Differentiating between memory and interpretation biases in socially anxious and nonanxious individuals

Behaviour Research and Therapy 42 (2004) 155–171 www.elsevier.com/locate/brat

Differentiating between memory and interpretation biases in socially anxious and nonanxious individuals Jennifer R. Brendle ∗, Amy Wenzel Department of Psychology, University of North Dakota, Grand Forks, ND 58202-8380, USA Received 2 August 2002; received in revised form 17 March 2003; accepted 23 March 2003

Abstract Although individual cognitive biases toward threat in social anxiety are well established, few studies have examined the manner in which cognitive biases work in conjunction. In the present study, socially anxious (n = 54) and nonanxious (n = 58) individuals read 10 passages consisting of positive social or evaluative, negative social or evaluative, and neutral content and completed two cognitive tasks assessing memory of factual details and interpretation immediately and after 48 h. Socially anxious and nonanxious individuals did not differ in their memory for details presented in the passages. However, they made less positive and more negative interpretations of details included in the passages, particularly in positive passages that were self-relevant and particularly in positive passages after the delay. After including depression, state anxiety, and trait anxiety as covariates, biased interpretation of positive passages after the time delay remained significant, but biased interpretation of the self-relevant, positive passages did not. It is concluded that socially anxious individuals are characterized by accurate memory of threatening, factual material, but that they impose a biased interpretation upon that material, especially after some time has passed.  2003 Elsevier Ltd. All rights reserved. Keywords: Social anxiety; Memory bias; Interpretation bias; Cognition

Several cognitive models of social phobia theorize that anxious individuals process information in a biased fashion (e.g. Clark & Wells, 1995; Rapee & Heimberg, 1997). Although these theories suggest that attentional biases toward perceived threat and the interpretation of ambiguous stimuli as dangerous are the primary biases that characterize socially anxious individuals, they also posit that exaggerated memories of threatening experiences shape maladaptive schemata that drive these processing distortions. Several empirical studies have found evidence confirming that socially ∗

Corresponding author. Tel.: +1-701-777-9275. E-mail address: [email protected] (J.R. Brendle).

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anxious individuals attend selectively to threatening information (e.g. Hope, Rapee, Heimberg, & Dombeck, 1990; Mattia, Heimberg, & Hope, 1993; Mogg, Mathews, & Eysenck, 1992) and interpret ambiguous information in a negative fashion (e.g. Amir, Foa, & Coles, 1998; Constans, Penn, Ihen, & Hope, 1999). However, evidence for enhanced memory for threatening stimuli is mixed. Memory for threatening stimuli in socially anxious individuals has been investigated using several different explicit and implicit memory methodologies. Many studies examining explicit memory using single threatening and neutral words have failed to uncover evidence for a memory bias toward threat in socially anxious individuals (e.g. Becker, Roth, Andrich, & Margraf, 1999; Cloitre, Cancienne, Heimberg, Holt, & Liebowitz, 1995; Rapee, McCallum, Melville, Ravenscroft, & Rodney, 1994). That is, these studies show that socially anxious individuals are no more likely than nonanxious individuals to recall single words relating to social or evaluative experiences or to a greater degree than neutral single words. On the other hand, a few studies have reported evidence for the enhanced recall of negative self-relevant adjectives in socially anxious individuals. For example, Claeys (1989) found that socially anxious individuals recalled a greater number of self-descriptive unlikable trait words than nonanxious individuals. Similarly, Breck and Smith (1983) reported that socially anxious individuals demonstrated enhanced memory for negative self-descriptive adjectives; however, the differences between the two groups remained only when the socially anxious individuals were anticipating interaction. Still other studies have found evidence for the presence of biases using paradigms different than those using single word stimuli, but the biases proceeded in different directions. Specifically, Lundh and Ost (1996) reported that socially anxious individuals were more likely to recognize critical faces than accepting faces, a pattern opposite to that demonstrated by nonanxious individuals, whereas Wenzel and Holt (2002) indicated that socially anxious individuals recalled fewer units from threatening prose passages than nonanxious individuals. In addition, some researchers have incorporated an element to simulate the occurrence of actual threat into their investigations of explicit memory bias toward threat in social phobia. For example, Mansell and Clark (1999) reported an explicit memory bias against the recall of positive public self-referent words in individuals with social phobia that was only demonstrated when there was the expectation of having to give a speech. Although this area of research needs further investigation, Mansell and Clark (1999) posed the alternative hypothesis that explicit memory biases in individuals with social phobia are against positive stimuli rather than toward negative stimuli, and furthermore, that anxious activation plays a crucial role in invoking these biases in socially anxious individuals (cf. Breck & Smith, 1983). The implicit memory literature is no easier to interpret. Although Lundh and Ost (1997) uncovered evidence for an implicit memory bias toward threat only when they analyzed their data post-hoc as a function of social phobia subtype, Amir, Foa and Coles (2000) reported strong evidence for an implicit memory bias toward threat using their white noise methodology. Thus, similar to the explicit memory literature, there is mixed evidence with regard to whether individuals with social phobia demonstrate biased implicit memory for threat. One clue as to the mechanism that might underlie these mixed results is suggested by findings reported by Burke and Mathews (1992). In this study, participants were cued with neutral single words and asked to retrieve the first personal memory that came to mind. After participants identified a memory, they supplied one adjective that best described the associated mood rated its associated intensity. Their results suggested that generally anxious individuals were more likely

