Emotion-Oriented Systems

Catherine Pelachaud

• Publisher: Wiley-ISTE
• Year: 2013
• ISBN:
  9781118603321
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Electrical Engineering & Telecommunications
• Index: Technology & Engineering

The Affective Computing domain, term coined by Rosalind Picard in 1997, gathers several scientific areas such as computer science, cognitive science, psychology, design and art. The humane-machine interaction systems are no longer solely fast and efficient. They aim to offer to users affective experiences: user's affective state is detected and considered within the interaction; the system displays affective state; it can reason about their implication to achieve a task or resolve a problem. In this book, we have chosen to cover various domains of research in emotion-oriented systems. Our aim is also to highlight the importance to base the computational model on theoretical foundations and on natural data.

PART 1

Foundations

Chapter 1

Contemporary Theories and Concepts in the Psychology of Emotions ¹

Is emotion more than a chapter heading?

Bentley, 1928

Everyone knows what an emotion is, until asked to give a definition. Then, it seems, no one knows.

Fehr and Russell, 1984

1.1. Introduction

Following the decisive change of the 1980s, which was marked by a veritable explosion in the scientific study of emotions, emotion is now considered to be a determining explanatory factor in human behavior. In this context, it seems important for any area of research into the functioning of psychological processes and their modeling, as is the case in informatics, to consider current theories and concepts in the psychology of emotions [SAN 09a, SAN 09b]. The central role of emotion in the cognitive system is illustrated by the fact that emotion occupies a “privileged status” in the human brain [DAV 04]; the majority of psychological mechanisms are either necessary for emotion, as such, or are influenced by emotion or involved in regulating emotions. However, as the above quotations suggest, conceptual precision of emotion remains a problem [ALV 02], so much so that there are almost as many definitions of emotion as there are theories and/or researchers working on this topic [KLE 81, STR 96]. In this introductory chapter, we will present the main contemporary theories and concepts of emotion, touching on the notions established towards the end of the 19th Century in which modern approaches are rooted. For each major current theory, we will present its premise, its main assumptions and its characteristics as well as the criticisms that have been aimed at it. As we will see, there is huge variation in the contribution to these theories towards discovering the functional architecture of emotional mechanisms which consists of characterizing the functional sub-systems responsible for the different stages of processing needed to produce emotions and specifying the organization and interaction of these sub-systems [FEL 05, KOR 11, SAN 02].

1.2. Emergence of a scientific approach to emotions

1.2.1. The emotional sequence: James-Lange versus Cannon-Bard

The first “scientific” emotional theory was proposed by William James in 1884 [JAM 84] and Carl Lange in 1885 [LAN 85], who each separately proposed a revolutionary “peripheralist” approach to emotion. This first theoretical conception was the focus of great controversy concerning the mechanisms responsible for triggering emotional feeling (the “sequence problem” [CAN 77]). According to James and Lange, what had previously been considered as the consequence of an emotion, they now considered to be the cause. According to them, the elicitation of a particular emotion is determined by the perception of a specific peripheral arousal pattern, i.e. we experience fear because we are trembling. It should be underlined that, according to James, this definition of emotion is only applicable to emotions that accompany a “specific physical reaction” and not all emotions, resulting in misinterpretations of this theory in later years. In 1885, Lange [LAN 85], summarized the problem of their theory in the following way:

“If I begin to tremble because I am threatened by a loaded pistol, does first a physical process occur within me, does terror arise, is that what causes my trembling, palpitation of the heart, and confusion of thought; or are these bodily phenomena produced directly by the terrifying cause, so that the emotion consists exclusively of the functional disturbances in my body?”

Clearly, the second position is the one supported by James and Lange. However, whilst their proposition was in complete conflict with the general consensus and traditional concepts of emotion, these authors recaptured the time-honored idea that each emotion has its own pattern of physiological changes [RIM 86]. It should be noted at this point that James’ opinions were much more nuanced than this with regard to emotion appraisal theories, as we will see later in this chapter [ELL 94].

In contrast to this, the so-called “centralist” approach to emotion, supported by Cannon [CAN 27] and Bard [BAR 28], sees the triggering of a specific emotion as being determined by processing a stimulus in the “central” nervous system, with the peripheral arousal pattern being neither specific nor causal. This theory therefore highlights the importance of the central nervous system, specifically the thalamus, in triggering a given emotion. As such, the physiological changes are not considered to be a cause, but rather a consequence of emotion. Cannon raised numerous objections to the James-Lange theory and carried out a number of empirical studies that aimed to disprove it; for example, he observed that similar diffuse visceral reactions occur with a number of emotions as well as in non-emotional states (i.e. digestion or fever); he also reported that suppressing visceral afferents did not suppress emotions [CAN 27]. However, as Fraisse [FRA 63] has notably found, the criticisms raised by Cannon were not without fault and therefore did not warrant an outright rejection of the James-Lange theory [FEH 70].

