HP3502 Week 2 The Nature of Emotions PDF

H P 3 5 0 2 W E E K 2  All course materials, including but not limited to, lecture slides, handout and recordings, are for your own educational purposes only. All the contents of the materials are protected by cop...

H P 3 5 0 2 W E E K 2  All course materials, including but not limited to, lecture slides, handout and recordings, are for your own educational purposes only. All the contents of the materials are protected by copyright, trademark or other forms of proprietary rights. All rights, title and interest in the materials are owned by, licensed to or controlled by the University, unless otherwise expressly stated. The materials C O P Y R I G H T shall not be uploaded, reproduced, distributed, republished or transmitted in any form or by any means, in whole or in part, without written approval from the University. You are also not allowed to take any photograph, film, audio record or other means of capturing images or voice of any contents during lecture(s) and/or tutorial(s) and reproduce, distribute and/or transmit any form or by any means, in whole or in part, without the written permission from the University. Appropriate action(s) will be taken against you including but not limited to disciplinary proceeding and/or legal action if you are found to have committed any of the above or infringed the University’s copyright. HOUSEKEEPING Please set up your name tents Third edition of the KOJ text should be generally comparable with the fourth edition Some chapters may be reordered, with some minor changes in content Content (i.e., ideas, experiments, theories, etc.) that are not covered in the slides are not the focus of this course and are not examinable Focus on content that are introduced in the slides and refer to text for elaborations on concepts, ideas, etc. HOUSEKEEPING Submit reflection notes to Week 2 Reflection Notes folder Please keep your reflection notes within 100 words Upload your reflection notes as PDF or Word document (not text submission) before the deadline (i.e., end of Thursday) Refer to Week 1 slides (uploaded to NTUlearn) for tips on writing reflection notes Slots for group presentations will open at the end of this week Look out for Announcements on NTUlearn Indicate on the Google spreadsheet (a) the tutorial group/week that your team wish to present and (b) your team members Approach your TA if you do not have a group HOUSEKEEPING Present one article as a six- or seven-member team Two teams will present for each tutorial group (i.e., A or B) on Weeks 5, 8, & 10 Tutorial group A: 1530 – 1650 Tutorial group B: 1700 – 1820 Attend the tutorial group that your group will eventually present e.g., attend all group A tutorials in Week 5, 8, and 10 if your group will be presenting in one of the group A slots Tutorials will be held at LHS-TR+50 Note that attendance is compulsory for all three tutorials, even for the weeks that you are not presenting LEARNING OUTCOMES By the end of this class, you should be able to: 1. Outline the different historical approaches to understanding emotions 2. Appreciate the complexities of defining ‘emotion’ 3. Explicate the classic and modern theories of emotion 4. Understand the strengths and limitations of the different methods that affective scientists use to measure emotions OUTLINE 1. Approaches to understand emotions 2. What is an emotion? 3. Dominant theories of emotions 4. Measurement of emotion APPROACHES TO UNDERSTAND EMOTIONS P A R T 1 EVOLUTIONARY APPROACH Charles Darwin The Expression of the Emotions in Man and Animals (1872) Humans as descended from other species Humans are not only closer to animals than previously thought, but they are animals of a certain kind Two central ideas on emotions Universality and origins of human emotions EVOLUTIONARY APPROACH Universality of emotional expressions Similarity in emotional expressions in humans and other animals Emotional expressions originated from once- useful habits from our evolutionary past Based on reflex-like mechanisms Occur regardless of usefulness as triggered involuntarily in circumstances analogous to those that triggered the original habits e.g., tears that do not function to lubricate eyes when showing sadness, hair standing on end in fear and anger for no apparent purposes EVOLUTIONARY APPROACH Emotions link us to the past of our prehuman ancestors and to our own infancy Continuity of emotional expressions across developmental stages and across species e.g., sneering as a behavioral vestige of snarling and preparing to bite, human affection of hugging