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to retrieve ‘nervous’ memories and less likely to retrieve ‘pleased’ memories than nonanxious individuals. However, these group differences disappeared when raters who were naı¨ve to group status coded the emotional tone of the memories. These results suggest the intriguing possibility that some types of anxious individuals are characterized by accurate memories of threatening material coupled with a tendency to interpret these events in a more negative and/or less positive manner than nonanxious individuals. It is possible that this mechanism also characterizes socially anxious individuals, as the explicit memory studies including stimuli that left the most room for interpretation (i.e. emotional faces, prose passages) were those that found memory biases in anxious participants. In contrast to the mixed results that characterize the literature on memory biases in social anxiety, there is clear evidence that socially anxious individuals interpret ambiguous material in a negative manner. For example, Stopa and Clark (2000), presented individuals with social phobia, individuals with another anxiety disorder, and nonanxious participants with ambiguous social and nonsocial events, as well as with unambiguous, slightly negative events. Participants answered open-ended questions, ranked the likelihood of provided interpretations, and completed ratings of the degree for which they believed the interpretations. Results suggested that the individuals with social phobia were more likely than the nonanxious participants to interpret ambiguous social events negatively and to catastrophize unambiguous, slightly negative social events. In another study, Amir, Foa and Coles (1998) presented individuals with generalized social phobia, individuals with obsessive compulsive disorder (OCD), and nonanxious individuals with 15 scenarios that were socially relevant (e.g. going on a date) and seven that were non-socially relevant (e.g. paying a monthly cable bill), each followed with a positive, negative, and neutral interpretation, in which participants were asked to rank order the three interpretations according to the likelihood that each would come to their mind, as well as to a typical person’s mind. Results indicated that individuals with social phobia were more likely to choose a negative interpretation for ambiguous social scenarios than individuals with OCD and nonanxious individuals only when they judged what would come to their mind. Moreover, Roth, Antony and Swinson (2001) instructed individuals with social phobia and nonanxious individuals to complete either a questionnaire assessing how their own anxiety symptoms are interpreted by others or a questionnaire assessing how they typically interpret anxiety symptoms in others. Results indicated that individuals with social phobia were more likely than nonanxious individuals to believe that others interpreted anxious symptoms as being indicative of intense anxiety or a psychiatric condition and less likely to believe that others interpreted these symptoms as being indicative of a normal, physical state. Thus, results from these studies suggest that individuals with social phobia are more likely to interpret information pertaining to themselves as negative than information pertaining to others. In a design similar to that of Amir et al. (1998); Constans, Penn, Ihen and Hope (1999) instructed socially anxious and nonanxious undergraduates to read an ambiguous vignette depicting a blind date between two college-aged students and complete a 19-item questionnaire assessing their interpretation of events from the story. Items contained either positive or negative interpretations, and participants rated how strongly they agreed with each item using a sevenpoint Likert-type scale. Negative items were reversed scored so that scores above the midpoint would reflect positive interpretations of the scenario. Results indicated that the socially anxious individuals rated interpretation items lower than nonanxious individuals, providing evidence for biased interpretation of threat-related material in social anxiety. However, the authors noted that

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the mean ratings of the socially anxious individuals fell just slightly above the mid-point of the scale at approximately 4.58, raising the possibility that interpretation biases in social anxiety reflect a lack of positivity rather than increased negativity. In all, there is mixed evidence that socially anxious individuals demonstrate biased memory for social threat information, but there is robust evidence that they interpret it in a negative manner. Based on the results of Burke and Mathews (1992), one explanation for the state of this literature is that these individuals are characterized by accurate memory for threatening events, but impose a biased interpretation on that material, particularly when the material is self-relevant. To investigate this possibility, socially anxious and nonanxious individuals in the present study completed tasks assessing their memory for and interpretation of the same material. Self- and other-relevant positive and negative prose passages describing social and evaluative situations and neutral passages were used to investigate the nature of these biases. Memory biases were evaluated in socially anxious individuals through questions assessing the accuracy of factual details from the passages. Both negative and positive interpretation biases were assessed by asking participants to rate the likelihood of positive, negative, and neutral explanations for the events in the passages rather than asking them to select only one of the options as being most likely. The predictions of this study were as follows. Based on the nature of the literature pertaining to memory biases in social phobia, it was expected that socially anxious individuals would demonstrate accurate recall of threat-related information. However, consistent with the literature pertaining to interpretation biases in social phobia, it was expected that socially anxious individuals would interpret these events more negatively, as well as less positively, than nonanxious individuals. Additionally, it was predicted that such biased interpretations would be especially evident in passages that were self-relevant (cf. Amir et al., 1998). Moreover, it was predicted that biased interpretations reflected in likelihood ratings of both negative and positive explanations would be important in distinguishing between groups, such that socially anxious individuals would interpret social and evaluative passages in an equally more negative and less positive manner. 1. Method 1.1. Participants Two samples were used in the present study: 54 individuals with self-reported social anxiety and 58 individuals without self-reported social anxiety. Participants were undergraduate introductory psychology students from the University of North Dakota who received course or extra credit for completing the study. Participants had a mean age of 20.0 years, 70.5% were female, 93.8% were Caucasian, and 74.1% were freshman or sophomore students. Demographic variables did not differ between groups. Participants were identified through a complex screening process. To determine eligibility, 1781 participants were administered the fear of negative evaluation scale (FNE; Watson & Friend, 1969) and the social avoidance and distress scale (SAD; Watson & Friend, 1969) in mass testing sessions over the course of two semesters. Individuals scoring at least one standard deviation above the mean on both inventories were identified for the socially anxious group (FNEⱖ21; SADⱖ13), and individuals scoring at least one standard deviation below the mean on both inven-

