Cognition and Emotion

Transcription

1 Cognition and Emotion Week 3 - Class 1 27/11/2017 Joske Houtkamp Bachelor Course Information Science Utrecht University

2 ora/2017/07/31/how-does-yourdogs-range-of-emotionscompare-toyours/#56dca

3 Topics Sensation and Perception Sensation Perception Visual perception theories Perception and emotion Face perception & speech perception: self study for the exam Attention Top-down vs Bottomup processing Attention: selective attention, divided attention Attention theories Attention and emotion Saccades Assignment 2 3

4 Literature week 3 Matlin, M. (2014). Cognitive Psychology. Chapter 2, Recognizing Visual and Auditory Stimuli. pp (up to Face Perception) Chapter 3, Paying Attention, pp Chapter 4, Using Working Memory, pp

5 Sensation and perception 1. Sensation (gewaarwording) the process in which a sensory receptor is stimulated, producing nerve impulses that travel to the brain, which in turn interprets such impulses as a visual image, a sound, taste, odor, touch, or pain. Distal stimulus: e.g. an object Proximal stimulus: the information received on the receptors (e.g. visual receptor): e.g. The image of the object on the retina. 2. Perception (waarneming) the occurrence when the brain performs organization of information it obtains from the neural impulses, and then begins the process of translation and interpretation. It is a vital process that helps us rationalize or make sense of the information related to the physical stimulus. Interpretation of what is perceived. Visual /optical illusions reveal process

6 The sensory system Sebastian Stosskopf Sight (ophthalmoception), hearing (audioception), taste (gustaoception), smell (olfacoception or olfacception), and touch (tactioception) are the five traditionally recognized senses. (6: proprioception) 6

7 Vision (1) We see when electromagnetic waves/photons of 400 to 700 nm (10 14 en Hz) reach the eye just a very small range within the electromagnetic spectrum 7

8 Vision (2) Many animals, especially insects and birds, can see in the ultraviolet spectrum (10-400nm). Other animals (some snakes, bats, beetles) can sense heat (infrared) with organs that resemble the visual system. 8

9 Vision (3) what-do-dogs-and-cats-see/ es/28/mythbusting_dog_color_visi on.aspx 9

10 Audition (1) We hear : When mechanical waves between Hz. (frequency), created by vibrating objects, reach the ear. Below: low frequency, infrasound; above high frequency, ultrasound. 10

11 Audition (2) 11

12 Audition (3) 12

13 Somatosensation, Olfaction, Gustation Somatosensory system thermo(re)ception nociception (pain), touch (pressure, texture, vibration etc.) Olfaction Odorant molecules bind to specific sites on the olfactory receptors Gustation Substance in the mouth reacts chemically with taste receptor cells on taste buds Also: Body position: proprioception Chemical senses 13

14 Homunculus Humans only sense a small part of the information in their environment om/sensation+%26+perception The ABCs of Sensation Crash course Psychology #6 14

15 From sensation to perception Perception : The top-down way our brains organize and interpret that information and put it into context Cognition People s perceptions differ Sensation:the bottom-up process by which our senses receive and relay outside stimuli

16 Look at this image for a few seconds

17 What did you see?

18 The forest has eyes Bev Doolittle 18

19 Exercise Describe in one sentence what most strikes you in the next image. I see 19

20 Kees van Overveld -20-

21 Possible answers 1. Ik zie licht van de beamer teruggekaatst vanaf het projectiescherm 2. Ik zie een verdeling All these van lichte answers tinten are in possible het midden, bruinachtige naar interpretations de randen of what you are 3. Ik zie overwegend gladde kleurverdelingen, maar in het midden korrelig en aan de rand vlekkerig 4. Ik zie een paar lichte, afgeronde, symmetrische 2D vormen in het midden en een afgeronde driehoek linksonder 5. Ik zie een ruwweg bolronde vorm in het midden en een paar afgeplatte liggende 3D vormen daaronder 6. Ik zie een kopje cappuccino en een krant 7. Ik zie dat het kopje bijna vol is, en de krant is dichtgeslagen 8. Ik zie het zorgeloze begin van een veelbelovende vakantiedag in Italië 9... looking at Bron van dit voorbeeld: Kees van Overveld Van Licht tot Zicht

22 An image We tend to describe what we see as a number of objects But there are many levels on which we can describe this image Physical: illumination,colour, texture Shape: 2D en 3D shapes, features of shapes.. Object level: objects their features, relations, Meaning: message, feeling, 22