based on patterns of parents hugging young infants Emotions have useful functions and help to navigate social environments More on this in Week 3: Evolutionary & Cultural Perspectives PHYSIOLOGICAL APPROACH William James and Carl Lange Core of emotions attributed to the pattern of physiological changes e.g., trembling, perspiration, racing heartbeat, blushing, tingles in our spines Provide color and warmth to experience More on this in Week 2: The Nature of Emotions “If we fancy some strong emotion and then try to abstract from our consciousness of it all the feelings of its bodily symptoms, we find we have nothing left behind” (James, 1890, p. 451) PSYCHOANALYTIC APPROACH Sigmund Freud Certain events leave emotional scars that affect the rest of our lives Emotions are at the core of many mental illnesses Like Darwin, Freud thought that an emotion in the present could derive from one in early life PSYCHOANALYTIC APPROACH Led to the development of psychoanalysis Telling of a patient’s life story, therapist fills in gaps in story through interpretations, and the person receiving the therapy realizing something had been unconscious Often criticized by those who developed newer methods (e.g., cognitive behavior therapy) Emotional life of adulthood is influenced by relationships we had in childhood with parents or caregivers Theory of attachment by John Bowlby More on this in Week 7: Emotionality: Stability & Change PHILOSOPHICAL APPROACH Aristotle Emotions are evaluative judgments of events in the world We are responsible for our emotions because we are responsible for our beliefs Anger “may be defined as an impulse, accompanied by pain, to a conspicuous revenge for a conspicuous slight directed without justification towards what concerns oneself or towards what concerns one’s friends” (Aristotle, 1378b, 1.32) PHILOSOPHICAL APPROACH René Descartes Emotions arise in the mind and are dependent on how we evaluate events Closely connected to bodily changes (e.g., heart beating, blushing, tears) Emotions can be regulated, to some extent, by thoughts Emotions tell us what is important in our souls (conscious sense of self) in relation to our concerns and our identities Emotions serve important functions Usually functional but can be dysfunctional (e.g., thinking about someone we love versus dwelling on issues we cannot affect when we are overanxious) Affect not only our bodies but enable our actions and plans PHILOSOPHICAL APPROACH Epicureanism Live and enjoy simple pleasures (e.g., friendship) Rather than chasing after things that unnatural or ephemeral (e.g., wealth, fame) Lead to painful emotions (e.g., anger when someone frustrates one’s will, greed at wanting more, envy at someone having something we do not have) Shifting attention from irrational desires to worthwhile ones PHILOSOPHICAL APPROACH Stoicism Emotions derive from desires (e.g., yearning for fame and wealth) To free oneself from destructive emotions, one should extirpate desires First movements of emotions are automatic Cannot be avoided as they occur in the body Second movements of emotions are mental, involving judgement and decisions Involves thought and they are “up to us” NEUROSCIENTIFIC APPROACH Emotional regulation impaired among individuals who suffered frontal-lobe damage (e.g., Phineas Gage) Display inappropriate judgments (e.g., risk, morality, finances, etc.) Negative effect on interpersonal relationships (e.g., outbursts, sexual improprieties, etc.) Higher region of the brain (i.e., cortex) regulate subcortical regions where emotions reside Supported by brain lesion studies in animals where cerebral cortex severed from subcortical regions Display of intense emotions (e.g., strong anger with no provocation) Cortex also adds meaning to subcortical beginnings of emotion NEUROSCIENTIFIC APPROACH Brain regions involved in empathy network Similar brain regions activated both when one experiences pain and when one imagines loved ones experiencing pain (Singer et al., 2004) Anterior insular (i.e., tracks physical sensations and represents those sensations as conscious experiences of feeling) Anterior cingulate cortex (i.e., experiences of negative emotion and conflict, and motivates action) NEUROSCIENTIFIC APPROACH Differences in brain regions responsible for empathy and compassion (Singer et al., 2014) Empathy defined as experiencing an emotion similar to that of another person Elicited by observation or imagination of the other’s emotion Knowing that the other person is the source of one’s own emotion Compassion (or sympathy) Respond to others’ suffering