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tories were identified for the nonanxious group (FNEⱕ4; SADⱕ1). Two screening measures were used to ensure that groups would remain valid despite regression to the mean at the time of the experimental session. One hundred and sixty-three individuals (9.2% of the total sample; mean FNE = 25.8; mean SAD = 18.2) met criteria to be contacted for participation in the socially anxious group; 167 individuals (9.4% of the total sample; mean FNE = 2.0; mean SAD = 0.5) met criteria to be contacted for participation in the nonanxious group. Eligible participants were contacted by telephone by the first author. A total of 60 individuals identified as socially anxious and 60 individuals identified as nonanxious agreed to participate and attended the experimental sessions. All participants completed the FNE and the SAD a second time to assess the degree to which scores on these two measures regressed toward the mean. Data from socially anxious individuals were excluded from analyses if their scores on either of these measures during the second assessment dropped below the mean obtained for the initial screening sample, and data from nonanxious individuals were excluded from analyses if their score on either the FNE or SAD during the second assessment were above the mean obtained for the initial screening sample. Data from six socially anxious and two nonanxious individuals were excluded from analyses for these reasons. There were no differences in demographic variables between individuals whose data were included in the analyses and individuals whose data were excluded from the analyses. 1.2. Stimuli Stimuli consisted of 10 passages: four scenarios relating to a social or evaluative situation with a positive valence (social-positive), four scenarios relating to a social or evaluative situation with a negative valence (social-negative), and two neutral scenarios (neutral). Half of the passages were written in the first person perspective to be self-relevant (self-perspective), and half were written in the third person perspective to be other-relevant (other-perspective). Each passage was equated for number of words, number of sentences, average sentence length, and reading level using a formula developed for testing the grade-level difficulty of reading materials (Dale & Chall, 1948). The average number of words was 293 (range, 278–307), and the average sentence length was 10.47 (range, 9.93–10.96) words. Each passage contained 28 sentences and was equated to a fifth to sixth grade reading level. Additionally, each passage had a similar composition. The 10th and 19th sentences of the social or evaluative passages contained a statement describing an emotion (e.g. ‘You felt excited.’). Neutral passages contained sentences describing concrete actions or events in the same places as these sentences. In the social-negative passages, the 13th sentence contained the description of a physiological reaction (e.g. ‘Your face turned red.’). Social-positive and neutral passages contained a sentence describing a concrete action or event in this same location. In all passages, the 14th and 22nd sentences contained statements referring to cognitions (e.g. ‘You thought you were making a good impression.’). All remaining sentences in the passages contained statements about a concrete action or event (e.g. ‘You opened the door.’). Normative ratings confirmed that passages corresponded to their expected valence and content. Undergraduate psychology research students provided ratings for each of the passages for pleasantness (1, extremely unpleasant; 7, extremely pleasant) and degree of relatedness to social or evaluative situations (1, not at all related; 7, stereotypical). Norming indicated that social-

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positive passages were significantly more pleasant than neutral passages, t(19) = 6.42; P ⬍ 0.001, and social-negative passages, t(19) = 17.93; P ⬍ 0.001. In addition, social-negative passages were significantly more unpleasant than neutral passages, t(19) = 14.39; P = 0.001. Norming also indicated that social-positive and social-negative passages were not different from each other in their relatedness to social or evaluative situations, t(19) = ⫺1.52; P = ns. However, neutral passages were significantly less related to social or evaluative situations than both positive-social, t(19) = ⫺4.85; P ⬍ 0.001, and negative-social, t(19) = ⫺5.00; P ⬍ 0.001, passages. A Latin square counterbalancing scheme was used to create 10 orders for the presentation of passages, so that each passage appeared in each position and preceded and followed different passages in each order. Participants were randomly assigned to one of the 10 orders, and there were equal number of participants from the two groups who were assigned to each order. 1.3. Cognitive tasks 1.3.1. Memory task The memory task consisted of 12 questions requiring recall of factual details presented in each passage (e.g. ‘At what time did the woman look at her watch?’; ‘How long did John spend getting ready for his interview?’; ‘What room did you clean first?’).1 The primary reason to assess for only the memory of factual details and not more global, negative and positive information (i.e. emotional tone) was so that the memory task would be distinct from and not confounded by the participant’s interpretations. Normative ratings were obtained to characterize the difficulty level of each question and the importance of each question to the main idea of the passage. Undergraduate psychology research students rated these dimensions on seven-point Likert-type scales (1, extremely easy or unimportant; 7, extremely difficult or important). Results indicated that all questions were characterized by similar levels of importance and difficulty regardless of the valence of the passage to which the questions corresponded (mean difficulty, 4.88 [S.D. = 0.74]); mean importance, 4.38 [S.D. = 0.69]). For each passage, six questions comprised an immediate recall test administered immediately after the presentation of each passage, and six questions comprised a test of delayed recall, which was administered approximately 48 h later. In all, participants answered a total of 60 questions on each occasion, with six questions corresponding to each passage. A counterbalancing schedule was used to determine the set of questions contained in the immediate and delayed tasks, so that half of the participants received one set of questions for the immediate task, and half of the participants received that same set of questions for the delayed task. Norming indicated that there was no difference in the difficulty or importance level of questions assigned to the different sets. Memory tasks were scored by two blind research assistants for accuracy, such that each item was regarded as correct (1 point), partially correct (1/2 point), or incorrect (0 points).2 Consensus scoring meetings were held every 2 weeks to prevent rater bias and drift. The final reliability for this scoring scheme was 97%.