23 Light to meaning To make sense of the world it is necessary to organize incoming sensations into information which is meaningful: perceptual organisation. 23

24 Gestalt psychology Gestalt psychology helps to explain how we perceive visual stimuli. Humans perceive individual sensory stimuli as a meaningful whole. We tend to actively organize what we see, and understand the world in wholes and patterns. Gestalt (shape, form) is a global whole which is greater than the sum of its parts and determines its meaning. Max Wertheimer 24

25 Gestalt principles Rules of the organization of perceptual scenes Emergence 25

26 26

27 Figure ground articulation 27

28 Multistability/ ambiguous figure-ground relationship 28

29 Gestalt Laws of grouping (1) Prägnanz overall principle We tend to order our experience in a manner that is regular, orderly, symmetrical, and simple. Every stimulus is perceived in its most simple form. The basic principle the whole is greater than the sum of its parts. A number of rules or heuristics allow us to predict the interpretation of sensation, often called "gestalt laws". A combination of circles; not complex elements 29

30 Gestalt laws (2) Law of proximity When we perceive a collection of objects, we will see objects close to each other as forming a group. 30

31 Gestalt laws (3) Law of similarity Elements tend to be integrated into groups if they are similar to each other. 31

32 The human eye tends to build a relationship between similar elements within a design. Similarity can be achieved using basic elements such as shapes, colors, and size. 32

33 Gestalt laws (4) Law of continuity Elements of objects tend to be integrated into perceptual wholes if they are aligned within an object. In cases where there is an intersection between objects, two objects are perceived as two single uninterrupted entities. P. Van Denenberg, Jongens en Wetenschap content/uploads/sites/1896/2017/09/gestalt- 33 Theory.pdf

34 Gestalt laws (5) Law of closure We perceptually close up, or complete, objects that are not, in fact, complete. 34

35 Perception: illusions Escher in Het Paleis 35

36 Perception and reliability Which square is darker? A or B?

37 Perception and reliability Our brains complete the perception using expectations and experience.

38 Illusions : Müller-Lyer illusion Which line is longer?

39 Ambiguity 39

40 Leaning tower illusion Ponzo illusion Twin Towers of Pisa The visual system treats the three similar images as part of the same scene 40

41 McGurk effect Visual cues from the speaker s mouth help us interpret ambiguous sounds. McGurk effect: compromise between discrepant sources of information 41

42 Theories of visual object recognition Template matching, Feature analysis, Recognition-by-components 42

43 Captcha Completely Automated Public Turing-test to tell Computers and Humans Apart 43

44 Visual Object Recognition (1a) Template-matching model An incoming pattern is compared to a complete stored pattern 44

45 Visual Object Recognition (1b) Template-matching model - problems 45

46 Visual Object Recognition (2) Feature analysis theories A visual stimulus is composed of a small number of characteristics or components: distinctive features Distinctive features are compared to stored features for each letter Match features Match relation between features Select match with highest activation 46

47 Feature Analysis Theory Eleanor Gibson s research People require more time to decide if letters share many critical features Hubel and Wiesel's research Measure response of a single neuron to simple visual stimulus Depends on location on the retina and orientation Innate feature detectors help recognize certain features of letters and simple patterns 47

48 Visual Object Recognition 48

49 Recognition-by-Components Theory Irving Biederman : Recognition of 3D shapes A specific view of an object can be represented as an arrangement of simple 3-D shapes, geons 36 categories of geons proposed We recognize objects by a specific combination of geons: three should suffice to classify an object However: people recognize objects more quickly seen from standard viewpoint. 49

50 The Recognition-by-Components Theory: viewer centered approach Proposes that we store a small number of views of 3D objects (rather than one view). Other views require mental rotation, so more difficult. Both feature-analysis theory and the recognition-by-components theory can explain some portion of our skill in recognizing objects (but not all..). 50

51 Object Recognition: Context Theories explain recognition of isolated objects. How do knowledge and expectations aid recognition? 51

52 Bottom-up versus top-down processing Bottom-up processing Stimulus characteristics are important in recognition Very first part of visual processing may be bottomup Top-down processing Concepts, expectations and memory aid recognition Helps very rapid recognition, when the stimulus is registered for a short moment, is incomplete or ambiguous Both work together, for instance in reading: We do not first analyze features of letters, then letters, then words. Word superiority effect. We can identify a single letter more accurately and more rapidly when it appears in a meaningful word 52

