Emotions play a central role in the life of every human being. They shape our actions, our thoughts, and our relationships. They help us to detect, identify, and understand what is important to form memories and to make decisions. They guide our everyday actions. Because they are so central to our lives, emotions have been studied by researchers in disciplines across the cognitive and affective sciences (psychology, linguistics, philosophy, sociology, anthropology, computer science, psychiatry, and neuropsychology).
The psychology of emotions is a vast research area, which has made a great deal of progress over the past 30 years (see Barrett, 2018; Barrett et al., 2016; Luminet et al., 2013; Niedenthal & Ric, 2017; Sander & Scherer, 2019, for general overviews). At both the theoretical and empirical levels, research in this area is increasingly abundant and technically sophisticated. Psychologists have explored many questions about emotions (see Table 1.1 for some examples). As researchers have sought to answer these questions, they have made significant progress on determining what emotions are (their components), when and under what conditions we experience them (their causes and determinants), why we have them (their functions), how universal they are (cultural, inter- and intra-individual, and developmental differences), and their impact on psychological functions such as cognition. This book focuses on the last of these questions. It surveys research on how emotions and cognition are linked. This opening chapter presents the questions about emotion-cognition relations that researchers have tried to answer thus far, and the methods they have used to do so. It begins with a general definition of emotions. It then presents the major research questions on emotion-cognition relations, and what makes these questions interesting and important. Finally, it presents the cognitive functions covered in this book. These are functions that psychologists have already accumulated enough data about to allow us to understand how emotions affect them.
1.1 What is an emotion?
Many definitions of emotions have been proposed. While they differ on some points, these definitions have in common that they take emotions to be internal states that may be (but need not always be) observable through expressions (facial, verbal, and more) and behavior. In most cases, emotions are accompanied by physiological reactions (e.g., changes in heart rate, electrodermal responses, skin conductivity, muscular activity). To take one example, Keltner and Gross (1999) defined emotions as âepisodic, relatively short-term, biologically based patterns of perception, experience, physiology, action, and communication that occur in response to specific physical and social challenges and opportunitiesâ (p. 468). An emotion is thus a set of (psychological and/or physiological) responses of variable intensity, duration, and complexity. These responses can be more or less public or private, and more or less synchronized. Note, finally, that an emotion occurs when we find ourselves in a situation that we evaluate in some way (as dangerous or safe, pleasant or disagreeable).
There are several types of emotions, and scientists are still discussing what the best taxonomy of emotions is (e.g., Keltner, 2019; Keltner et al., 2019). While many psychologists believe that it is important to distinguish between the so-called basic emotions (joy, anger, sadness, disgust, fear) and self-conscious emotions (jealousy, envy, shame, guilt, embarrassment, pride), two dimensions characterize all emotions: valence (positive or negative emotion) and arousal (weak or strong emotion). These dimensions vary continuously, so that a situation or stimulus can have a more or less positive or negative emotional valence, and involve more or less emotional arousal (e.g., Plutchik, 1991; Russell, 1980; Watson & Tellegen, 1985).
Each emotion has its own general profile of psychological, behavioral, and physiological expressions, although this profile may vary between individuals and, in the same individual, between situations. Joy, for example, often results from the achievement of an important goal or the satisfaction of a need. It is expressed by smiling, an increase in the fundamental frequency, dynamic range, and intensity of the voice, as well as increased heart rate and body temperature. Anger is often triggered by an unexpected event intentionally caused by another person, which we perceive as an obstacle to achieving an important goal and/or meeting a need. It is expressed by a hard, tense face, and is accompanied by an increase in the voiceâs fundamental frequency, intensity, and energy at high frequencies, as well as an accelerated heart rate, increased muscle tension, and changes in breathing. Sadness is often the result of an event or situation that prevents us from satisfying a need for a prolonged period, and that is perceived as difficult or even impossible to control. It is accompanied by a feeling of helplessness, drooping eyelids, a lowering of the voice, the rate of speech, and muscle tension, as well as the urge to cry. As a final example, fear is caused by a sudden event that we perceive as threatening our survival or our physical or mental integrity. It is accompanied by a terrorized facial expression and increases in the fundamental frequency and pitch of the voice, as well as the rate of speech. The heart rate also quickens, breathing and body temperature change, and the throat tightens. The diversity of the psychological, behavioral and physiological responses associated with each emotion is interesting for psychologists who are trying to understand the links between emotion and cognition. For example, to check that a participant is in fact in a certain emotional state while performing a cognitive task, experimenters can collect a set of measurements that, taken together, provide a reliable and valid indicator of that emotional state.
Emotions differ from both moods (which do not necessarily have a specific object and can be more diffuse and longer-lasting) and sentiments or feelings. Emotions differ from sentiments in terms of a number of characteristics, such as their intensity, duration, objects, expression, and manifestations (public or private). Not all researchers agree on the criteria, but they generally concur that emotions and sentiments are different, although the two may be related (e.g., certain sentiments or feelings may be based on certain emotions; Damasio, 2010).
Finally, to understand emotions, researchers try to determine not only what they are, when they occur, how they are triggered, and their effects on other psychological dimensions but also their functions (see Scherer & Ekman, 1984, for a discussion). For example, emotions may orient our tastes, make life richer and more interesting, help us to avoid or escape from danger, facilitate (or hinder) communication between individuals and groups, support the pursuit of a goal, prepare us for action, and serve or help us to evaluate various elements of our worldâpeople, animals, objects, situationsâin order to adjust our behavior (e.g., to flee in case of danger) and ensure our survival and safety. It is no wonder, then, that they influence our cognitive functions.