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In the past few decades, research in the psychology of emotion has benefited greatly from being located in a firm evolutionary framework. It is argued that research in the psychology of mood might attain equal rigour by taking a similar approach. An evolutionary framework for mood research would be based on evolutionary psychology, the main thesis of which is the Massive Modularity Hypothesis. Translating the folk-psychological language of moods into the scientific language of modules might clarify many theoretical questions and provide a sound basis for empirical research. It is argued that such an evolutionary approach would reveal mood to be a much more heterogeneous category than emotion. While the six basic emotions identified by Paul Ekman are probably each subserved by a single module, prototypical moods such as elation, depression, anxiety and irritability are likely to be subserved by a wide range of modules. An evolutionary approach to mood might therefore lead to the elimination of the concept of mood from scientific psychology altogether. Introduction Evolutionary psychology is a relatively new research program that aims to map the human mind by combining cognitive psychology with evolutionary biology (Tooby and Cosmides, 1992). It is thoroughly cognitive in regarding the mind as an information-processing device that can be described in computational terms. Unlike most cognitive psychologists, however, who regard the mind as a general-purpose problem-solver, evolutionary psychologists argue that the mind consists of a large number of special-purpose devices, which are usually referred to as 'modules'. This view has since become known as the 'Massive Modularity Hypothesis' (Murphy and Stich, 1998; Samuels, 1998), after a phrase originally coined by Dan Sperber (Sperber, 1994). Since Fodor introduced the term in 1983, the term 'module' is used - some might say misused or even abused - in an increasing number of works in cognitive psychology (Fodor, 1983). However, different theorists use the term in different ways, and rarely take the trouble to define it in any detail (Segal, 1996). Evolutionary psychologists have not been exempt from this lack of precision (Samuels, 1998). Nevertheless, it is possible to infer a coherent concept of modularity from the writings of various evolutionary psychologists. Following Samuels (1998), I will use the term 'Darwinian module' to refer to this concept. A Darwinian module is a computational mechanism that is domain-specific, informationally-encapsulated; it is designed by natural selection as part of the universal species-typical design, and is thus innately specified/genetically determined. Darwinian modules have a typical ontogenetic pace and sequencing, and are often associated with characteristic breakdown patterns. They may also be associated with a specific neural or biochemical architecture, in which case they cannot be implemented by just any neural mechanism. Those cognitive psychologists who argue that the mind has some degree of modularity usually restrict this to input and output systems. That is, they claim that input systems such as vision, and output systems (those responsible for direct muscular control), are likely to be modular, but that central systems (those responsible for 'higher' cognitive processes like reasoning) are nonmodular (Fodor, 1983). Evolutionary psychologists, on the other hand, argue that the whole mind, including the central processes, are likely to be modular (Sperber, 1994). If this is true, it has important consequences not just for our understanding of reasoning and other classically 'cognitive' processes, but also for our understanding of emotion and mood. The modularity of emotion Evolutionary theories of emotion have their roots in Darwin's own work. His 1872 book, The Expression of the Emotions in Man and Animals, traced many human facial expressions and bodily gestures to their putative origins in pre-human ancestors. For example, Darwin argued that the way that humans bare their teeth when scowling with anger was a vestige of a primitive agonistic display that can still be observed in modern chimpanzees (Darwin, 1872: 12). Despite the initial popularity of Darwin's book among the general public, it is only recently that it has had a similarly powerful impact on the work of professional psychologists. The neglect of Darwin's theory by psychologists throughout much of the twentieth century was closely connected with the culturalist theory that dominated psychological research in emotion during this time. According to this theory, the expression of emotion, and even the emotions themselves, were culturally specific, learned phenomena (La Barre, 1947). In the early 1970s, however, studies by Paul Ekman and colleagues began to provide strong evidence against the culturalist view. Studies of a remote preliterate culture in New Guinea strongly suggested that certain facial expressions were universally associated with a small range of 'basic emotions': surprise, joy, sadness, fear, anger and disgust (Ekman and Friesen, 