Emotions and Anxiety (PLE: Emotion)

New Concepts, Methods, and Applications

Marvin Zuckerman, Charles D. Spielberger, Marvin Zuckerman, Charles D. Spielberger

• Éditeur: Psychology Press
• Année: 2015
• ISBN:
  9781317592730
• Édition: 1
• Sujet: Psychology
• Sous-sujet: Emotions in Psychology

First published in 1976, this volume was completely new with original contributions and traces the advances in theory and research on anxiety and emotion of the previous decade. The authors examine the origins of fear, anxiety, and other emotions and consider self-report and psychophysiological approaches to the measurement of anxiety. Also considered are the effects of anxiety on the behaviour of normal and abnormal subjects, and the volume concludes with behavioural approaches to assessment and treatment of anxiety in clinical settings.

Part I
Origins of Fear, Anxiety, and Other Emotions

1
The Facts and Functions of Fear

Stephen J. Suomi
Harry F. Harlow
University of Wisconsin

Fear is not foreign to, any social organism. Although long recognized by behavioral scientists, psychoanalysts, novelists, theologians, politicians, and philosophers as a major factor in the activity of most higher species, it has always remained a rather nebulously defined concept. Some investigators view fear as an emotional state, others focus upon it as a motivational force, while still others use its perception as a stimulus. The term is widely and diversely employed in our everyday language, both as a noun and a verb form—witness Roosevelt's "we have nothing to fear but fear itself'—and as a modifier, it can serve both adjectival and adverbial functions. In short, across a variety of feelings, phenomena, and functions, "fear" seems to be intuitively understood by almost everyone. Yet it seems likely that it is misunderstood by virtually all as well.

There are at least two potential hazards in interpreting the facts and functions associated with fear. First, because it is used in so many different contexts, the term itself has possibly become too broad to have any predictive value. Second, because the emotional condition identified as fear is decidedly unpleasant for most individuals, it is compelling to dismiss it as undesirable, thus ignoring any adaptive function it might serve.

In this chapter we propose to address these points, using data accumulated from years of laboratory study utilizing rhesus monkeys as subjects. It is our contention that fear in monkeys, and most likely in all other primates, is an unlearned response system which soon after emergence into an animal's behavioral repertoire becomes subject to the contingencies of the environment. Further, it is our position that the fear response system has evolved over millions of years and represents a mechanism adaptive in at least two respects: it enhances the probability of survival of individual species members, and it promotes and maintains social structures within the species. In the following pages we will propose a workable definition of fear as exhibited by rhesus monkeys, trace its chronological development, and describe experimental factors which affect its frequency and intensity of occurrence. Finally, we will consider its evolutionary importance in the development and maintenance of social behavior.

Fear as Studied in Nonhuman Subjects: Problems of Generalization

There can be little question that all adult humans are in some way familiar with fear. There can also be little argument over the fact that fear is not an exclusively human property. Considerable anecdotal and experimental evidence has documented fearful-type behavioral reactions by members of numerous species, even though nonhuman subjects obviously could not have verbally reported their inner feelings or states. It seems more than probable that exhibition of fear is a near-universal capability of mammals and possibly other classes of animals.

Numerous studies investigating various aspects of fear have been performed on a variety of species. Although operational definitions of fear have differed considerably from species to species, they usually have involved description of a set of discrete behaviors, typically precipitated by a well-controlled form of stimulation. For example, a common index of fear among most species studied is urination and/or defecation, reflecting a loss of autonomic control following presentation of certain stimuli. The dependent measure is sometimes termed the "bolus count." Other behavior patterns often associated with fear in nonhuman subjects have included withdrawal from stimuli, aversion of the eyes, or emission of particular vocalizations.

These fear behaviors have been carefully monitored following specific "standard" experimental manipulations such as placement in a totally novel environment, subjection to inescapable shock, or exposure to a natural predator. Some researches have achieved "conditioning" of fear, whereby previously neutral stimuli have acquired the same capability to produce fearful behavior patterns as "standard" stimuli following periods of pairing. The classic example of this approach in the human literature has been the study by Watson and Rayner (1920) involving "Little Albert." Here, a previously neutral stimulus, a white rat, was paired with a loud, noxious sound, an unlearned fear stimulus, and soon Albert was petrified at the sight of anything white and furry. Similar studies have been performed using animal subjects, for example, Masserman (1943). The assumption made in these studies is that the "conditioned" fear response is identical to the original form of fear response, even though all one observes is the behavioral concomitant or, more often, only a predefined portion of it.