1 2

The memory tasks are available from the first author upon request. The scoring manual is available from the first author upon request.

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1.3.2. Interpretation task The interpretation task consisted of eight questions requiring the interpretation of factual details presented in the passages (e.g. ‘At 11 o’clock, the woman looked at her watch and told Matt she needed to go because…’; ‘John spent 2 hours getting ready for the interview because…’; ‘You decided to clean your bedroom first because…’).3 For each passage, four questions comprised an immediate interpretation test administered immediately after the presentation of each passage, and four questions comprised a test of delayed interpretation, which was administered approximately 48 h later. In all, participants responded to 40 interpretation questions on each occasion, with four questions corresponding to each passage. A counterbalancing schedule was used to determine the set of questions contained in the immediate and delayed tasks, so that half of the participants received one set of questions for the immediate task and half of the participants received that same set of questions for the delayed task. Three of the questions in the immediate task and three questions in the delayed task asked for the interpretation of details included in the passages that were also assessed in the memory task. The fourth question in both the immediate and the delayed tasks asked for the interpretation of the question, ‘What will happen next?’. For each question in both the immediate and delayed tasks, three possible interpretations, presented in random order, for passage details were provided. One interpretation characterized a positive explanation, one interpretation characterized a negative explanation, and one interpretation characterized a neutral explanation to answer each question. Participants rated the likelihood of each of the three provided interpretations using a nine-point Likert-type scale (1, very unlikely; 9, very likely). To confirm that the positive, negative, and neutral options corresponded to their expected valence, undergraduate psychology research students rated the pleasantness of each interpretation on a seven-point Likert-type scale (1, extremely unpleasant; 7, extremely pleasant). Results indicated that positive interpretations were indeed more pleasant than neutral options, t(19) = 9.56, P ⬍ 0.001, which were in turn more pleasant than negative options, t(19) = 11.24, P ⬍ 0.001. The two sets of questions did not differ in the degree of pleasantness associated with the three options. 1.4. Procedure Participants attended three separate experimental sessions. In the first session, participants completed the SAD, FNE, state-trait anxiety inventory (STAI; Spielberger, Gorsuch, & Lushene, 1970), Beck depression inventory (BDI; Beck, Ward, Mendelsohn, Mock, & Erbaugh, 1961), Nelson–Denny reading test (NDRT; Nelson & Denny, 1973), and the Shipley Institute of Living scale-vocabulary test (SILS; Shipley, 1946). In a second session scheduled within the same week, participants completed the immediate memory and interpretation tasks. Participants read 10 passages, one at a time, that were presented by means of a computer. Participants were required to press a key to move from sentence to sentence and could not go back to previous sentences. Participants subsequently completed the immediate memory task in which they were asked to recall details from the passage they had just read. Next, participants completed the interpretation task, in which they rated the likelihood of positive, negative, and neutral explanations for the

3

The interpretation tasks are available from the first author upon request.

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same passage events. Participants completed one practice trial with the initial passage and cognitive tasks and then proceeded to complete the 10 experimental passages and tasks. Participants read each passage and completed the corresponding cognitive tasks in the same manner until all 10 passages had been presented. After approximately 48 h, participants returned to complete the delayed experimental session. Participants were read instructions directing them to answer each question in the tasks to his or her best recollection. Participants were presented with the delayed memory and delayed interpretation tasks in the same order as the immediate tasks were presented in the previous session.

2. Results Only those interactions involving the group variable are reported, as all hypotheses tested in this study involved differences between the two groups. 2.1. Participant characteristics Group responses on the self-report inventories, NDRT, and the SILS are presented in Table 1. Socially anxious individuals scored higher than nonanxious individuals on all self-report inventories measuring symptoms of emotional disturbance. In general, these results suggest that group assignment was valid, as individuals in the socially anxious group reported significantly higher levels of social anxiety than nonanxious individuals. In addition, the socially anxious individuals also reported higher levels of general anxiety and depression than nonanxious individuals. On the measures of cognitive functioning, the NDRT and the SILS, there were no differences found between the two groups. Therefore, any significant differences cannot be attributed to differences in reading rate or vocabulary knowledge.

Table 1 Group differences on measures of participant characteristics Socially anxious group (n = 54) FNE SAD STAI-S STAI-T BDI NDRT SILS-V

24.17 17.98 43.72 50.41 13.15 237.54 28.80

(3.78) (5.69) (1.59) (9.19) (9.84) (63.17) (4.22)

Nonanxious group (n = 58) 2.17 0.62 26.31 31.77 2.31 263.83 28.60

(2.33) (1.09) (5.91) (4.24) (3.11) (77.45) (3.11)

t

P

37.37 22.79 10.05 13.94 7.98 ⫺1.96 0.28

0.000 0.000 0.000 0.000 0.000 ns ns

Values in parentheses are standard deviations. FNE, fear of negative evaluation scale; SAD, social avoidance and distress scale; STAI-S, state-trait anxiety inventory-state version; STAI-T, state-trait anxiety inventory-trait version; NDRT, Nelson–Denny reading test; SILS, Shipley Institute of Living scale-vocabulary.