1971). Ekman went on to argue that each of these basic emotions was characterised by a distinctive pattern of facial expressions and physiological changes, and was triggered by distinct kinds of event (Ekman, 1992). All the basic emotions tended to have a rapid and unbidden onset, and to last for seconds rather than minutes, hours or days. Ekman argued that the co-occurrence of this cluster of properties could only be explained by supposing that basic emotions are adaptations that evolved because they helped our ancestors to deal with 'fundamental life-tasks'(Ekman, 1992: 171). As Paul Griffiths has argued, the properties that Ekman associates with the six basic emotions are among those that characterise Darwinian modules (Griffiths, 1990). Like modules, the operation of basic emotions is mandatory, fast, and informationally encapsulated. Like modules, the representations that govern basic emotions are often inaccessible to other mental processes. There is also increasing evidence that some basic emotions such as fear are 'hardwired'; that is, they are implemented by a specific neural architecture (LeDoux, 1998). Furthermore, the co-occurrence of these properties supports the contention that basic emotions are adaptations in exactly the same way that it supports the view that modules are adaptations. It is therefore plausible to identify basic emotions with a subset of Darwinian modules. To be more precise, it is not the basic emotions themselves that should be identified with modules, but rather what Ekman calls the 'automatic appraisal mechanism' of the basic emotions. Ekman defines a basic emotion as a distinctive pattern of facial signals and physiological responses that is regularly associated with a distinctive kind of antecedent event. This analysis can appear rather behaviouristic, in that it links certain stimuli with certain responses without specifying the psychological mechanism that mediates the response. However, Ekman does not neglect the psychological dimension entirely, as is clear from his discussion of the mechanisms that detect and appraise emotionally relevant stimuli and coordinate the various facial and physiological changes that constitute the appropriate response to these stimuli. He terms these mechanisms 'automatic appraisal mechanisms' (AAM), and develops a basic model of how they work (Ekman, 1992: 185-87). Each emotion would be subserved by a distinct AAM, which would only attend to a particular range of stimuli. It is the AAM of a given emotion, rather than the emotion itself, that should be conceived of as a Darwinian module. The claim that the AAMs associated with basic emotions are Darwinian modules involves more than the idea that basic emotions are subserved by psychological mechanisms that are domain specific, informationally encapsulated, hardwired, and so on. It also involves the claim that these mechanisms are adaptations. This is also consistent with Ekman's view of basic emotions. Similar arguments have also been advanced by a number of other theorists, including Robert Plutchik, R. S. Lazarus, Randolph Nesse, and John Tooby and Leda Cosmides (Plutchik, 1980; Nesse, 1990; Tooby and Cosmides, 1990; Lazarus, 1991). A crucial part of all these accounts consists of formulating hypotheses about the function of each of the various basic emotions. Such hypotheses posit that a given emotion evolved because it helped our ancestors to solve a particular problem. For example, all the theorists argue that fear evolved because it helped our ancestors to solve the problem of evading predators. Those of our ancestors who had the capacity for fear survived longer than, and thus out-reproduced, those who did not. This kind of hypothesis is often referred to as an 'adaptationist hypothesis' because it claims that natural selection was the major force in the evolution of a given trait rather than, say, genetic drift. Translated into the terminology of evolutionary psychology, then, the work by Ekman and other evolutionary theorists of emotion suggests that there is a class of Darwinian modules whose function is to produce the characteristic patterns of facial expression and physiological change that we refer to as surprise, joy, sadness, fear, anger and disgust in response to certain situations. But what about other kinds of affective phenomena? Can the evolutionary model be extended to cover other emotions such as guilt, shame, and love? If so, might it extended even further, to cover moods such as anxiety, elation and depression? The question of whether there are modules whose function is to produce what Griffiths has termed 'higher cognitive emotions' such as guilt, shame, and love has been explored elsewhere, and will not be addressed here (Griffiths, 1997: 120-22). What interests me is the question of whether there are modules whose function is to produce the kinds of thing that are commonly referred to as 'moods'. Before addressing this question, however, it will first be necessary to say a something about what moods are and how they differ from emotions. 网站原创范文除特殊说明外一切图文作品权归所有；未经官方授权谢绝任何用途转载或刊发于媒体。如发生侵犯作品权现象，保留一切法学追诉权。()，英语毕业论文，英语论文 |