Other investigators, in efforts to utilize more "objective" measures of what they believe to represent fear, have concentrated on physiological concomitants. Commonly used physiological indices of fear in nonhuman subjects have included changes in autonomic activating systems, such as heart rate, blood pressure, and respiratory rate increases, various patterns of EEGs, vasoconstriction, and secretion of certain hormones. One problem encountered with use of these measures is the fact that they are nonspecific. They all can be elicited, in whole or in part, by a number of stimuli which could be construed to be other than specifically fear inducing. For example, many of the above measures are highly activated during sexual arousal, but one would be hard put to classify such activity as intrinsically fearful for most human or nonhuman subjects. Thus, researchers employing such measures lack the absolute assurance that what they are measuring in their subjects is truly fear. Indeed, they usually prefer to describe their data as indices of "emotionality," or "arousal."

Nevertheless, such problems in definition and measurement have not prevented animal researchers from generalizing their findings to human behavior. For example, results obtained from studies of rats in approach-avoidance paradigms have been employed for explanation of neurotic and psychotic behavior patterns associated with human phobias. Displacement behaviors obtained in fish and birds by ethologists regularly appear as explanations of human activity in stressful situations (Lorenz, 1965). Behavior patterns described as representing "experimental neurosis" in nonhuman mammals have been used to explain human patterns of psychopathology (Liddell, 1947). Tonic immobility observed in numerous nonmammalian species has been related to human catatonia, catalepsy, and cataplexy by several investigators (Gallup & Maser, 1974). In each case, the reactions of nonhuman subjects to manipulations conceived by the experimenters to be fear inducing in one way or another have been recorded, and the long-term consequences of such manipulations have been posited as models for various human psychopathologies.

Such generalization of research findings obtained from nonhuman subjects to human characteristics and predicaments rests upon at least two basic assumptions. The first involves the belief that these behaviors observed in nonhuman subjects are indeed akin to human-like fear, if not identical to human fear itself. The second assumption lies in the feeling that the procedures involved in production of these behavioral forms mimic the etiology of the human disorders. Of course, both of these assumptions are not beyond question, but testing their validity is far from a simple matter, because verbal reports in animals are nonexistent and because there is a paucity of rigorous etiological data for most human psychopathologies.

We, too, have been engaged in nonhuman research at Wisconsin, much of it directed toward uncovering relationships which hold for humans as well as for the rhesus monkeys we study. Out of necessity, we have been acutely aware of the problems inherent in the generalization of findings from one species to another, Gluck, & Suomi, 1972), and have thus found it profitable to establish criteria which our data must meet in order to generalize with accuracy rhesus monkey facts and functions to humans or to other species. These criteria have been described and discussed elsewhere in detail (McKinney & Bunney, 1969), but three of those most important can be mentioned. First, the behavior patterns thought to manifest functions that transcend species ought to be similar in each species studied. In other words, if the behaviors associated with intense fear in humans can be found in the monkey's behavioral repertoire, one is on stronger grounds in proclaiming generalization of fear reactions from man to monkey than if similar behaviors do not exist.n

Second, the case for generalization of findings from one species to another is necessarily strengthened if the manipulations which produce the activity in question are similar or identical across species. A stimulus such as a live snake usually produces withdrawal and vocalizations in some humans and is often accompanied by verbal reports of fear. The same stimulus produces similar behaviors in monkeys, which obviously cannot verbalize any fear. But the inference that fear exists in these monkeys is compelling.

A final criterion employed to justify particular generalizations involves the nature of manipulations or procedures which alleviate or attenuate a system of response. If these are similar across species, one is more certain of the generalization. For example, a human infant who stops crying when picked up by its mother is likely exhibiting the same phenomenon as a monkey infant who stops screeching when it is picked up by its own mother.

In sum, one can establish criteria for the validity of cross-species generalization. When these criteria are met, generalization becomes appropriate. When they are not met in full, generalization becomes suspect. At this point, one might reasonably ask, "why generalize?" What is the purpose of cross-species generalization?

We can readily point out what we consider to be two extremely important functions of generalization, particularly from monkey to man and vice versa. The first is simple and direct: certain researches are impossible to perform on human subjects for either ethical or practical reasons—sometimes both. Some of these researches can be successfully carried out with nonhuman primate subjects, assuming that generalization is appropriate. In these cases it is possible to learn facts about human behavior which could not be properly pursued via human research.