with our own feelings of concern and the motivation to help that person Brain regions specific to compassion that enables nurturant behavior (e.g., periaqueductal gray) and reward- related processes (e.g., ventral tegmental area, nucleaus accumbens, orbitofrontal cortex) NEUROSCIENTIFIC APPROACH Evidence from split-brain patients Michael Gazzaniga Severed corpus callosum (i.e., nerve fibres that connects the both sides of the cortex) in split-brain patients Two sides of the brain are no longer in communication, but other processes remain intact (e.g., intelligence, personality, language, etc.) NEUROSCIENTIFIC APPROACH Empirical demonstration of how the two hemispheres work in making sense of emotions Frightening film presented to left visual field Experiences of fear generated in the right hemisphere Patient could not understand the source of her fear in linguistically functioning left hemisphere Narrating left hemisphere offered a story about how the experimenter was making her feel nervous MODERN THEORETICAL APPROACHES Role of appraisals in emotions Magda Arnold and Sylvan Tomkins Emotion relates self to object (Arnold & Gasson, 1954) Mediate our interior concerns with events and objects in the world Emotion arises when a person perceives, or think about, something that is relevant to a concern (i.e., something important to us) If we know what appraisals (or evaluations) are made of an event, we can predict what emotion is likely to occur If we know what emotion is currently being experienced, we can infer what appraisals are likely to have been made MODERN THEORETICAL APPROACHES Combinations of appraisals determine experienced emotions (Arnold & Gasson, 1954) Appraisals first involve judging the suitability of object (i.e., attraction or repulsion) Determine whether the emotion is positive or negative Subsequent distinctions involving difficulties in acting Give rise to specific emotions e.g., if object is suitable, present, and no difficulty attaining object, then emotion is love More on appraisal-related theories in Week 4: Cognition and Emotions MODERN THEORETICAL APPROACHES Emotions as the primary motivational system (Tomkins, 1962) Emotions as amplifiers of drives (e.g., hunger, thirst, sex) Human action and thought reflect interplay of motivational systems Each capable fulfilling certain function (e.g., eating, breathing) and potentially taking over the whole person Emotion prioritizes one particular drive signal over others e.g., upon seeing a snake, it is the fear that moves you away from MODERN THEORETICAL APPROACHES Emotions arise from social performances that we provide to fulfil social roles Erving Goffman and Arlie Hochschild Presentations of ourselves to each other creates social reality Derive sense of selfhood e.g., love and passion expected of new romantic partners; sympathy and filial love expected of new parents Engagement in roles enabled by enthusiasm and produces emotional rewards (e.g., pride or contentment in fulfilling the expectations of specific roles) MODERN THEORETICAL APPROACHES Performance can sometimes produce inner conflict Following rules and scripts but not being fully engaged Can result in anxiety, sadness, etc. Emotional labour Constructing and managing emotions to fulfil the requirements of a job (e.g., in service industries) Surface acting versus deep acting Surface actors tend to receive more negative responses from customers and more likely to suffer emotional exhaustion than do deep actors (Zhan et al., 2016) WHAT IS AN EMOTION? P A R T 2 DEFINING EMOTION Emotions are reactions to external and internal (i.e., concerns) events Reflects the relevance of the context to the person’s goals/concerns Distinguishes emotions from internal drives (e.g., hunger and thirst) Emotions are functional Gives priority or urgency to one goal over others Prepares and orients us toward having an effect on the environment Guiding and preparing us for quick, effective action to deal adaptively with concerns in the current context e.g., feeling fear  trying to escape, feeling angry at someone  striking back DEFINING EMOTION Emotions are locally rational Help us deal adaptively with context-specific concerns through possible courses of actions within social environments Emotions are relational Helps us form and engage in our relationships e.g., expressing sadness may invite help from others Reflects forms of social commitment e.g., when we love someone, we commit oneself to others and make their concerns our own; when we are angry, we commit ourselves to finding a resolution or a parting DEFINING