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2.2. Memory task As hypothesized, socially anxious and nonanxious individuals did not differ in the recall of factual information assessed in the memory task. Table 2 displays the mean scores and standard deviations for the two groups on the memory task. A 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) × 2 (passage perspective: self, other) × 2 (time: immediate, delayed) mixed ANOVA with repeated measures on the second, third, and fourth variables was conducted to assess whether memory changed as a function of experimental group, passage valence, passage perspective, or time. Results revealed main effects for passage valence, F(2, 220) = 19.29; P ⬍ 0.001, passage perspective, F(1,110) = 8.47; P = 0.004, and time, F(1,110) = 1549.59; P ⬍ 0.001, that were qualified by a passage valence by passage perspective two-way interaction, F(2, 220) = 11.26; P ⬍ 0.001, and a passage perspective by time two-way interaction, F(1,110) = 8.71; P = 0.004. Although some main effects and interactions were found, there was no main effect for group or group by stimulus interaction. Thus, the two groups were not affected differentially by the passage valence, passage perspective, or time conditions, indicating that there were no differences in memory between the two groups on this task.

Table 2 Mean scores for memory task Passage Positive Immediate Self Other Delayed Self Other Negative Immediate Self Other Delayed Self Other Neutral Immediate Self Other Delayed Self Other

Socially anxious group (n = 54)

Nonanxious group (n = 58)

5.28 (0.57) 5.24 (0.60)

5.35 (0.56) 5.12 (0.59)

2.97 (0.97) 2.93 (0.95)

3.07 (0.92) 3.21 (1.05)

4.91 (0.86) 4.83 (0.76)

4.84 (0.81) 4.81 (0.75)

2.86 (0.82) 2.88 (0.91)

2.64 (0.85) 2.82 (1.01)

5.06 (1.09) 5.27 (0.75)

5.11 (0.89) 5.36 (0.67)

2.69 (1.02) 3.26 (1.19)

2.70 (1.12) 3.32 (1.22)

Values can range from 0–6 and represent the number of questions answered correctly for each passage valence. Values in parentheses are standard deviations.

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2.3. Interpretation task As predicted, the socially anxious individuals and nonanxious individuals differed in their interpretations of both negative and positive social events. Table 3 displays the mean scores and standard deviations for the two groups on the interpretation task. A 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) × 2 (passage perspective: self, other) × 2 (time: immediate, delayed) × 3 (interpretation: positive, negative, neutral) mixed ANOVA with repeated measures on the second, third, fourth, and fifth variables was conducted. Main effects were revealed for group, F(1, 108) = 5.34; P = 0.023, passage valence, F(2, 216) = 147.91; P ⬍ 0.001, time, F(1, 108) = 27.09; P ⬍ 0.001, and interpretation, F(2, 216) = 165.15; P ⬍ 0.001. These main effects were qualified by several significant two-way interactions, including a passage valence by group interaction, F(2, 216) = 3.97; P = 0.022, time by group interaction, F(1, 108) = 7.14; P = 0.009, interpretation by group interaction, F(1, 108) = 26.31; P ⬍ 0.001, passage valence by passage perspective interaction, F(2, 216) = 18.45; P ⬍ 0.001, passage valence by time, F(2, 216) = 10.72; P ⬍ 0.001, passage perspective by time interaction, F(1, 108) = 14.23; P ⬍ 0.001, passage valence by interpretation interaction, F(4, 432) = Table 3 Mean scores for interpretation task

Passage Positive Immediate Self Other Delayed Self Other Negative Immediate Self Other Delayed Self Other Neutral Immediate Self Other Delayed Self Other

Socially anxious group (n = 54)

Nonanxious group (n = 58)

Positive

Negative

Neutral

Positive

Negative

Neutral

7.20 (1.03) 6.84 (0.87)

4.68 (1.58) 4.16 (1.37)

5.50 (0.73) 6.25 (1.19)

7.83 (0.84) 7.14 (0.75)

2.91 (1.33) 2.97 (1.27)

5.51 (0.91) 6.44 (0.84)

7.06 (1.12) 6.85 (1.13)

4.73 (1.90) 4.09 (1.67)

6.00 (0.91) 6.70 (0.84)

7.57 (0.79) 7.19 (0.85)

3.10 (1.45) 3.08 (1.34)

5.71 (0.94) 6.23 (0.79)

4.40 (1.12) 4.51 (1.19)

6.51 (1.41) 7.04 (1.22)

4.72 (1.12) 4.98 (1.11 )

4.61 (1.30) 5.05 (1.39)

5.95 (1.55) 6.12 (1.42)

4.86 (1.16) 5.11 (1.15)

5.82 (1.00) 5.43 (1.28)

5.85 (1.04) 6.74 (1.44)

5.90 (1.16) 5.29 (1.10)

5.77 (1.20) 5.03 (1.41)

5.25 (0.90) 6.23 (1.50)

5.55 (0.84) 5.18 (1.02)

5.97 (1.37) 6.75 (1.17)

5.13 (1.56) 4.30 (1.59)

6.92 (1.27) 6.61 (1.26)

6.35 (1.35) 7.22 (1.04)

4.57 (1.74) 3.54 (1.79)

6.99 (1.06) 6.49 (1.13)

6.40 (1.20) 7.12 (1.20)

5.73 (1.77) 4.53 (1.72)

7.29 (0.97) 6.82 (0.93)

6.63 (1.19) 7.49 (1.01)

4.51 (1.77) 3.40 (1.45)

7.13 (0.95) 6.56 (1.28)

Values can range from 1 to 9 and represent the likelihood (1, very unlikely; 9, very likely) of the provided interpretations for each passage valence. Values in parentheses are standard deviations.

