ارتباط بین انزجار و افکار و اعمال در یک نمونه غیر بالینی

Although obsessive-compulsive patients (OCD) frequently report thoughts and compulsions about dirt and contamination, there is scarce evidence for a relationship between disgust and OCD. This study investigates whether there is a specific relationship between obsessive symptoms and disgust, independently of general psychological distress symptoms. We tested 278 non-clinical volunteers, through the Disgust Scale [Haidt, J., McCauley, C., & Rozin, P. (1994). Individual differences in sensitivity to disgust: a scale sampling seven domains of disgust elicitors. Personality Individual Differences. 16, 701–713], the Padua Inventory — Revised [PI-R; van Oppen, P., Hoekstra, R. J., & Emmelkamp, M. G. (1985). The structure of obsessive-compulsive symptoms.Behaviour Research and Therapy, 33, 15–23], the State-Trait Anxiety Inventory [Spielberger, C. D., Gorsuch, R. L., Lushene, R., Vagg, P. R., & Jacobs, G. A. (1983). Manual for the State-Trait Anxiety Inventory (Form Y). Palo Alto, CA: Consulting Psychologists Press], and the Beck Depression Inventory [Beck, A. T., & Steer, R. (1987). Beck depression inventory scoring manual. The psychological corporation. New York: Harcourt Brace Janovich]. A multiple regression analysis showed a significant positive relationship between disgust and obsessive symptoms, after controlling for gender, age, anxiety, and depression. Washing and checking behaviors were best predicted by disgust, while impulses and rumination were best predicted by anxiety and/or depression. These findings are in line with the hypothesis of a specific relationship between disgust and at least some kinds of obsessive symptoms.

Power and Dalgleish (1997) have suggested that, since patients with obsessive compulsive disorders (OCD) frequently report obsessional thoughts about dirt and contamination (Rachman & Hodgson, 1980), disgust might be implicated in the genesis and maintenance of OCD. In contrast to the traditional and current classification of obsessions and compulsions, some forms of OCD might be primarily based on disgust rather than on fear and anxiety. Based on thought and behavior contents, Phillips, Senior, Fahy and David (1998) argued that cleaning disorders are strictly related to disgust, and checking disorders to anxiety, while Power and Dalgleish (1997) proposed that also checking disorders may be linked to disgust. The evidence for a relationship between disgust and OCD is supported by clinical observations (e.g. Tallis, 1996) and by several empirical studies. For example, OCD patients show a selective impairment in recognizing facial expressions of disgust (Sprengelmeyer et al., 1997). Sensitivity to disgust is positively correlated with the washing sub-scale of the Maudsley Obsessive Compulsive Inventory (Ware, Jain, Burgess, & Davey 1994). Furthermore, there is neuropsychological and neuroimaging evidence of abnormalities in the fronto-striatal regions in OCD (Abruzzese et al., 1997, McGuire, 1995 and Rapaport, 1989). Patients show an increased metabolism and blood flow in orbito-frontal and striatal regions (Breiter & Rauch, 1996). These regions may be involved in the emotion of disgust (Gray et al., 1997, Sprengelmeyer et al., 1996 and Spengelmeyer et al., 1997). In the present study, we investigated whether there is a specific relationship between obsessive symptoms and disgust in a non-clinical population, independently of general psychological distress symptoms (i.e. anxiety and depression). Our aim was to test the hypothesis that the emotion of disgust is substantially related to obsessions and compulsions, and to assess the possibility to discriminate different kinds of obsessions and compulsions based on the perception of disgust.

