CH 4 – Categorical Approaches to the Structure of Affect Emotions as discrete categories -­‐ many scientists view emotions as instances of discrete categories (e.g. anger, fear, sadness) -­‐ assumption of basic or primary emotions (across cultures and species) -­‐ ‘basic emotions’ shouldn’t be taken too literally: scientists are usually referring to a group of related affective states -­‐ = emotion family à each emotion family has a common theme (commonalities in antecedents, physiological responses, expression, action patterns, appraisal processes) + a number of variations (individual differences in biology, genes, learning experience, contexts) What do we mean by basic emotions? -­‐ ‘basic’ (fundamental, important function) means that the emotion is critical for the survival of: -­‐ 1. The species – biological criterion -­‐ 2. The society – social criterion -­‐ 3. The self – psychological criterion -­‐ Biological criterion: most commonly used in emotion science (Darwin etc.) -­‐ à biology was thought to be more fundamental than the other stuff -­‐ BUT: Biological mechanisms only set loose constraints to behavior -­‐ Culturally based concept: the particular form of emotion is largely constructed by social factors -­‐ à there are different emotions in different cultures (e.g. Liget = the feeling of exhilaration when taking a head among head-­‐hunting people of the Philippines :’D) -­‐ à thus many emotions are basic in a social but not in a biological sense! -­‐ -­‐ Notion of emotional categories: most dominant approach in emotion science -­‐ à basic emotions involve internal bodily activities, expressive capacities due to evolved neural structures -­‐ + each basic emotion has unique feeling -­‐ central assumption: at least some emotions are products of evolution (strong biological basis) -­‐ For a brief overview of some influential approaches assuming discrete emotions: Box 4.1, p. 86-­‐87 Criteria for basic emotions -­‐ One central idea behind categorical approach: when an emotion is triggeredà set of easily recognizable behavioral and physiological responses is produced -­‐ Responses are coordinated in time and correlate in intensity -­‐ P.88, figure 4.2: schematic model of emotion (by Levenson) -­‐
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à emotion is activated by an environmental event or appraisal of this event à activation of specific neural circuit à activation of behavioral and physiological responses Not clear how direct the association between neural circuit activation and ‘feeling’ is! There are several lists of ‘basic’ emotionsà theorists use different criteria Most theorists agree on happiness, fear, anger, disgust and sadness Ekman outlined 3 criteria for distinguishing different basic emotions, 6 criteria to establish whether an emotion is basic à p.88, table 4.1 Overview of empirical evidence for discrete emotions Distinctive signals -­‐ Expressing emotions by various signals (e.g. posture, sound, actions) -­‐ Emotions that are opposites show opposing signals/expressions -­‐ Tomkins: each emotion has different specific response pattern due to innate neuromotor program Recognizing different facial expressions -­‐ high agreement of people when matching labels to photographs of emotional facial expressions -­‐ also in other cultures -­‐ when testing in isolated ‘stone age’ culture: also high agreements (not influenced by western movies) -­‐ à evidence for 6 basic emotions: happiness, surprise, fear, sadness, anger, disgust -­‐ BUT: presenting people with label + forced choice may have inflated outcome -­‐ Ortony and Turner: maybe the facial expressions themselves are not universal but some components of them are -­‐ à no research on that yet Recognizing emotional prosody and vocalization -­‐ testing recognition of emotional vocalization: actor reads out standard phrases or nonsense syllables in a particular emotional tone -­‐ à participant has to indicate the emotion by matching standard labels to the tone -­‐ Agreement about 60% -­‐ Same problem of forced choice and limited labels -­‐ When more variants of each emotion family are expressed: approx. 55% accuracy -­‐ à still high above chance (would be 10%) -­‐ few cross-­‐cultural studies -­‐ identification of emotion decreases a the similarity in language from the actors’ native language gets more distant à portrayal of emotion by the voice is probably influenced by culture -­‐ but still striking similarity in the patterns of errors that occur across different languages -­‐ à supports universality of vocalization -­‐ Emotional prosody: enhances neural activity in auditory cortex -­‐