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339.26; P ⬍ 0.001, passage perspective by interpretation interaction, F(2, 216) = 10.15; P ⬍ 0.001, and time by interpretation, F(2, 216) = 23.55; P ⬍ 0.001. These two-way interactions were qualified by significant three-way interactions, including a passage valence by passage perspective by time interaction, F(2, 216) = 5.03; P = 0.008, passage valence by interpretation by group interaction, F(4, 432) = 4.16; P = 0.019, passage valence by passage perspective by interpretation interaction, F(4, 432) = 78.47; P ⬍ 0.001, passage valence by time by interpretation interaction, F(4, 432) = 16.39; P ⬍ 0.001, and passage perspective by time by interpretation interaction, F(2, 216) = 4.85; P = 0.012. Finally, these three-way interactions were qualified by two fourway interactions, including a group by passage valence by passage perspective by interpretation four-way interaction, F(4, 432) = 2.76; P = 0.034, and a group by passage valence by time by interpretation four-way interaction, F(4, 432) = 3.43; P = 0.014. Three-way follow-up analyses broken down by type of interpretation (i.e. positive, negative, neutral) were conducted to evaluate the two significant four-way interactions. Results from each follow-up are described below. Only main effects and interactions involving the group variable will be considered in the interest of parsimony. Alpha levels of 0.025 were adopted for the followup three-way ANOVAs, and alpha levels of 0.01 were adopted for the follow-up tests of simple effects. 2.3.1. Group by passage valence by passage perspective by interpretation interaction: followups The significant group by passage valence by passage perspective by interpretation four-way interaction was evaluated by conducting follow-up ANOVAs broken down type of interpretation. First, a 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) × (passage perspective: self, other) ANOVA was conducted for the positive interpretations. Main effects were found for passage valence, F(2, 216) = 358.36; P ⬍ 0.001, and a trend for passage perspective, F(1, 108) = 4.10; P = 0.045, qualified by a significant passage valence by passage perspective two-way interaction, F(2, 216) = 58.22; P ⬍ 0.001. In addition, a trend toward a main effect was found for group, F(1,108) = 4.61; P = 0.034, meaning that socially anxious individuals generally made less positive interpretations than nonanxious individuals in all passages. Second, a 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) × (passage perspective: self, other) ANOVA was conducted for the negative interpretations. Main effects were found for group, F(1,108) = 25.72; P ⬍ 0.001, passage valence, F(2, 216) = 264.02; P ⬍ 0.001, and passage perspective, F(1, 108) = 14.69; P ⬍ 0.001. The main effects for passage valence and passage perspective were qualified by a significant passage valence by passage perspective two-way interaction, F(2,216) = 76.99; P = 0.012, which was qualified by a group by passage valence by passage perspective three-way interaction, F(2,216) = 4.49; P = 0.012. To evaluate the group by passage valence by passage perspective three-way interaction for negative interpretations, 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) ANOVAs was conducted for the self and other perspectives. In the self-perspective passages, main effects were found for group, F(1,108) = 24.78; P ⬍ 0.001, and passage valence, F(2,216) = 129.01; P ⬍ 0.001, that were qualified by a significant group by passage valence two-way interaction, F(2, 216) = 10.81; P ⬍ 0.001. Follow-up simple effects tests

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revealed that socially anxious individuals made more negative interpretations all passages, but that the magnitude of differences between groups was particularly large for the positive passages. In the other perspective passages, main effects were found for group, F(1, 108) = 22.34; P ⬍ 0.001, and passage valence, F(2, 216) = 286.26; P ⬍ 0.001, but there was no interaction. Socially anxious individuals made more negative interpretations than nonanxious individuals in all passages, and participants made more negative interpretations in negative passages than in positive or neutral passages. Third, a 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) × passage perspective (self, other) ANOVA was conducted for the neutral interpretations. A main effect was found for passage valence, F(2, 216) = 409.06; P ⬍ 0.001, qualified by a passage valence by passage perspective interaction, F(2, 216) = 52.91; P ⬍ 0.001. However, no main effect or interactions for group were found, meaning that there were no differences in the degree to which socially anxious and nonanxious individuals chose neutral options as a function of passage type. In sum, the significant group by passage valence by passage perspective by interpretation fourway interaction suggested that socially anxious individuals were generally less positive and more negative than nonanxious individuals in their interpretations of all passages. However, socially anxious individuals were particularly negative in positive passages in the self-perspective, consistent with the expectation that the strongest interpretation biases would be revealed in the selfrelevant passages.