Table 1 reports mean scores and standard deviations in each test, both for the whole sample and for males and females separately. Table 1. Mean scores (standard deviations) obtained by males, females, and the whole group in each test, and in the Padua Inventory — Revised test (PI-R) sub-scales Males Females All subjects Disgust 15.22 (5.32) 19.20 (4.99) 17.77 (5.45) PI-R total score 26.71 (17.40) 38.99 (24.52) 34.41 (23.04) Impulses 2.19 (2.80) 3.02 (3.28) 2.72 (3.14) Washing 6.53 (5.15) 10.02 (8.19) 8.77 (7.43) Checking 5.16 (3.93) 6.31 (5.29) 5.89 (4.87) Rumination 7.29 (5.05) 10.51 (7.14) 9.36 (6.64) Precision 2.37 (3.24) 2.34 (2.73) 2.35 (2.92) State anxiety 36.20 (9.37) 38.80 (9.99) 37.87 (9.83) Trait anxiety 38.51 (9.19) 42.33 (9.71) 40.96 (9.69) Depression 7.32 (6.42) 8.82 (6.60) 8.28 (6.57) Table options Since females may show higher scores both in the Padua Inventory (Sanavio, 1988, van Oppen, 1992 and Mancini et al., 1999) and in the DS (Power & Dalgleish, 1997), and since age is correlated with PI-R scores (Sanavio, 1988 and Mancini et al., 1999), anxiety, and depression (Pillay & Sargent, 1999), we preliminarily examined the effect of gender and age on the test scores through a multivariate analysis of covariance. Both gender [λ=0.87; F(5,271)=8.3, P<0.001] and age [λ=0.92; F(5,271)=4.9, P<0.001] were significant. Univariate results, correcting for age, showed that females reported higher scores in both the PI-R [F(1,275)=13.43, P<0.001] and the DS [F(1,275)=36.38, P<0.001]. Age was negatively correlated to trait anxiety [F(1,275)=5.88, P<0.05], depression [F(1,275)=9.69, P<0.01], and PI-R scores [F(1,275)=13.43, P<0.001]. Because of gender and age differences, subsequent analyses were conducted separately for males and females, correcting for age. Table 2 reports significant correlations of PI-R scores with disgust, anxiety, and depression scores, partialled for age. Total PI-R scores were positively correlated with disgust only in males, and with anxiety and depression in both males and females. As to the PI-R sub-scales, the impulses sub-scale was not correlated with disgust either in males or females, but was positively correlated with trait anxiety and depression in both males and females, and with state anxiety in males. The washing sub-scale showed a positive correlation with disgust for males and females. The checking and rumination sub-scales presented a positive correlation with disgust only in males. Furthermore, checking was correlated with depression in females, while rumination was correlated with anxiety and depression in both males and females. The precision sub-scale presented a significant correlation only with depression in males. Table 2. Correlations (Pearson coefficient) between the Padua Inventory — Revised test (both for the total score and for each sub-scale score), disgust, anxiety, and depression, in males (M) and females (F), partialled for age (only significant correlations (P<0.05, Bonferroni correction) are displayed) Padua Inventory — Revised Total score Impulses Washing Checking Rumination Precision Disgust M 0.40 – 0.39 0.38 0.31 – F – – 0.29 – – – State anxiety M 0.45 0.47 – – 0.53 – F 0.34 – – – 0.41 – Trait anxiety M 0.45 0.43 – – 0.63 – F 0.51 0.45 – – 0.65 – Depression M 0.55 0.46 – – 0.55 0.35 F 0.52 0.40 – 0.30 0.57 – Table options The specific contribution of disgust in predicting obsessions and compulsions was assessed through a series of hierarchical multiple