EMOTION Several features of emotions Feelings (i.e., subjective changes) Appraisal (i.e., what the situation mean for our goals and concerns) Physiological changes (i.e., autonomic and neural arousal) Behavior (i.e., expressions of emotional experiences) TERMINOLOGY Affect Phenomena that have anything to do with emotions, moods, dispositions, and preferences Emotional episode State that lasts for a limited time, from seconds (e.g., facial expressions) and minutes (e.g., bodily responses) to hours (e.g., self-reported emotions) Typically has an intentional object e.g., anger usually involves a clear target TERMINOLOGY Mood State that may last for hours, days, or weeks, sometimes as a low-intensity background Objectless and free floating e.g., irritable mood does not involve a clear intentional object Sentiment is similar to mood as a prolonged emotional state but involves an object (e.g., love) Emotional disorders Last for weeks or months, sometimes for years Assessed by American Psychiatric Association’s Diagnostic and Statistical Manual (DSM) e.g., major depression includes depressed mood, or loss of interest or pleasure in most activities, that lasts at least two weeks (more on this in Week 9) TERMINOLOGY Personality traits “Trait” refers to long-lasting aspects of personality that span the entire lifetime e.g., agreeableness (e.g., love and compassion for others) Temperament (i.e., trait-like tendencies that we are born with; more on this in Week 7) Personality develops over the life span, and most of its traits have emotions at their core DOMINANT THEORIES OF EMOTIONS P A R T 3 JAMES-LANGE THEORY Attributed to William James and Carl Lange (1884/1885) Emotions are based on physiological responses to situations Bodily responses (e.g., trembling, perspiring, heart racing, etc.) as the antecedents of emotions Seeks to explain the feeling aspect of emotion e.g., drinking wine decreases body’s responses to stressor and subsequently reduces anxiety JAMES-LANGE THEORY Differences between commonsense view and James- Lange theory Commonsense view: Seeing a bear (event)  Fear (feeling)  Run away (behavior) J-L theory: Seeing a bear (event)  Run away (behavior)  Fear (feeling) However, do you automatically run away from a caged bear? JAMES-LANGE THEORY Unclear whether theory include appraisal (term was introduced in 1960s) But James did mention that assessment of situation results in physiological changes and subsequent feeling James-Lange theory, clarified: Event Cognition/Appraisal Physiological Changes & Behavior Feeling CANNON-BARD THEORY Walter Cannon and Philip Bard (1927, 1934) proposed an alternative theory to the James-Lange theory Appraisals, feelings, physiological changes and behaviours are causally independent of each other All these aspects occur at the same time e.g., seeing a bear elicits fear + running away, but fear does not cause you to run and running away does not increase your fear Early attempt at incorporating the cognitive aspects of emotion CANNON-BARD THEORY However, the theory cannot explain some observations Physiological changes sometimes precede feelings e.g., hearing a sudden loud noise  increased heart rate, sweating, etc.  feelings Emotional behaviours can potentially influence feelings (e.g., facial feedback hypothesis) Cannon-Bard theory: Cognition/Appraisal Event Feeling Physiological Changes & Behavior SCHACHTER-SINGER THEORY Proposed by Stanley Schachter and Jerome Singer (1962) Two-factor theory of emotion Undifferentiated autonomic arousal Assumes all emotions involve similar physiological responses but such responses cannot distinguish between different emotions Physiological arousal determines strength of emotional feeling Appraisal or explanation that one arrives at for the undifferentiated arousal  SCHACHTER-SINGER THEORY Specific emotion experienced is dependent on the information about situation Differences between emotions is determined by the cognitive (not physiological) aspect Empirical demonstration of the Schachter-Singer theory (1962) Schachter - Singer theory: Feeling Physiological Change ID Likely Event Cognition/Appraisal Behavior THEORETICAL COMPARISON James-Lange theory, clarified: Event Cognition/Appraisal Physiological Changes & Behavior Feeling Cannon-Bard theory: Cognition/Appraisal Event Feeling Physiological Changes & Behavior Schachter - Singer theory: Feeling Physiological Change ID Likely Event Cognition/Appraisal Behavior BASIC EMOTION THEORY Basic emotions are categorically distinct entities that evolved to handle prototypical threats and challenges in the human