2.3.2. Group by passage valence by time by interpretation interaction: follow-ups The significant group by passage valence by time by interpretation four-way interaction was evaluated by conducting follow-up ANOVAs broken down type of interpretation. First, a 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) × time (immediate, delayed) ANOVA was conducted for the positive interpretations. Main effects were found for time, F(1, 108) = 50.87; P ⬍ 0.001 and passage valence, F(2, 216) = 358.36; P ⬍ 0.001, and there was a trend toward a significant main effect was found for group, F(1, 108) = 4.61; P = 0.034. These main effects were qualified by a trend toward a group by passage valence by time three-way interaction, F(2, 216) = 3.86; P = 0.026. The three-way interaction was followed-up with 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) ANOVAs for the immediate and delayed recall conditions. In the immediate recall condition, main effects were found for group, F(1, 108) = 9.09; P = 0.003, and passage valence, F(2, 216) = 367.86; P ⬍ 0.001, indicating that socially anxious individuals made less positive interpretations than nonanxious individuals in all passages and that participants rated positive interpretations as more likely for positive passages and least likely for negative passages. In the delayed recall condition, a main effect was found for passage valence, F(2, 216) = 159.86; P ⬍ 0.001, that was qualified by a passage valence by group two-way interaction, F(2, 216) = 5.93; P = 0.007. Follow-up simple effects tests revealed that socially anxious individuals made less positive interpretations in the positive passages, t(108) = ⫺2.41; P = 0.018, than nonanxious individuals, but that the two groups did not differ in their positive interpretations in the negative and neutral passages.

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Second, a 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) × time (immediate, delayed) ANOVA was conducted for the negative interpretations. Main effects were found for group, F(1, 108) = 25.72; P ⬍ 0.001, and passage valence, F(2, 216) = 264.02; P ⬍ 0.001, that were qualified by a passage valence by time two-way interaction, F(2, 216) = 7.88; P = 0.001. The passage valence by time two-way interaction was in turn qualified by a trend toward a group by passage valence by time three-way interaction, F(2, 216) = 3.80; P = 0.031. The three-way interaction was followed-up with a 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) ANOVA in the immediate recall condition and a 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) ANOVA in the delayed recall condition. In the immediate recall condition, main effects were found for group, F(1, 108) = 23.94; P ⬍ 0.001, and passage valence, F(2, 216) = 215.76; P ⬍ 0.001, which were qualified by a group by passage valence two-way interaction, F(2, 216) = 5.78; P = 0.007. Follow-up simple effects tests revealed that socially anxious individuals made more negative interpretations than nonanxious individuals in the positive passages, t(108) = 6.24; P ⬍ 0.001, and negative passages, t(108) = 3.17; P = 0.002, but not in the neutral passages. In the delayed recall condition, main effects were found for group, F(1, 108) = 22.58; P ⬍ 0.001, and passage valence, F(2, 216) = 159.68; P ⬍ 0.001, which were qualified by a group by passage valence two-way interaction, F(2, 216) = 4.93; P = 0.009. Follow-up simple effects tests revealed that socially anxious individuals made more negative interpretations than nonanxious individuals in the positive passages, t(108) = 4.57; P ⬍ 0.001, negative passages, t(108) = 3.03; P = 0.003, and neutral passages, t(108) = 3.99; P ⬍ 0.001, than nonanxious individuals. However, the difference between groups was much larger in the positive and neutral passages as than in the negative passages. Third, a 2 (group: socially anxious, nonanxious) × 3 (passage valence: positive, negative, neutral) × (time: immediate, delayed) ANOVA was conducted for the neutral interpretations. Main effects were found for passage valence, F(2, 216) = 409.06; P ⬍ 0.001, and time, F(1, 108) = 36.78; P ⬍ 0.001, that were qualified by a group by time two-way interaction, F(1, 108) = 9.84; P = 0.002, and a passage valence by time two-way interaction, F(2, 216) = 5.59; P = 0.006. Follow-up simple effects tests revealed a trend indicating that socially anxious individuals were more likely than nonanxious individuals to rate neutral interpretations as being likely in all passages in the delayed recall condition, t(108) = 2.04; P = 0.044. This finding is difficult to interpret, as there is no theoretical reason to explain why socially anxious individuals would make more neutral interpretations than the nonanxious individuals after some time has passed. Although groups differences as a function of time were not hypothesized, the significant group by passage valence by passage time by interpretation four-way interaction suggests that socially anxious individuals were less positive in their interpretations than nonanxious individuals of all passages in the immediate recall condition and in the positive passages in the delayed recall condition. In addition, socially anxious individuals were more negative than nonanxious individuals in their interpretations of positive and negative passages in the immediate recall condition and in all passages the delayed recall condition, although the magnitude of this difference was smaller for negative passages than for positive and neutral passages. Also, socially anxious individuals were more likely than nonanxious individuals to make neutral interpretations in all passages in the delayed recall condition.