The second reason for generalizing is not as readily apparent. If findings obtained on one species, for example, the rhesus monkey, can be generalized to another species, for example, Homo sapiens, then by definition the findings do not reflect a system of behavior or function which is exclusive of a single species. If, for example, it can be shown that rhesus monkeys react with fear-associated behaviors to a certain class of social stimuli which elicit fear responses in humans, then it cannot be maintained that reactivity to that class of stimuli is an exclusively human disposition. Thus, recent work suggesting that chimpanzees possess the capacity to interpret and communicate syntactual concepts seriously undermines previously held notions concerning the uniqueness of certain aspects of human language (Gardner & Gardner, 1974; Premack, 1971; Rumbaugh, Gill, &von Glaserfeld, 1973).

Continuing this theme, if a set of behaviors or functions can be discovered to exist in more than one reasonably related species, then it is likely that the phenomena possess some evolutionary significance. If one takes evolutionary theory seriously, then he or she is unlikely to attribute the same constellation of behaviors in reaction to the same stimuli across more than one species to mere chance. Rather, one is more apt to conclude that the capability to react in the given manner now has, or had at one time, adaptive consequences which increase the probability of individual survival and/or species propagation. Discovery of similarities of phenomena across species will invariably enhance the acknowledged evolutionary importance of those phenomena (Hinde, 1974).

we have included this brief discussion of generalization of data from one species to others because we believe it is basic to the material which follows. Specifically, data will be presented concerning the appearance and development of fear responses in monkeys. Similarities between these data and human data will be pointed out, and some conclusions will be offered regarding the evolutionary significance of fear reactions for social and nonsocial development and survival.

Stimuli and Responses Associated with Fear in Rhesus Monkeys

As previously pointed out, one cannot approach the study of fear in nonhuman primates by asking monkeys what makes them frightened, but this does not preclude investigation of such phenomena. Rather, study of fear in rhesus monkeys has been accomplished by "asking" the subjects nonverbally which stimuli elicit fear, and the monkeys' answers usually are behavioral responses. What are these fear stimuli, and what are the resulting responses?

Stimuli which elicit fear responses in rhesus monkeys can be generally divided into two classes: those which are innately fearful, and those which yield fear behaviors only after associative learning. The former covers a wide range of stimuli, but surprisingly for rhesus monkeys, natural predators apparently do not fall into this group. Wild-born monkeys rapidly develop a healthy respect for animals such as tigers and leopards which might endanger their existence, but the evidence suggests that this tendency may be learned. For example, Joslin, Fletcher, and Emlen (1964) studied the reactions of feral-born rhesus monkeys to live bull snakes and inanimate models varying in the degree they resembled the real snakes. All but a few of the subjects showed clear fear behaviors in the presence of the snakes and those stimuli which most closely approximated them. Such behaviors were not exhibited when neutral stimuli such as wooden cubes were presented. In sharp contrast, monkeys who had been born and raised in the laboratory showed no fear of either animate snakes or their closest inanimate models. The authors concluded that fear of snakes was not an inherited tendency of rhesus monkeys and that most likely it was acquired via observational learning, a capability well within the cognitive limits of the genus (Miyadi, 1959; Riopelle, 1960).

These and similar findings have contributed support to the theoretical position of Klopfer (1962) and more recently Stephenson (1975) regarding the evolution of fear behavior. They believe that prewired sensitivity to specific stimulus patterns could be adaptively harmful if the species evolved in an environment where natural predators were widespread in range and turnover. In other words, if predators changed more rapidly than genes, the species would be in trouble. Inasmuch as rhesus monkeys and most higher primates had ancestors during an epoch when this was the case over the ancestors' ranges, it is intuitively compelling to accept the position that most predatory-based fears are learned. This principle does not necessarily hold for all animals. Most avian species, for example, have specific stimuli such as predatory birds which are innate elicitors of fear behavior. With most primates this is apparently not the case.

This does not mean that there exist no stimuli which can produce fear behavior independent of experience. The group of animals most able to produce fear responses which have no basis in learning turns out to be the...

Table des matières

• Cover
• Half Title
• Title
• Copyright
• Original Title
• Original Copyright
• Contents
• Preface
• PART I: ORIGINS OF FEAR, ANXIETY, AND OTHER EMOTIONS
• PART II: THE MEASUREMENT OF ANXIETY
• PART III: EFFECTS OF ANXIETY ON NORMAL AND ABNORMAL BEHAVIOR
• PART IV: THE TREATMENT OF AXIETY
• Author Index
• Subject Index