ancestral environment (Tooby & Cosmides, 2008) Paul Ekman and colleagues’ research on facial expressions Happiness, sadness, anger, fear, disgust, and surprise Other potential candidates Contempt, shame, guilt, interest, hope, pride, relief, frustration, love, awe, boredom, jealousy, regret, and embarrassment BASIC EMOTION THEORY Each basic emotion serves a unique adaptive function Fear evolved to help us escape threatening situations, disgust as an evolved emotional response to threats of contamination (e.g., rotting food, parasites, etc.) Basic emotions coordinate different aspects of emotions (i.e., appraisal, physiology, subjective feelings, behaviours) Produce a coherent package of responses that helps to effectively deal with the situation e.g., fear response comprises heightened visual acuity and attention, increased fight-flight sympathetic nervous activation, increased tension in skeletal muscles, etc. Responses can occur independently in other situations, but fear pulls them together so that you have the best chance of escaping BASIC EMOTION THEORY All aspects of emotions should hang together However, objective aspects of emotions (e.g., physiological changes, facial expressions) are emphasized as they reflect evolved, functional responses Less emphasis on subjective feelings Most closely aligned with (but not identical to) James- Lange theory Conceptual categories of emotions reflect naturally occurring human experiences Basic emotions should be universal among humans and, to a certain extent, other species as well Acknowledges that different culture-specific concepts exist, but some categories are inherent among all humans BASIC EMOTION THEORY Each basic emotion should be physiologically distinct Involves particular profiles of bodily effects and/or activation of unique brain networks Individuals should have built-in way of expressing basic emotions (e.g., facial expressions, tone of voice, etc.) Basic emotions should be evident in early life Difficulties in determining how early an emotion must occur to be considered basic Newborns show generic distress and pleasure; smiling and frowning emerge within 2 or 3 months; while fear expressions become distinct from distress by 6 months As opposed to nostalgia and patriotism which emerge in adulthood (if at all) More on this in Week 7: Emotionality, Stability, & Change CORE AFFECT & PSYCHOLOGICAL CONSTRUCTION Models that categorize emotional terms along dimensions or factors Core affect/psychological construction or constructivist approach Emphasize the feeling aspect of emotions Feelings are mainly defined in terms of valence (i.e., positive and negative) and degree of arousal or activation Emotional feelings are best described in terms of continuous dimensions (rather than discrete categories) CORE AFFECT & PSYCHOLOGICAL CONSTRUCTION Descendent of the Schachter-Singer theory Physiological arousal is too general and undifferentiated to distinguish consistently among basic emotions Unlike S-S theory, the constructivist approach does not assume that physiological arousal is necessary to label one’s emotions CORE AFFECT & PSYCHOLOGICAL CONSTRUCTION Categories of emotional experience created by psychological construction Mental concepts that we use to organize our experience of the world Emotional concepts (e.g., anger) that are associated with specific situations (e.g., being insulted), physiological changes (e.g., face turning red), behaviours (e.g., yelling at offender) represent stories that make sense of human feelings CORE AFFECT & PSYCHOLOGICAL CONSTRUCTION Formation of emotional concepts Process begins we when first learn emotional labels from parent or caregiver Associations of words with experiences reinforced with every subsequent instance the labels are encountered (e.g., on our own, by others, in films, books etc.) Over time, words are linked to rich network of experiences, leading to prototype of emotional concept CORE AFFECT & PSYCHOLOGICAL CONSTRUCTION Circumplex model (Russell, 2003) Categorize emotional words according to pleasantness (or valence) and arousal (i.e., core affect) e.g., excited as a combination of pleasure and high arousal Positive and negative affect modelled as a bipolar univariate construct Studies based on other languages produced similar results (e.g., Chinese, Korean) CORE AFFECT & PSYCHOLOGICAL CONSTRUCTION Positive and negative emotions can be modelled as unipolar bivariate constructs Evaluations of positive and negative affect are separable, rather than opposite ends of a single dimension An event can be good and bad at the