a constant level of lightness no matter how the lighting conditions change
50A mental predisposition to perceive something one way and not another Perceptual SetA mental predisposition to perceive something one way and not anotherSchemas: concepts or mental frameworks that organize and interpret information