53 Top-down processing: reading Read the text. What can you deduct about recognition of words? Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe. The context of a sentence facilitates the recognition of a word in a sentence. See discussion on 53

54 Final day of ski holiday 54

55 1: 10 AM Coffee 2: AM off piste skiing 3: lunch 4: looking for skis 5: confrontation with angry Germans 6: confusion 55

56 Checking video next day.. 56

57 Overactive top-down processing (1) Smart mistakes: overusing strategy top-down processing Change blindness (failing to detect a change in an object or scene) Top-down processing encourages us to assume that the basic meaning of the scene will remain stable We do not store a detailed representation of a scene

58 Overactive top-down processing (2) Inattentional blindness (a visible but unexpected object is not noticed; especially when the task is cognitively demanding) 58

59 Perception and Emotion Do moods and emotions influence what we perceive? Niedenthal &Setterlund: mood congruence. Happiness and sadness have emotion-congruent effects upon selective perception. Experiment: Mood induction by classical music (Vivaldi Mozart Rachmaninov, Mahler, ) Lexical decision task Strings of letters flashed on a screen; some words, in 5 categories: happy (e.g. delight) positive (calm), sad (weep), negative (injury) neutral (habit) Participants in a happy mood identified happy words quicker than sad words; participants in a sad mood identified sad words quicker than happy words Niedenthal, P. M., & Setterlund, J. B. H. M. B. (1997). Being happy and seeing''happy'': Emotional state mediates visual word recognition. Cognition & Emotion, 11(4),

60 Perception and Emotion Our current moods and feelings lead us to perceive emotioncongruent objects and events, thus prolonging our experience. Niedenthal & Setterlund: moods and emotions can redirect perception to objects and events that are relevant to current feelings. 60

61 Attention 61

62 What is attention? Trying to attend to everything at once is more than the cognitive processes can handle. Matlin (2010): Attention is a concentration of mental activity that allows you to take in a limited portion of the vast stream of information available from both your sensory world and your memory. Top-down processing: we pay attention to a specific stimulus Bottom-up processing: our attention is captured by an interesting stimulus in our environment NB: Matlin s theme 5: Many cognitive processes rely on both bottom-up and top-down processing 62

63 Attention Processes: divided attention Divided-attention task trying to pay attention to two or more simultaneous messages respond appropriately to each message speed and accuracy suffer Multitasking. walking and talking reading and IM (instant messaging) people may believe that they can multitask, but the research does not support this illusion; people perform faster and more accurately if they work on one task at a time. 63

64 Divided attention Multitasking: strain on attention, working memory, long-term memory. Extensive research on use of cell phones For instance in traffic Collet et al. (2009) Use of cell phones in simulated driving-task Reaction times were 20% slower than without the cell-phone conversation Strayer et al. (2003) Hands-free cell phone conversation Slower in applying brakes Inattentional blindness Also distracted by hearing cell phone conversation of passengers 64

65 Examples Attention for cell phone Texting in the car t=plm8ucpvzz-bf23tp5fv8fh_x-r794o4o3 65

66 Attention Processes: selective attention Selective Attention pay attention to certain kinds of information, while ignoring other ongoing information simplifies our lives people notice little about the irrelevant tasks. 66

67 Selective attention tasks Dichotic listening The Stroop Effect/Task Visual search Saccadic eye movements during reading 67

68 Selective attention task Dichotic Listening a selective-attention task one message presented to left ear and a different message presented to right ear shadow one of the messages (listen and repeat) people notice very little about the unattended message (for instance switch in language) early filter Want to try? Attend to the words in your left ear. Write down every word you hear that contains an m or a p without pausing or replaying the video. (No explanation or results) 68

69 Dichotic listening In general, people can process only one message at a time. However, people may process the unattended message if: 1. both messages are presented slowly 2. the task is not challenging 3. the meaning of the unattended message is immediately relevant: Cocktail party effect (Dichotic = in two separate parts) 69

70 Experiment Treisman Individuals follow message from one to other ear; so processing does occur (follow semantic content) Want to know more: Coursera, Introduction to Psychology, Steve Joorden /watch?v=_szpeqxmfbq 70

71 Selective attention task The Stroop Effect Name the colors in the rectangular patches below. Measure the amount of time it takes to go through this list five times. Record the time. 71

72 Selective attention task The Stroop Effect Say out loud the names of the ink colors, ignoring the meaning of the words. Measure the amount of time it takes to go through this list five times. Record that time. 72