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3. Discussion The primary goal of the present study was to distinguish between memory and interpretation biases in socially anxious individuals with the goal of determining whether these biases work together to create information processing distortions in the presence of threatening stimuli. The majority of previous studies have found evidence for an interpretation bias in social anxiety, such that socially anxious individuals interpret social or evaluative situations either more negatively (e.g. Amir et al., 1998) or less positively (Constans et al., 1999) than nonanxious individuals. In addition, results from Amir et al.’s (1998) and Roth et al.’s (2001) studies indicate that this bias is specific to self-relevant information. On the other hand, evidence for enhanced memory for threatening material in socially anxious individuals is equivocal. Thus, the precise nature of interpretation and memory biases in social anxiety is relatively unclear. It is possible that memory biases are found only in studies that incorporate stimuli that leave room for a negative interpretation by anxious participants. To examine this possibility, socially anxious and nonanxious participants completed tasks assessing their memory and interpretation of positive and negative passages describing social and evaluative situations and neutral passages. The critical piece of the design was that participants first provided their memory for passage details of and then provided their interpretation of the same passage details. Thus, this study adds uniquely to the literature because its design allows one to examine the manner in which memory and interpretation processes work in conjunction. The results supported our prediction that socially anxious individuals would recall details of threatening prose passages as accurately as nonanxious individuals, but that they would interpret that same material in a biased manner. Although in all passages they were more likely to rate positive interpretations lower and negative interpretations higher than nonanxious individuals, they were particularly biased for interpretations of details from positive self-relevant passages and positive passages after a 48-h delay. Results from this study suggested that socially anxious individuals are not characterized by enhanced explicit memory for threatening material. In addition, results from this study clarified the nature of interpretation biases in social anxiety. Although Amir et al. (1998) provided evidence suggesting that socially anxious individuals interpret ambiguous social and evaluative material in a negative manner, Constans et al. (1999) raised the possibility that their bias lies in being less positive rather than more negative than nonanxious individuals. Our results suggest that both processes are at work, although they might differ in subtle ways. Specifically, socially anxious individuals generally rated negative interpretations as being more likely than nonanxious individuals, but this bias was particularly pronounced in the self-relevant positive passages. In contrast, they generally rated positive interpretations as being less likely than nonanxious individuals, but this bias was particularly pronounced when details from positive passages were interpreted after 48 h. Thus, negative interpretation biases emerged as a function of passage perspective, and positive interpretation biases emerged as a function of time. We were able to uncover this differentiation because, unlike other studies examining interpretation biases in anxiety disorders, participants rated the likelihood of all possible interpretations instead of choosing the more likely one, and because we included a delayed time period. In fact, this is the only known study to examine immediate and delayed interpretation biases in anxious and nonanxious individuals. In addition to performing the analyses reported in the Results section, all main analyses were

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also performed using depression, state anxiety, and trait anxiety as covariates. Although the results pertaining to the memory task remained the same, in that the two groups did not differ in their memory of factual details from the passages, some interesting patterns emerged in the results pertaining to the interpretation task. First, the four-way interaction involving group, valence, interpretation, and perspective became nonsignificant when the covariates were entered into the analyses. However, the four-way interaction involving group, valence, interpretation, and time remained significant when the results were analyzed using the covariates. These results suggest the possibility that general distress may be more associated with interpretation biases that emerge as a function of perspective, whereas specific symptoms of social anxiety may be related to interpretation biases that emerge as a function of time. Although much research to date has focused on the fashion in which socially anxious individuals interpret self and other relevant perspectives (e.g. Amir et al., 1998), these findings suggest that the time at which individuals make their interpretations may be the most important variable in explaining interpretation biases specifically as they relate to social anxiety. Several limitations of the present study must be acknowledged. First, the sample utilized in this study was from a nonclinical population. Although an extensive screening procedure was utilized to ensure that the sample of socially anxious participants adequately represented this domain of interest (e.g. two screening measures, exclusion of participants from analyses if scores regressed to the mean), it is likely that the participants were not experiencing levels of social anxiety of the same magnitude as a clinical population. Even though significant results were found, conclusions about information processing in social phobia must be reserved until this study is replicated with a sample of individuals with this pathology. A second limitation that should be acknowledged concerns the possibility that the memory task may have been too easy and thus, lacked the sensitivity to sufficiently detect between group differences. Both the socially anxious and the nonanxious individuals recalled over two-thirds of the memory items in the immediate recall condition and approximately half in the delayed recall condition. Therefore, it may be that the items included in the memory task were not difficult enough to distinguish the two groups. In future study in this area, researchers should consider task difficulty as a component in assessing for a memory bias (cf. Wenzel & Holt, 2003). A final limitation of this study is that it did not use conditions that have been demonstrated to elicit memory biases in socially anxious individuals, such as global, negative adjectives (cf. Breck & Smith, 1983) or an anxious activation condition (cf. Mansell & Clark, 1999). Although assessing the recall of factual information was a specific design choice to link the memory and interpretation tasks as directly as possible, it may be that factual details are not sufficiently threatening to detect memory differences between socially anxious and nonanxious individuals. It would be useful for future research in this area to replicate this study, using a memory task that assessed for both factual information, as well as more global, negative adjectives in order to determine if the type of information socially anxious individuals are asked to recall effects the detection of a memory bias. It is hoped that future researchers will continue to extend the methodological advances described in this paper. Results from this study demonstrate the utility of instructing participants to rate the likelihood of all possible interpretations, as well as of assessing participants’ interpretations after a delayed time period. In addition, examining memory for and interpretation of the same threatening material might help to clarify the nature of information processing distortions

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in other anxiety disorders. These data have the potential to be useful in mapping the mechanism by which cognitive biases arise and work together to maintain anxious symptomatology.

Acknowledgements The authors wish to thank Courtney Brostrom, Nicholas Finstrom, Jennifer Kupper, Lindsey Olson, and Ruth Salendar for their assistance with data collection, scoring, and entry, as well as Drs F. Richard Ferraro and Thomas Petros for their guidance with the experimental design and analysis. Portions of this paper are presented in Jennifer R. Brendle’s Masters thesis. Portions of this paper were presented at the Annual Association for the 36th Advancement of Behavior Therapy Conference, Reno, NV, the 1st Annual Northern Lights Psychology Conference, Grand Forks, ND, and the 21st Annual Prairie Undergraduate Research Conference, Winnipeg, MB.

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