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Angry prosody: superior temporal sulcus (bilaterally) à sensory brain response due to threat-­‐info Neural mechanism to prioritize emotionally significant stimuli Role of social interaction may be importantà e.g. hearing requirements of receiver influence how the sender sends the signal Very difficult to include dynamic social interaction and rapidly changing expressions and intonations in experiments! Distinctive physiology Evidence for emotion-­‐specific autonomic nervous system activation -­‐ idea that distinctive emotions are accompanied by a distinctive pattern of physiological activity -­‐ ANS is responsible for energy metabolism, tissue repair etc. -­‐ Energy requirements are likely to be the same across emotionsà so same ANS response? -­‐ Levenson: clear differences in ANSà ANS provides support for behavioral demands (+ regulating homeostasis) -­‐ If function of emotions is to organize response to some environmental demand, incl. mobilization of specific behavior, specific patterns of activation are necessary -­‐ Different patterns of ANS for each emotion were found à patterns may be universal (cross-­‐cultural findings) -­‐ Other research finds only weak evidence -­‐ Explanation: ANS activation is primarily related to motor outputs rather than to other aspects of emotions -­‐ Patterns of ANS may have been selected because they serve specific motor responses (flight, fight, freezing…)à became adaptive for certain emotions -­‐ à that would mean that ANS might not be emotion-­‐specific if the motor-­‐response is not required for survivalà happiness, sadness Distinctive neural circuits -­‐ identifying basic emotions by specifying brain circuits Animal research -­‐ Panksepp: affective processes arise from subcortical emotional action systems -­‐ à shared by all mammals -­‐ à unique feeling or experience à neurobiological animal studies -­‐ but doubt that some animals have feelings at all, some argue that feelings are implemented by cortical areas or that feelings are easier studied in humans Panksepp’s approach: emotional action systems -­‐ Functioning of neurotransmitter systems lies at the heart of emotional action systems -­‐ Neurotransmitter categories: amino acids, amines, peptides (table 4.2, p.97) -­‐
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We should study animals under fairly naturalistic conditions so that neurotransmitters for specific affective systems can be identified These neurotransmitters can then be manipulated in humansà observe affective changes For principles of neurotransmission: Box 4.2., p.97 Affective processes in the brain: 3 general categories (differ in level of complexity) Brain stem (lower functions, reflexive affects) à mid-­‐brain limbic systems (emotions, blue-­‐ribbon, grade A emotions) à cortical areas (higher cognitive functions, higher sentiments) à table 4.3, p.99 Seven primary affective systems (basic, shaped by evolution): seeking, rage, fear, lust, care, panic, play can all be influenced by serotonin (5-­‐HT) and norepinephrine (NE) (general effects) some systems are also effected by specific neurotransmitters depending on where they are in the brain à Table 4.4., p.99 !!!!! -­‐
Oxytocin, maternal care and romantic love -­‐ à Care system -­‐ Oxytocin is crucial for the development of maternal behavior, pair-­‐bonding and maybe even romantic love -­‐ + important for female sexuality, childbirth, breastfeeding -­‐ + wider role in the development of nurturance and maternal behavior -­‐ Rats that engage in more licking and grooming: more oxytocin receptors in the bed nucleus of the stria terminalis (BNST) -­‐ Those rats that received higher levels of licking and grooming as pups had more oxytocin receptors in the BNST, central nucleus, amygdala -­‐ à were far less fearless and more maternal (blocking oxytocin stops maternal behavior!) -­‐ Oxytocin is also involved in the panic system -­‐ à related to separation and distress -­‐ Injection of oxytocin reduces the number of distress calls when separated from mother -­‐ Reduction of oxytocin leads to increased separation distress and less nurturing -­‐ = Double dissociation between two systems (panic and care) + underlying chemistry à difficult to separate neural circuits -­‐ each neurochemical is involved in several emotions (due to natural selection each became gradually involved in more than one emotion) -­‐ Oxytocin: originally female sexuality & milk production -­‐ Now also maternal behavior and maybe even feelings of romantic & maternal love? à it is critical for pair bonding but not clear if this is mediated by feelings -­‐ Greater activation of oxytocin receptors inn insula, cortex & subcortical areas activated when shown photograph of loved one (but no indication of oxytocin levels)-­‐> no proof of feelings -­‐ Other experiments showed that oxytocin correlated with behavioral indicators of love but NOT with feelings Le Doux’s approach: fear conditioning -­‐ Experiments with rats: amygdala is crucial in processing fear -­‐