73 Stroop effect Naming the colour of the ink takes longer when the word represents an incongruent colour; naming the colour of the patches is quick. Possible explanations: Connectionist/parallel distributed processing (PDP) approach ; two pathways are activated at the same time (ink colour and meaning of the word), interfere and negatively influence task performance. Adults have more practice in reading than naming colours; reading is automatic and involuntary. The more automatic process interferes with the less automatic process. 73

74 Selective attention task Visual search find a target in a visual display with numerous distractors Relevance: airport security, X-ray examination 74

75 Visual search Variables Influencing Visual Search Treisman studies 1. The isolated-feature/combined-feature effect searching for blue Xs; how much time does it take? 75

76 Visual search And now? 76

77 Visual search If the target differs from the irrelevant items in the display with respect to a simple feature such as colour, observers quickly detect the target. When the irrelevant items force you to search for a combination of features (both blue and X), visual search takes longer. 77

78 Visual search Variables Influencing Visual Search Treisman studies 2. The feature-present/feature-absent effect. searching for "circle with the line" or "circle without the line" People can typically locate a feature that is present more quickly than a feature that is absent. 78

79 Variables Influencing Visual Search Royden and colleagues (2001) People can quickly locate one moving target when it appears in a group of stationary distractors. In contrast, they take much longer to locate one stationary target when it appears in a group of moving distractors. It s easier to spot a movement-present object than a movement-absent object. 79

80 The neural basis of attentional control in visual search M. Eimer, 2014 Attention in the real world: toward understanding its neural basis M.V. Peelen, S.Kastner,

81 Saccades and Eye Tracking 81

82 Saccadic Eye Movements During Reading A selective-attention task Eye movements are important in looking, searching, driving, speaking, and reading Saccadic eye movement series of little jumps of the eye bring the center of the retina (fovea) over the words being read m/typography/ctfonts/w ordrecognition.aspx 82

83 Saccades In every saccade the eye moves forward ca 7-9 letters 83

84 Measuring Attention by Eye Tracking Faces draw attention to them on webpages Study 1: users are clearly drawn to faces when asked to look at pages and report what they remember 84 Are People Drawn to Faces on Webpages? T.Tullis, M.Siegel & M.Sun in: CHI 2009, Boston, Massachusetts, USA.

85 Eye tracking and task-performance Study 2 A Portfolio Summary page was modified to contain either a photo of a woman s face or no image Tasks had answers that could be found by reading information on the page Are People Drawn to Faces on Webpages? T.Tullis, M.Siegel & M.Sun in: CHI 2009, Boston, Massachusetts, 85 USA.

86 Eye tracking and task-performance Study 2: Contrary to expectation, a picture of a face in this context actually caused users to do worse on a task involving information adjacent to the face. 86

87 Explanations for Attention Neuroscience Research on Attention The Orienting Attention Network selecting information from sensory input attention required for visual search region: parietal lobe identified through studies of brain lesions Several regions of the brain are responsible for attention; here focus on cortex 87

88 Explanations for Attention Neuroscience Research on Attention The Executive Attention Network used when task features conflict (e.g. Stroop task) inhibits automatic responses to stimuli prefrontal cortex top-down control of attention academic skills (e.g., reading) meditation learning new ideas h?v=pnbr_nbfk9c 88

89 Bottom-up versus Top-down Bottom-up: data driven (guided by sensory features) Top-down: concept driven 89

90 Bottom-up versus top-down Not here! Not here! Look here Not here! Bottom-up attention 90

91 91

92 Early Theories for Attention Bottleneck theories narrow passageway information either passes through bottleneck or is lost too simple; underestimate flexibility information not lost at just one phase of the attention process 92

93 Feature-Integration Theory (Treisman) 1. Basic elements Distributed attention register features automatically parallel processing identify features simultaneously low-level processing Focused attention slower serial processing identify one object at a time complex objects identify which features belong together 93

94 Feature-integration theory 2. Research on the theory isolated features, distributed attention, pop out combined features: people need more time to find the target when there are a large number of distractors focused attention 94

95 Feature-Integration Theory 3. Current status of the theory Not really clear-cut categories. Distributed attention can occasionally resemble focused attention. Visual system may use distributed attention to quickly gather information about the general gist of a scene. 95