same time Two-factor structure of affect (Watson & Tellegen, 1985) Evaluative space model (Cacioppo et al., 1997) CORE AFFECT & PSYCHOLOGICAL CONSTRUCTION Evidence for the experiencing both positive and negative emotions Participants reported feeling both happy and sad after watching film clips, moving out of their dominatories, or graduating from college (Larsen et al., 2001) See also Week 8 Student Presentation reading (Ersner- Hershfield et al., 2008) APPRAISAL THEORIES Appraisal theories emphasize the role of cognitive evaluations or appraisal in emotional experiences Component process model as an example of an appraisal theory Other appraisal models/theories to be introduced in Week 4: Cognition and Emotions Appraisals in CPM are dimensional (Scherer, 2009) Novelty, pleasantness, expectedness, certainty, goal conduciveness, need for change, and controllability e.g., experience of disgust upon seeing a cockroach: moderately novel, unpleasant and highly unexpected, certain that it is a cockroach, in conflict with goals (you don’t want to see one), high or low controllability (dealing with cockroach or running away) COMPONENT PROCESS MODEL Physiological and behavioural responses to emotional events are real and predictable Determined by combined effects of individual appraisal dimensions, rather than a predetermined package corresponding to a basic emotion category Sequential unfolding of different appraisals (not all at once) e.g., facial expression of anger as a result of four appraisals, each corresponding to different aspects of the situation COMPONENT PROCESS MODEL Comparison of CPM with the basic emotion theory Multiple aspects of emotions cohere together in similar ways across cultures Modal emotions resemble basic emotions and likely reflect prototypical threats and opportunities faced throughout evolution However, various instances of the same general emotion may not look the same depending on underlying appraisals e.g., certain parts of anger can arise without the full emotional profile COMPONENT PROCESS MODEL Comparison of CPM with the constructivist approach Appraisal dimensions can be combined in various ways that do not fit neatly into a basic emotion category Emotion space is better described in terms of dimensions than categories Allows for a wide variety of non-prototypical emotions (e.g., awe, poignancy, etc.) MEASUREMENT OF EMOTION P A R T 4 INDUCING EMOTIONS Emotional induction allows us to study cause-and-effect relationships Experimentally manipulate emotional experiences Recollection Recall a time when a strong emotion was experienced and then talk or write about the experience Vignettes Read and vividly imagine themselves in a story (vignettes) designed to evoke emotional responses INDUCING EMOTIONS Affective materials Pictures, films, music Manipulating situations Giving small gifts (e.g., cookies), complimenting participants on their “creativity” on a task, giving a speech to a cold audience (Isen et al., 1987; Taylor et al., 2010) Posing specific facial expressions Participants are given muscle-by-muscle instructions to generate a facial expression of an emotion ADVANTAGES OF EMOTION ELICITATION METHODS Face valid with emotional meaning which most people can agree on Most methods can target specific emotion states (e.g., fear, pride) Relatively reliable and validated databases of pictures and films that elicit specific emotions (e.g., International Affective Picture System) Certain methods are ecologically valid e.g., methods that manipulate situations in the real world DISADVANTAGES OF EMOTION ELICITATION METHODS Laboratory-based techniques may lack ecological validity May not fully represent the range or intensity of everyday emotions e.g., watching a film clip of a person acting offensively is not the same as being insulted by someone; methods that rely on vignettes or recollection do not involve a real and present event; is the feeling of anger from making an angry expression identical to the anger felt in real-life situations? DISADVANTAGES OF EMOTION ELICITATION METHODS Methods differ in effectiveness in eliciting emotions Listening to music may not always elicit emotions effectively, while film clips are typically more dynamic and realistic Participants differ in the intensity of emotional memories recalled Certain methods may lack specificity in generating the target emotion Techniques that manipulate situations may elicit various emotions and people may respond to them differently Corresponding effects from posing facial expressions may be caused by the physical effort of exerting