The theories of James-Lange and Cannon-Bard, both based on a physiological approach but radically opposed with regard to their conception of the temporal sequence of emotion, have had a considerable impact on research of emotion, on the one hand initiating research into the causal relationship between physiological changes and emotion, and on the other hand, studies into the importance of “cognition” in emotion.

The James-Lange theory has had a revolutionary effect due to the originality of the concepts that it proposed, as well as due to the fact that it was empirically testable and therefore refutable. Their theory has also strongly influenced current researchers of emotion. Today, Damasio’s theory of somatic markers [DAM 94] revives the James-Lange idea of the causal role of physical changes in emotion by hypothesizing that there are “somatic markers” i.e. physiological reactions, associated with past emotional events. These markers are supposed to be activated when a new event is processed and would influence decisions in relation to their potential consequences. On the other hand, James’ theory could be considered to be the basis of facial feedback theories of emotion, which assumes that facial movements regulate emotional feeling. According to James [JAM 92], “every voluntary and dispassionate display of what we believe between the manifestation of a specific emotion should produce this emotion in us”. Embodiment Theories of Emotion [NIE 07] have also been influenced by the James-Lange theory since they propose that cerebral representations of a given emotion involve retesting perceptive, motor and somato-sensory components in relation with this emotion.

The importance of the James-Lange/Cannon-Bard debate surrounding awareness of the role of cognition in emotion is illustrated by the work undertaken by Schachter, who is among one of the most influential pioneering contributors in the field of affective sciences.

1.2.2. Schachter’s two-factor theory

According to Schachter’s bifactorial theory [SCH 64], an emotion is determined by an interaction between two components: a physiological arousal and a cognition regarding the recognition of the situation triggering this physiological arousal. As such, physical arousal is considered to be undifferentiated by nature, diffuse and non-specific to an emotion in determining the intensity but not the quality of the emotion. The interpretation of the situation would lead to the identification of the emotion felt.

Schachter and Singer [SCH 62] wrote that “it is cognition which determines whether the physiological state of arousal will be labeled as ‘anger’, ‘joy’, ‘fear’ or ‘other’”. Schachter and Singer therefore share James-Lange’s idea that a physiological arousal is necessary in order for an emotion to be produced while also agreeing with Cannon-Bard that physiological changes are not specific to a particular emotion. (Whilst they do not exclude the possibility of physiological changes differing according to the emotion, they believe that these differences would be too subtle to have a psychological effect.) Note that the temporal coincidence between the two components is not a sufficient condition for triggering an emotion: the person needs to establish a link between the physiological arousal and a relevant explanation for the latter.

Schachter and Singer’s famous experiment [SCH 62] is typically cited as fundamental experimental proof of this theory. This has essentially suggested that when a person does not have information that is likely to explain why they are physically stimulated, they will rely on information available in the situation and context in order to make sense of their physiological arousal (which in this experiment was triggered by an injection of epinephrine). However, when the person is not in a particular state of physiological arousal (without an injection of epinephrine), or where he/she has an adequate explanation for it (information on the consequences of the injection of epinephrine), they will not look for factors in the environment that explain this arousal. However, the effects predicted by Schachter and Singer’s proposition are not systematically observed (see [REI 83] for a review of experiments in the same vein as Schachter and Singer). On the other hand, the component determining which stimuli trigger the physiological arousal in the first place is not specified; this theory therefore does not explain the emotion-triggering process.

Schachter, by introducing the existence of a cognitive components associated with physiological arousal as a determinant of emotional quality, is clearly one of the forerunners of a cognitive approach to emotions. Furthermore, his theory has the advantage of considering the social dimension of emotion, since emotion stems in part from the use of information taken from the social environment. Another theoretical trend, falling within the evolutionary perspective, has also highlighted the social dimension of emotion by focusing specifically on the communicative function of emotions through their expressions.

1.3. Basic emotions theories

1.3.1. Premises of basic emotions theories

Some theoreticians with an evolutionary perspective, who believe that evolution has played a central role in shaping the emotions’ characteristics and functions, have stressed the notion of emotions adaptation. These characteristics and functions appeal to programs that govern the body’s major systems, such as physiology, the motor system, as well as numerous cognitive mechanisms such as attention, learning or even memory; emotion is therefore a high level-organizing process [COS 00]. Matsumoto an...