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Position of amygdala etc. p.102, figure 4.6. Amygdala has up to 13 different sections 3 major parts: corticomedial nuclei, basolateral nuclei, central nucleus 2 different routes from auditory fear stimulus to amygdala: soundà detection by specialized cells in the earà thalamus à 1. Directly to the amygdala (low road, fast) à 2. Auditory cortex à amygdala (high road, slow) see figure 4.7, p.103 amygdala is important for learning of danger signals (conditioned fear response-­‐ CFR)à survival mechanism No CFR if basolateral nuclei is removed or inactivated! Context (learning environment) is important à fear reactions to particular room in which conditioning took place even in absence of CS = contextual fear association à depends on hippocampus!! à episodic memory! Without hippocampus CFR can be learned but no context association Maintenance of fear: CFR is fairly persistent unless the CS is presented many times in the absence of the US = extinction à depends on areas in the PFC If medial PFC is damaged in rats: extinction is impaired à medial PFC is important for regulating how the amygdala and hippocampus respond to situations/stimuli based on their affective significance Effects of amygdala damage in non-­‐human primates -­‐ Kluver-­‐Bucy Syndrome: -­‐ when temporal lobes of monkeys were removedà animals became tame, non-­‐
aggressive, lost fear of stimuli of which they were normally afraid, hypersexual, tendency to eat non-­‐food items -­‐ Entire temporal lobes were removed not only the amygdala -­‐ but amygdala does seem to be the key structure determining the affective significance of a stimuli -­‐ Ablation of amygdala: reduced fear of snakes (reduction in facial expression and vocalizations) -­‐ Damage to PFC: deficits in emotional display, disruption of a number of social behaviors -­‐ High concentrations of serotonin receptors in amygdala and vmPFC of monkeys that show competent social behaviors -­‐ à importance of connection between subcortical & cortical regions & emotional responses -­‐ Structures extending from the temporal lobe and amygdala through the anterior and medial hypothalamus, through the periaqueductal grey area (PAG) and then down to the brain stem, lower brain stem, spinal cord: control many physiological symptoms of fear -­‐ à areas are richly connected to other regions, incl. cortex Human research Lesion studies -­‐
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Phineas Gageà damage to both frontal corticesà especially the vmPFC on the left side! Language and memory intact Personality change: impatient, socially inappropriate, unreliable, little deference for other people PFC is important for several aspects of emotional functioning Studies on subcortical damage: Consequence of amygdala damage in humans: not as dramatic as in monkeys!! But very specific deficit in recognition of fear displays (facial expression and vocalization), recognition of other emotions left intact Patients DR (removal of both amygdalae) and SE (damage to both amygdalae): severe difficulties recognizing fear expressions, to a lesser degree anger expressions However: some patients have a range of deficits while some have no problems at all with recognizing expression à role of amygdala is complex! Damage to insula and basal ganglia regions: difficulty recognizing facial expressions & vocalizations + abnormalities in experience of disgust Electric stimulations of the insula: unpleasant sensation of the stomach, nausea, unpleasant tastes Huntington’s disease: effects basal ganglia (striatum) à problems recognizing disgust à different neural circuits underlying fear and disgust (but likely to be some overlap) Recent research: ventral basal ganglia (striatum) lesions: deficits in recognizing anger Feelings or recognition? Amygdala, PAG, hypothalamus, brain stem: people report strong feelings of emotions when simulated in these areas Fear conditioning with brain injured patients -­‐ Amygdala: conditioned fear response (implicit association between CS and US) -­‐ Hippocampus: explicit learning of fear (no normal fear response to CS) -­‐ Bilateral damage to both amygdala and hippocampus: neither explicit association nor fear response -­‐ Amygdala is important when you have to respond instantly in a new situation (immediate response even if you don’t explicitly know what the threat is or if a threat appears in a new context) -­‐ Experiment: telling patients that they might receive a shock when seeing a blue square: developed normal fear response even though no shock was ever administered (normal patients) -­‐ Amygdala patients: could report explicit link but did not develop fear response -­‐ à explicit knowledge: hippocampus sends signal to amygdalaà fear response Is the amygdala specific to fear? -­‐ Also involved in several other emotions -­‐ Punishment and reward -­‐ Positive stimuli (e.g. happy faces) -­‐ à response is strongly modulated by personality traits -­‐ not clear if amygdala is part of a neural circuit specific to fear or one that is underlying any significant affective stimuli Brain imaging of emotions -­‐