regression analyses performed on PI-R total scores and on each PI-R sub-scale, after controlling for age, anxiety and depression. In the analyses (1) age was entered first, followed by (2) state and trait anxiety and depression, and (3) disgust. The results of this analysis are shown in Table 3 for males and Table 4 for females. Table 3. Results from hierarchical multiple regression analysis in malesa Step Dependent variables (PI-R) Total score Impulses Washing Checking Rumination Precision Step No. 1 R2 (adjusted) −0.01 0.01 0.01 0.04* −0.01 0.01 β for age 0.07 −0.13 0.11 0.22* 0.03 0.14 Step No. 2 R2 (adjusted) 0.31*** 0.26*** −0.01 0.10** 0.41*** 0.11** β for Age 0.15 −0.07 0.12 0.21** 0.12 0.20* β for State anxiety 0.17 0.27* 0.07 0.12 0.14 −0.06 β for Trait anxiety 0.06 0.07 −0.11 0.04 0.40** 0.03 β for Depression 0.42*** 0.26* 0.15 0.17 0.21 0.37** Step No. 3 R2 (adjusted) 0.41*** 0.26*** 0.13** 0.20*** 0.45*** 0.15** β for Age 0.11 −0.09 0.06 0.21* 0.09 0.17 β for State Anxiety 0.16 0.27∗ 0.05 0.10 0.13 −0.07 β for Trait Anxiety 0.02 0.06 −0.16 −0.01 0.37** −0.01 β for Depression 0.42*** 0.26*∗ 0.14 0.17 0.20 0.37** β for Disgust 0.33*** 0.06 0.39*** 0.33*** 0.21** 0.23* Multiple R 0.66 0.54 0.42 0.49 0.69 0.44 F(5,94) 14.84*** 7.84*** 4.02** 5.95*** 17.04*** 4.58** a Regression of age (step No. 1), anxiety and depression (step No. 2), and disgust (step No. 3) on Padua Inventory — Revised test (PI-R) total scores and on each PI-R sub-scale. * P<0.05. ** P<0.01. *** P<0.001. Table options Table 4. Results from hierarchical multiple regression analysis in femalesa Step Dependent variables (PI-R) Total score Impulses Washing Checking Rumination Precision Step No. 1 R2 (adjusted) 0.15*** 0.05** 0.04** 0.10*** 0.10*** 0.01 β for Age −0.40*** −0.24** −0.22** −0.32*** −0.32*** −0.10 Step No. 2 R2 (adjusted) 0.42*** 0.25*** 0.08** 0.17*** 0.50*** 0.02 β for Age −0.30*** −0.16* −0.18* −0.24*** −0.20*** −0.06 β for State Anxiety 0.02 0.01 0.05 −0.04 0.01 0.05 β for Trait Anxiety 0.27** 0.32** 0.02 0.12 0.43*** 0.01 β for Depression 0.30*** 0.18* 0.19 0.23* 0.24** 0.15 Step No. 3 R2 (adjusted) 0.44*** 0.25*** 0.15*** 0.22*** 0.51*** 0.02 β for Age −0.28*** −0.16* −0.15* −0.24*** −0.20*** −0.06 β for State Anxiety 0.01 0.01 0.04 −0.05 0.01 0.05 β for Trait Anxiety 0.24** 0.33** −0.04 0.07 0.45*** −0.01 β for Depression 0.32*** 0.18* 0.22* 0.26** 0.25** 0.15 β for Disgust 0.17** −0.03 0.27*** 0.23*** 0.06 0.08 Multiple R 0.67 0.52 0.42 0.49 0.72 0.22 F(5,172) 29.03*** 12.72*** 7.182*** 10.84*** 37.30*** 1.78 a Regression of age (step No. 1), anxiety and depression (step No. 2) and disgust (step No. 3) on Padua Inventory — Revised test (PI-R) total scores and on each PI-R sub-scale. * P<0.05. ** P<0.01. *** P<0.001. Table options Disgust was a significant predictor of PI-R total scores in both males and females. Other significant predictors included depression in males, and age, trait anxiety, and depression in females. As to the PI-R sub-scales, impulses were predicted by anxiety and depression but not by disgust, while washing and checking were predicted by disgust but neither by anxiety nor (in males) by depression. Rumination and precision showed a more complex pattern. In males, disgust was a weak but significant predictor of both, together with trait anxiety (for rumination) and depression (for precision). In females, rumination was predicted only by anxiety and depression, while there was no significant predictor of precision.