EMOTIONS. Phil/Psych 256. Chris Eliasmith

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1 EMOTIONS Phil/Psych 256 Chris Eliasmith

2 Role of Emotions An essential part of what makes us human, but often making us poor reasoners? An essential part of what makes us human, and responsible for making us as good reasoners as we are? Just a pain in the butt (make us bad reasoners, are evolutionary leftovers that are one of the least human parts of us, etc.)?

3 What would life without emotions be like?

4 Emotions and Decisions Traditional models of decision making are based on economic theory in which participants are assumed to be rational decision makers. The emotion challenge to CRUM is largely a product of the work of of Antonio Damasio and his collaborators. Their patients (e.g. EVR) have ventromedial prefrontal cortex damage Patients have serious emotional impairments, that make them poor decision makers Yet, they have fairly intact/normal verbal and mathematical abilities. They seem to have lost (controlled?) emotions, but surprisingly this affects traditionally cognitive abilities. In retrospect, the famous historical case of Phineas Gage, seems to be explicable given these recent patients with similar damage.

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6 Iowa Gambling Task A B Preferred by normals Preferred by VM patients Low immediate return, long term payoff High immediate return, long term loss Maximize the payoff you get from betting on the decks.

7 Iowa Gambling Task Normals eventually bet only on A. GSR indicates the better deck before they know that it is the better deck. Those with VMPFC damage continue to bet on deck B (as much as A, or more) they have little GSR Therefore, those with VM damage are poor decision makers. Therefore, ignoring the role of emotions will be disastrous to good explanations of cognition.

8 Two Possible Changes to CRUM Expansion: No change in basic ideas, extend them to apply to new phenomena Introduce new content to representations (e.g. about bodily states). Also identify new processes that take advantage of the repns Problems: Thagard says this will not be a satisfactory solution because treating an emotion as just another concept conceals its links with judgment, physiology, and feeling (p. 166). That is, emotions are closely tied to what it is like to be in the world in a way that representations can't reflect. Unlike simulating problem solving, simulating emotions doesn't result in the relevant property (finding a solution vs feeling sweaty, perhaps).

9 Expanding CRUM (cont.) Response: Why is experiencing an emotional representation qualitatively different than experiencing a perceptual representation? I.e., what's so special about emotions that make them unrepresentable? (or lacking when repersented?) Emotion repns may participate in different kinds of processes (that result in bodily changes). Because robot bodies are so different I doubt that computers will ever have emotions at all like humans (p. 170). Seems to change the target of expln. What does at all like mean?

10 Two Possible Changes to CRUM Supplementation: Necessitates rethinking the fundamental commitments of CRUM Thagard argues that emotional representations need to be felt, and to have bodily inputs. Maybe we need to identify different kinds of processes in order to explain emotions? Suggests that new kinds of representations might have to be discovered (ones that are somehow 'more biological ; sensitive to global, hormonal influences and complex biophysical feedback)

11 Supplementing CRUM (cont.) Problems: Similar to the expansion response Pointing out that the brain uses distributed representations is no more damaging to a characterization of emotions than to a characterization of anything else. Why is the brain more important for understanding emotions than for anything else? Emotions arise from the particular kinds of computation performed by the brain (p. 166) Thus CRUM doesn't need to be supplemented (if it didn t already need to be )

12 Cognitivism Paul Griffiths presents a theory of emotions, along with a critique of the cognitivist position. Cognitivism (Thagard attributes this kind of view to Oatley): 1. All emotions have corresponding propositional attitudes. 2. The kind of emotion elicited depends on the kinds of attitudes (e.g. desiring, believing, etc.) involved The 'big problem' for this theory is that it can't explain how emotion and beliefs can contradict one another Phobias (believe there is nothing to fear from a snake, but still fear it) Imagined stimuli (no reason that imagining a stimulus should cause an affect, but it often does)

13 Psychoevolutionary Theory There is a set of 'affect-programs' that are automatic, modular, involuntary, and innate. They are triggered by stimuli and result in physiological changes and mental states (reflex-like, but more complex and structured) They operate in parallel with, but independently from 'normal belief fixation' (i.e., process of seeing a stimuli and coming to have some attitudes towards the propositions it gives rise to). Doesn t cover all emotions, just the basic/common ones

14 Two Theories of Emotion Cognitivism Modularity (Griffiths)

15 Modularity Griffiths claim that emotions are modular carries two central commitments: First, modules are informationally encapsulated This means they don't have access to information outside of their local processing (the information processing is strictly feedforward) Second, modules are often thought to be innate They have developed over evolutionary time to do a specific task (quickly and efficiently) They are 'prespecified' by the genes under normal developmental conditions.

16 Evidence for Informational Encapsulation Evidence for: 1. Involuntariness of emotional responses (e.g. Ekman and Freisen 1980 study in Japan). 2. Must explain how emotional responses can conflict with other cognitive activity. They can easily conflict if they are the result of an entirely separate processing stream. 3. Old parts of the brain seem to be responsible for much emotional processing (e.g. limbic system, incl. amygdala, hypothalamus).

17 Evidence Against Informational Encapsulation Evidence against: 1. Schacter and Singer (1962) showed that inducing physiological changes (by adrenalin injections) can be interpreted in very different ways depending on other stimuli (top-down affects on emotion) NB: These results haven't been well reproduced and may be subject to confabulation). 2. Involuntariness doesn't imply modularity. See e.g. the visual system (recall non-hierarchical processing). 3. Does conflict imply modularity? People often have conflicting beliefs (e.g. that something looks 3D but is only 2D in the case of various optical illusions). 4. Neuroanatomy: massive interconnections between most areas (in particular between amygdala and cortex).

18 Universality of Emotions

19 Evidence for Innateness 1. Eckman and Friesen (1971) showed that even 'isolated' humans could easily distinguish facial expressions typical of certain emotional states. 2. Levenson, et al. (1992) showed ANS responses were similar for Americans and the culturally very different Sumatran Minangkabau 3. Eibl-Eibesfeldt (1973) found that blind and deaf children automatically use the same facial muscles to display the same kinds of emotions as non-blind and deaf children 4. Display rules explain cultural differences (Ekman and Freisen 1980). The initial characteristic responses were similar across cultures. 5. Preparedness for learning associations with evolutionarily relevant stimuli, and difficulty in extinguishing these associations (e.g. young monkeys viewing fear in an adult).

20 Universality of Emotions

21 Cross-cultural similarity of ANS Responses

22 Discussion Thagard and Griffiths agree that the RTM version of CRUM fails. Both offer good reasons to expand CRUM in important ways (i.e., by taking into account new kinds of representational content and looking to see what novel processes might operate given that content) They also argue for stronger positions: Thagard thinks CRUM needs to be supplemented But, he doesn't specify what new kinds of representations will be needed, and why they would be different in kind from, say a distributed representation, which already is part of CRUM. Griffiths suggests certain kinds of processing (informationally encapsulated processing) will be necessary to account for emotions He also thinks this processing is very different from what goes on in 'normal belief fixation'. Given what we have learned about other modularity claims, it would be more prudent to suggest we just don't know enough about the system to know precisely how it is integrated into belief fixation (to think that it is truly independent of more cortical processing, seems naïve)