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problem with these studies: no clear distinction between emotion, mood, feelings also between expression and perception of emotion many of these different aspect of emotions have different neural substrates most studies use photographs of facial expressions found clear differential activation of the left amygdala to fearful compared to happy faces study found that amygdala is activated by high intensity fearful expressions + hippocampus, anterior insula, putamen: activated to increasing intensities by fearful, disgusted and happy expression + linear decreases in hippocampus and putamen responses to increasing intensities of sadness Other study: no differential activation, but a number of brain regions tend to respond to increasing intensities of emotions Meta analysis: most consistently activated brain region for each emotion: 1. Fear-­‐ amygdala 2. Disgust – insula/operculum and globus pallidus 3. anger – lateral orbitofrontal cortex (OFC) 4. Happiness – rostral supracallosal ACC/dorsomedial prefrontal cortex (dmPFC) 5. Sadness – rostral supracallosal ACC/ dmPFC fear, disgust, anger can be distinguished all others no difference in neural activation between sadness and happiness regions of the anterior cingulate and mPFC (rsACC, dmPFC) were activated during most discrete emotions à more general role some brain areas may play a role in both perception and experience of emotions others play a more specific role Distinctive antecedent events -­‐ another criterion for basic emotions: emotions should be elicited by a distinctive antecedent event -­‐ 2 different types of stimuli that elicit specific emotions: 1. biologically primed stimuli, 2. learned stimuli -­‐ e.g. rats can get trained fear response through CC, they show a natural fear response to the smell of cats (even if they never met one) -­‐ most situation: emotional response result of both evolution and social learning -­‐ Selective learning process: monkeys learn to fear a toy snake but not flowers when watching other monkeys fear responses Appraisal models of emotions -­‐ many psychologists argue: -­‐ it is the appraisal of the situation which gives it a particular meaning -­‐ this in turn elicits the emotion -­‐ à basic emotions can be reduced to basic appraisal scenarios -­‐ small set of high-­‐level goals associated with a core set of appraisal and action processes -­‐ core goals are shared across culturesà appraisal linked to these goals are fundamental cognitive processes that result in basic emotions -­‐
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Magda Arnold: people evaluate situations of 3 key dimensions: 1. Is the situation beneficial or harmful? 2. Is an important object present or absent, 3. is the object difficult to approach or avoid? People constantly evaluate the environment for changes that might be relevant for our well-­‐being Appraisals result in specific action tendencies (experienced as emotions) Each appraisal type unfolds sequentially over time, receives input form a variety of cognitive and motivational processes (e.g. attention, memory, reasoning, concept of self) Appraisal theories differ from categorical theories of emotion: they do not assume that distinct basic emotions are produced by innate hard-­‐wired neural circuitsà there are as many different emotions as there are reliably differentiated appraisals But: many argue that there are is a smaller number of emotions that help an organism to adapt Klaus Scherer: these are modal emotions rather than basic emotions modal emotions = emotions most commonly experienced across cultures 2 appraisal theories: 1. Richard Lazarus -­‐ cognitive-­‐motivational-­‐relational theory -­‐ each discrete emotion is associated with a ‘core relational theme’ -­‐ each core relational theme (common situations) elicits a specific emotion (for an overview: p.115, table 4.6) -­‐ Problems with this theory: -­‐ rather circular: as we might for instance define anger as the emotion that occurs when we appraise a situation as demeaning to us (which is the core relational theme) -­‐ Also you could also be experience anger or aggression in a dangerous situation (not only fear) 2. Oatley and Johnson-­‐Laird -­‐ acknowledge the functional nature of emotions while accepting that cognitive appraisal is critical for their differentiation and evaluation -­‐ primary function of discrete emotions is to provide a means by which important life goals can be pursued -­‐ an event is appraised in relation to various goals -­‐ appraisals occur automatically (unconsciously), driven by a small set of basic emotions -­‐ 2 major problem areas: 1. Personal goals, 2. Unpredictability of surroundings -­‐ goals: not being killed, finding food, finding a mate, finding shelter … -­‐ at any moment everyone has several goals competing for priority -­‐ cognitive systems must be highly flexible in order to cope with unpredictable events -­‐ emotions play a key role in prioritizing and organizing goals in a flexible way -­‐ emotions set the entire cognitive system into a specific mode -­‐ Environmental event à emotion signal forces change to another mode -­‐
When a key juncture occurs between plans or goals: cognitive appraisalà emotions allow the system to switch rapidly (overview of junctures and basic emotions p.117, table 4.7)