Sensation and Perception - PSY 101 - Michigan State University - PDF

PSY 101: Introductory Psychology Instructor: Anna Benedict (just this week :) Course Modality: In person Anthony 1281 Hi! (It’s me, your TA) EXAM 2 In person, Scantron exam on chapters 9 & 4 topics Mon 2/24 4:10 - 6:00pm in class Extra proctors coming in to monitor ch...

PSY 101: Introductory Psychology Instructor: Anna Benedict (just this week :) Course Modality: In person Anthony 1281 Hi! (It’s me, your TA) EXAM 2 In person, Scantron exam on chapters 9 & 4 topics Mon 2/24 4:10 - 6:00pm in class Extra proctors coming in to monitor cheating Review syllabus exam section for procedures Come prepared to follow all of those when prompted (remove smartwatches, put away all belongings, etc.) If you experience text anxiety, also practice relaxation techniques as you study - in other words, how to take the test, not just the content 3 Exam 1 Feedback So many d2l tools and resources to help you! Only 27% of students had looked at the ‘Study Tips for Psy 101’ doc Not just exam study tips! Tips for before, during, after class Don’t skip concepts you knew during class A lot of students got IVs, DVs, and control questions in Peardeck, Unit 1 A lot of students missed the IV question in Peardeck, on Monday Item-level statistics indicated some items weren’t as good I gave credit for multiple responses on some items - but I have higher expectations next time! Everyone got credit for a duplicate question (i.e., your answer was only evaluated once) I have higher expectations of myself next time!  Piaget’s theory of cognitive development in infancy relies heavily on an infant’s ______ Sensation and Perception Psy 101 Chapter 4  Sensation vs. Perception Sensation = how the outside world gets in Perception = how we construct internal representations of the world Sensation vs. Perception How do you perceive “The Dress”?? Sensation vs. Perception  Slightly more technical Basic Principles Sensation the process of receiving stimulus energies from the external environment and transforming them into neural energy Perception the process of organizing and interpreting sensory information so that it makes sense  Sensation and Perception Unified Information Processing System Bottom-Up Processing. initiated by sensory input. outside world’s influence on perception. Top-Down Processing. initiated by cognitive processing. internal/mental world’s influence on perception. expectations and prior understanding.  Sensation vs. Perception S&P usually blend into one continuous process… BUT - two distinct processes! ○ Illusions help illuminate S&P mechanisms Fraser’s Spiral  Sensation Sensory Receptors Specialized cells that selectively detect and transmit sensory information to the brain. Cells send signals via distinct neural pathways.  Sensation Photoreception (vision) Detection of light. Mechanoreception (touch) Detection of pressure, vibration, and movement. Chemoreception (smell and taste) Detection of chemical stimuli.  Sensation Synesthesia One sense induces an experience in another sense (“seeing” music and “tasting” color). Phantom Limb Pain © Paul Bradbury / age fotostock  Basic Principles: Sensory Thresholds Absolute threshold—the minimum stimulation necessary to detect physical stimulation half the time; that is, a particular light, sound, pressure, taste, or odor.  Absolute Threshold The absolute threshold for human vision equivalent to the amount of energy emitted by a single candle on a completely dark night from 30 miles away The absolute threshold for human hearing equivalent to the amount of energy emitted by the tick of a watch at 20 feet. Absolute Threshold Absolute Threshold https://cbcc.psy.msu.edu/join/ https://cbcc.psy.msu.edu/join/  Sensory Thresholds Noise Any stimulus that interferes with the perception of another stimulus. Richard Nowitz/Getty Images  Sensory Thresholds Difference Thresholds How much stimulus difference is necessary for detection? Just Noticeable Difference (JND). JND increases with stimulus magnitude. Low stimulus levels—small changes can be detected. High stimulus levels—small changes less noticeable.  Sensory Thresholds Weber’s Law To be perceived as different, two stimuli must differ by a constant proportion (%) - not a constant amount Constant x Intensity of Stimulus E.g. 0.10 x 40 = 4  Sensing the World: Critical Thinking Studies of the senses extend beyond basic physiological principles to understand the cultural, historical and political dimensions of the senses. New Research and Innovations Phillips Design Probe Program New Research and Innovations Phillips Design Probe Program  Psychophysics Psychophysics = is the study of the relationship Psychological Physical World between physical World characteristics of physical Light Brightness stimuli and our perceptual experiences of them, Sound Volume Signal detection theory = Pressure Weight predicts how and when we detect faint stimuli amid other Sugar Sweet background stimuli Contextual factors!  Signal Detection Theory In a signal detection task across a number of trials, stimuli of different intensities are presented. Test-taker indicates perception of the stimulus.  Signal Detection Task Observer Response Observer Response —“Yes, I see it” — “No, I don’t see it” Signal Hit (correct) Miss (mistake) Present Signal Correct rejection False alarm (mistake) Absent (correct)  Signal Detection Task Graph shows that the absolute threshold (correct 50% of time) for vision is about 12 lumens.  Factors Affecting Perception Attention Focusing awareness on a narrowed aspect of the environment  Selective Attention Selective attention = a mental “spotlight” that focuses conscious attention/awareness on a very limited aspect of all that you experience, while ignoring others. Selective attention allows you to concentrate on what you're trying to study and to filter out irrelevant sights and sounds. Selective Attention: Stroop Effect Failure of selection: “noise” stops our ability to focus attention on a specific aspect of a stimulus (specifically colors!)  Stroop Effect As fast as you can, name each color of ink used to print each rectangle below:  Stroop Effect As fast as you can, name the color of ink used to write each word below:  Factors Affecting Attention Attention can be attracted by novelty, size, color, movement, and ○ Emotional stimuli ○ Emotion-induced blindness ○ Inattentional blindness Did you miss it??  Subliminal Stimuli Subliminal stimuli = stimuli below the absolute threshold We are influenced by subliminal stimulation. Experimental studies can demonstrate detection of subliminal stimuli  Subliminal Stimuli Influence of information below the level of conscious awareness Priming: activating a particular concept or idea in memory so that the person is affected by that concept  Subliminal Stimuli Experimental studies – people more accurately identified the location of a geometric figure if it appeared where a naked photo was - even though they didn’t think they ‘saw’ it Subliminal Stimuli Subliminal Stimuli Subliminal Stimuli Sensing the World: Basic Principles Would you like beer mixed with some balsamic vinegar? Sensing the World: Basic Principles 80% Sensing the World: Basic Principles Told One Had Vinegar Sensing the World: Basic Principles Told One Had Vinegar 70% 30% Sensing the World: Basic Principles Told One Had Vinegar Blind Taste Test 70% 30% Sensing the World: Basic Principles Told One Had Vinegar Blind Taste Test 70% 41% 30% 59%  Perceptual Set Predisposition or readiness to perceive something in a particular way Top-down processing Perceptual sets influence what we hear, taste, feel, and see.  Perceptual Set Preschoolers thought French fries tasted better when presented in a McDonald’s bag Perceptual Set In-class Activity 4.1