96 Attention and Emotion Anxiety narrows attention when people are afraid or anxious, they focus on what they are afraid of, or on safety; disregard for other things In lab experiments, for instance dichotic listening task: in state of fear attention is drawn away from the message they should track, to words presented to the other ear that are threatening ( death, blood ). (Mathews&MacLeod 1994). 96

97 Emotional Stroop task Naming the ink color of words with strong emotional significance (not per se negative) trouble ignoring emotional reactions Individuals with phobic disorder - slower on anxiety-arousing words than on control words victims of rape slower on words related to rape (Foa et al. 1991) people with social phobia slower with words on confidence, etc. suicide depression addiction eating disorders Matthews 1993: the slowing of colour naming is greatest with words that correspond to the subjects greatest anxiety 97

98 Emotional Stroop task Example 98

99 Explanation In fear or anxiety nervous system is switched into particular mode of processing Attentional bias/narrowing Attention is directed to cues in the environment about threat and safety Related to particular objects of a person s anxiety. 99

100 Propositions 1. Emotions are lower and more primitive ways of seeing the world. 2. Reason (ratio, the power of the mind to think and understand in a logical way) is better than emotions. Agree/disagree?

101 Example Eadweard Muybridge 9 April May 1904, English photographer important for pioneering work in photographic studies of motion, and early work in motion-picture projection; severe head injuries in a stagecoach crash, substantial injuries to the orbitofrontal cortex; led to eccentric behaviour afterwards, also lessened convential social inhibitions. "Muybridge race horse animated" by Eadweard Muybridge - The sequence is set to motion using these frames, originally taken from Eadweard Muybridge's Human and Animal Locomotion series, (plate 626, thoroughbred bay mare "Annie G." galloping) published 1887 by the University of Pennsylvania. Licensed under Public Domain via Commons - /media/file:muybridge_race_horse_animated.gif

102 Muybridge In 1874, Muybridge shot Major Harry Larkyns, possibly the real father of his son. Act of compulsive jealousy; not affected by other (social) emotions: compassion for his child, the victim, fear of consequences; societal morals, norms, conventions, etc. No longer rational 102

103 Are emotions rational? 1. Are emotions based on substantive beliefs, do they correspond to actual events in the world? Emotions are often the product of rather complex beliefs about real events in the world. 2. Do emotions help to function effectively in the (social) world? Emotions help to respond adaptively most of the time. 3. Do emotions guide cognitive processes such as perception, attention, memory and judgment in an organized way, or do they interfere and disrupt? Emotions have principled, systematic effects on cognitive processes and lead to reasonable judgments of the world. Emotions structure perception, direct attention, give preferential access to certain memories, bias judgments in ways that help the individual respond to the environment in valuable ways.

104 Emotions as prioritizers of thoughts, goals and actions (Simon, 1967) Emotions are necessary in any intelligent being; They are a solution to a general problem; They set the priorities among the many different goals that challenge individual at any given time; interrupt and prioritization principle : necessary for complex organisms such as humans Oatley, Keltner, Jenkins, Understanding Emotions, 2006

105 Example 1. Very simple animal behaviour is controlled by reflexes: e.g. tick. Reacts to stimuli (scent- drop from tree; warmthclimb to skin; vicinity of blood- burrow in skin and suck). Purely automatic reaction 2. A god : omniscient, omnipotent, has perfect model of the universe and no limitations of resources; could predict results of every actions even in complex universe. No role for emotions. 3. A human: in between. Oatley, Keltner, Jenkins, Understanding Emotions, 2006

106 Response to complexity Humans act with purpose in a complex world; Actions sometimes produce effects that were not anticipated. Our resources and knowledge are limited Should we continue, or change our actions and make new plans? For many (most) events we have no ready prepared response, skill, habit, or knowledge of the effect. When such events occur, our emotions signal them. Oatley, Keltner, Jenkins, Understanding Emotions, 2006

107 Emotions: bridges toward rationality Emotions prompt us, create a readiness to act; More effective than random actions or attempt to calculate outcomes. Cognitive science recognizes emotions as important for humans that have several motives and operate in a complex world; We cannot know everything and cannot control everything. Emotions are not irrational; when we have no fully rational solution (not enough knowledge), they offer bridges toward rationality. Oatley, Keltner, Jenkins, Understanding Emotions, 2006 A PowerPoint diagram meant to portray the complexity of American strategy in Afghanistan certainly succeeded in that aim. erpoint.html?_r=0