muscle movements s(and not necessarily related to the intended emotions) MEASUREMENT CONSIDERATIONS Reliability Consistency or repeatability of its scores, ranging from 0 to 1 e.g., questionnaire could have low reliability if items are worded in a confusing way Validity Accurately measuring what it is supposed to measure Do the items or content should match the stated purposes in a reasonably obvious way? Do all the subcomponents of the measure (e.g., items in a questionnaire, change in heart rate and blood pressure) correlate positively with one another? Do scores on the measure (e.g., scores on an anger scale/task) accurately predict some conceptually related outcome (e.g., frequency of getting into fights)? SELF-REPORT MEASURES Assesses the feeling aspect of emotion Cross-sectional or longitudinal (e.g., day reconstruction method, experience-sampling method) Convenient and easy to collect Rate specific emotions on a scale (e.g., 1 = not at all, 7 = very much so) Imprecision due to differing standards between individuals e.g., is your rating of 5 for nervousness the same as someone else’s 5 or from your own 5 at some other time? SELF-REPORT MEASURES Difficult to compare individuals who speak different languages Meaning may be lost in translation Likewise, certain populations may have difficulty understanding language (e.g., infants, brain-damaged individuals, nonhuman animals, etc.) Self-reports sometimes conflict with other measures of emotion (e.g., physiological and behavioral measures) However, within-subject changes in self-reported affect correspond to physiological changes (e.g., skin conductance, cardiovascular activation) (Mauss et al., 2005) PHYSIOLOGICAL MEASURES Assesses the physiological aspect of emotion The way the body prepares for action (i.e., action tendency) Sympathetic nervous system prepares the body for fight-or-flight situations (e.g., heart beating faster, hands start to sweat, stomach tightens up, etc.) Parasympathetic nervous system facilitates growth and increases maintenance functions that conserve energy for later use Cardiovascular arousal (e.g., heart rate), hormones (e.g., cortisol), skin conductance, electroencephalography (EEG), functional magnetic resonance imaging (fMRI) PHYSIOLOGICAL MEASURES May represent a more objective method than self-reports (e.g., definition of heart rate is unambiguous, unlike scores on a questionnaire) EEG (i.e., measures changes in electrical activity around the scalp) Renders precise timing of emotional experiences Can be detected within a split second after exposure to emotional stimulus fMRI (i.e., measures brain activity based on changes in oxygen uptake) Provides precise location of changes in brain activity with greater spatial accuracy than EEG PHYSIOLOGICAL MEASURES May be expensive and uncomfortable for participants (e.g., fMRI requires participants to lie motionless in a very noisy device) May lack ecological validity (e.g., fMRI settings do not reflect real-life situations) Physiological data differ widely across individuals Due to biological differences from person to person More informative to look at effects of emotions in terms of changes from baseline PHYSIOLOGICAL MEASURES Interpretative difficulties Some measures are unable to differentiate between specific emotions (e.g., elevated heart rate changes for both elation and anxiety) Physiological changes can be the result of extraneous factors (e.g., sneezing) Potential ambiguity in the interpretation of results (e.g., amygdala activation in response to a picture of a spider could mean fear or animal detection) BEHAVIOURAL MEASURES Assess the behavioral aspect of emotions Contractions of facial muscles (e.g., lowering of eyebrows, squinting of eyes, tightening of lips during anger) Useful for studying emotions in certain populations (e.g., nonhuman animals, infants, etc.) Facial Action Coding System (Ekman & Friesen, 1984) Record which facial muscles contract and for long and how intensely BEHAVIOURAL MEASURES Behavioural expressions may not reflect experienced emotions Individuals can fake or conceal their emotions (e.g., expressive suppression) Coding facial expressive is extremely time intensive Specific muscle movements (i.e., action units; e.g., eyes widening, raising of eyebrows, etc.) are quick and subtle Requires training and patience to distinguish all movements correctly Ambiguity of facial expressions Certain expressions are less clearcut than others and generally require agreement among raters  H P 3 5 0 2 E V O L U T I O N A R Y & C U L T U R A L P E R S P E C T I V E N E S S