حساسیت انزجاری و ترس از آلودگی در هراس عنکبوتی و هراس از "جراحت - تزریق - خون"

Disgust has been implicated in the onset and maintenance of blood–injection–injury (BII) and animal phobias. Research suggests that people with these phobias are characterized by an elevated sensitivity to disgust-evoking stimuli separate from their phobic concerns. The disgust response has been described as the rejection of potential contaminants. Disgust-motivated avoidance of phobic stimuli may therefore be related to fears of contamination or infection. The present study compared BII phobics, spider phobics and nonphobics on two measures of disgust sensitivity and two measures of contamination fears. Positive correlations were found between disgust sensitivity and contamination fear. Specific phobics scored higher than nonphobics on all scales and BII phobics scored higher than spider phobics on contamination fear measures. Furthermore, the contamination fear scales were correlated with the blood phobia measure, but not correlated with the spider phobia measure. The results suggest that while both phobias are characterized by elevated disgust sensitivity, contamination fear is more prominent in BII than spider phobia.

A number of investigators have suggested that emotions other than fear may be implicated in the etiology and maintenance of specific phobias (Davey, 1992, Merckelbach et al., 1993 and Tolin et al., 1997). The relative contribution of disgust in animal and blood–injection–injury (BII) phobic behavior has generated considerable theoretical and experimental interest in the empirical literature. For instance, fear ratings of small animals have been found to be positively correlated with characteristics associated with disgust (e.g. dirty, slimy; Merckelbach, van den Hout & van der Molen, 1987). Davey (1992) argued that certain animal fears, especially those animals considered nonpredatory (e.g. spiders, cockroaches, maggots), are mediated by a disease-avoidance process as they are perceived to be associated with dirt and disease-carrying characteristics (Rozin, Haidt & McCauley, 1993). Thus, the disease-avoidance model of animal fears suggests that phobic avoidance is mediated by perceptions of contamination and disease acquisition rather than a fear of being attacked and physically harmed (Matchett & Davey, 1991). Disgust-mediated aversion in various animal phobias, therefore, may be related to the prevention of disease transmission (Rozin and Fallon, 1987 and Rozin et al., 1993). Although disgust may be generally involved in spider phobia, it plays a more prominent role in BII phobia (Page, 1994). Clinical and experimental evidence suggests that exposure to blood–injury stimuli evokes reactions of aversion and nausea (Gross and Levenson, 1993 and Rachman, 1990), especially among BII phobics who are prone to fainting (Kleinknecht, Thorndike & Walls, 1996). Psychophysiological data indicate that exposure to BII phobic stimuli often results in cardiovascular deceleration (Thyer & Curtis, 1985), implying activation of the parasympathetic nervous system (Levenson, 1992). Physiological correlates of the disgust response also reflect parasympathetic activity (Ekman, Levenson & Friesen, 1983). The physiological mechanism of disgust contrasts with the acute sympathetic nervous system reaction (e.g. cardiovascular acceleration) associated with the fear response to phobic stimuli (Gelder & Mathews, 1968). A number of studies have demonstrated that self-report measures of disgust and disgust sensitivity (e.g. Disgust Scale; Haidt, McCauley & Rozin, 1994) are positively correlated with both animal phobias (Matchett and Davey, 1991 and Mulkens et al., 1996) and BII phobia (de Jong and Merckelbach, 1998 and Sawchuk et al., 1997). Heightened disgust sensitivity may therefore serve as a diathesis in facilitating the acquisition of spider and BII phobias (de Jong & Merckelbach, 1998). Furthermore, disgust-evoking properties of phobic stimuli may initiate and exacerbate phobic action tendencies, such as avoidance (Merckelbach et al., 1993). Disgust has been identified as a basic emotion (Ekman, 1992), characterized by well-defined and reliable physiological (e.g. nausea), expressive (e.g. facial), behavioral (e.g. rejection) and interpretive (e.g. contaminant) response components (Rozin et al., 1993). An array of stimuli may evoke reactions of aversion and repulsion. Two general categories of disgust elicitors have been differentiated by Rozin et al. (1993): core and animal-reminder. Core disgust is characterized by a sense of offensiveness and a perceived threat of contamination. Core-disgust elicitors encompass a variety of stimuli such as rotting foods, animal waste products (Angyal, 1941) and fear-relevant, nonpredatory animals associated with dirt and disease (Davey, 1992 and Matchett and Davey, 1991). Animal-reminder disgust refers to the emotional aversion/revulsion of stimuli that prove to be salient reminders of the ‘animalness’ of humans. Blood, veins, connective tissue and muscle tissue serve as potent animal-reminder disgust elicitors as they resemble similar physical properties in humans. Recently, de Jong and Merckelbach (1998) found that disgust elicitors for spider and BII fears are domain-specific. That is, spider fears were associated with core-disgust sensitivity whereas BII fears were associated with animal-reminder disgust sensitivity. It remains possible, however, that in vivo exposure to blood–injury stimuli may potentially evoke core disgust reactions in addition to animal-reminder disgust as such stimuli may carry the potential for contamination and infection. A primary appraisal process associated with disgust is the belief that disgust-elicitors have contamination properties and capabilities (Izard, 1977, Rozin and Fallon, 1987 and Rozin et al., 1993). Fear of contamination is consistent with the disease-avoidance model of animal phobias (Matchett & Davey, 1991). For example, Ware, Jain, Burgess and Davey (1994) found significant correlations between fear-relevant/nonpredatory animals, scores on the Disgust Questionnaire (DQ; Rozin, Fallon & Mandell, 1984) and the obsessive washing subscale of the Maudsley Obsessive–Compulsive Inventory (MOCI; Rachman & Hodgson, 1980). These findings suggest that an individual's fear of disgusting animals may be influenced in part by a sensitivity to experiencing disgust and a general fear of contamination. The purpose of the following study is to provide an exploratory investigation of the relationship between disgust sensitivity and contamination fears in spider and BII phobias. It was hypothesized that phobic participants would score higher than nonphobics on measures of disgust sensitivity. Furthermore, it was predicted that phobic participants would also score higher than nonphobics on obsessive–compulsive subscales assessing contamination obsessions and washing compulsions. An attempt was also made to extend the correlational findings of de Jong and Merckelbach (1998) regarding the domain-specificity of disgust elicitors in spider and BII phobia. These two phobic groups were directly compared on core and animal-reminder disgust domains assessed by the Disgust Emotions Scale (Walls & Kleinknecht, 1996) and the DS (Haidt et al., 1994). Spider phobics were expected to report higher repugnance to core-disgust elicitors while BII phobics were expected to report higher aversion to animal-reminder elicitors.