108 Signaling the nervous system (1) Emotions involve 2 kinds of signaling in the nervous system 1. Organisational 2. Informational Organisational signal Automatic, primary appraisal, no specific information about objects in the environment; Sets brain into mode of organisation, readiness to urge and act in line with specific basic emotion; Has a feeling tone but no other content; Source in or outside the body, in the environment; Automatic guess what to do next. Oatley, Keltner, Jenkins, Understanding Emotions, 2006

109 Signaling the nervous system (2) Informational signal Secondary appraisal Carries information to make mental models of events, their possible causes and implications. On the basis of these two kinds of signals we act in accordance with how we feel and with what we know; Normally 1 and 2 occur together to produce an emotional feeling with a consciously known cause and object; This helps individuals to respond to emergent opportunities and challenges in the environment. Oatley, Keltner, Jenkins, Understanding Emotions, 2006

110 Example: fear Organisational Interrupts ongoing action; Makes ready physiological mechanisms; Actions for flight or defensive fight; Urge to act; Directs attention to the environment to find signs of danger and safety. Moods are based on the same organisational signals but maintain the brain in a certain mode Informational part informs the brain about the thing we are frightened of (which may be insubstantial). Oatley, Keltner, Jenkins, Understanding Emotions, 2006

111 Effect of emotions on cognitive functioning How do emotions guide thought processes? Three perspectives 1. Emotion congruence 2. Feelings as information 3. Processing style Oatley, Keltner, Jenkins, Understanding Emotions, 2006

112 1 Emotion congruence Bower, 1981: Moods and emotions are associative networks in the mind. In memory pathways are devoted to each emotion in which past experiences, related concepts etc. are connected in a semantic network; experience emotion -> associations become available. -> learning of emotion congruent material (to current emotion) should be easier: material is more extensively integrated into active memory structures and more easily retrieved at time of recall. However, the process is more complex: also impact of tasks that the participants perform, the mood of the participants, participants personal characteristics. (Eich &Macauley). Oatley, Keltner, Jenkins, Understanding Emotions, 2006

113 2 Feelings as information Emotions themselves are informative when we make judgments. Emotions provide us with a rapid signal triggered by something in our environment ( e.g. anger: a state of injustice exists and needs to be changed). Many of the judgments we make are too complex to review all the relevant evidence e.g. how satisfied are you with the current government? Depends on many aspects: current environmental policy, taxes, health care, foreign policy, campaign promises etc. So complex that we often rely on a simpler assessments based on our current feelings. Humans can seldom act with full rationality, think through all relevant evidence and principles for sorting out that evidence and arrive at justified position. Emotions are heuristics, guesses that work better than chance a lot of the time, short cuts to making decisions or taking action. Oatley, Keltner, Jenkins, Understanding Emotions, 2006

114 Example feelings as information Schwarz and Clore: study of weather impact on emotional state of inhabitants in USA, Midwest. Question (phone): all things considered, how satisfied or dissatisfied are you with your life as a whole these days? 2 conditions: only rate life satisfaction first question on weather on location Results: participants who were not asked about the weather used their current mood as heuristics; the others realized the impact of the weather on their judgment. People use their emotions as heuristics when making judgments, except when they attribute those feelings to a specific source. Oatley, Keltner, Jenkins, Understanding Emotions, 2006

115 3 Processing style Different emotions induce qualitatively different forms of reasoning, of considering evidence and drawing conclusions. Positive mood facilitates use of existing knowledge structures (e.g. heuristics, stereotypes); Negative moods (sadness) facilitate more analytical thought and careful attention to situational details. (stereotypes are automatic, effort-saving tools for judging others; used more when emotions make individual lewss systematic, e.g. anger, happiness). Positive emotions broaden our thought repertoires, enable more creative and flexible thought, help individuals to form important bonds, and explore the environment; enhance creativity (experiment with candle task). Oatley, Keltner, Jenkins, Understanding Emotions, 2006

116 Assignment 2 Develop three design guidelines that support interface designers to consider user emotions, when users perception and attention are important for satisfactory use of the application. Emotions influence our perception and attention. Emotions direct and focus attention on important needs and goals; anxiety narrows attention. When people are afraid or anxious, they focus on what they are afraid of, or on safety, and disregard other things. Attention is greater to thoughts and stimuli that have relevance to the current mood state. According to Niedenthal & Setterlund, moods and emotions can redirect perception to objects and events that are relevant to current feelings. 116

117 To be continued See you on Wednesday 117