Physical context regulates the renewal of fear in ... - SAGE Journals

Journal of Experimental Psychopathology JEP Volume 6 (2015), Issue 1, 13-27 ISSN 2043-8087 / DOI:10.5127/jep.040013

Physical context regulates the renewal of fear in indirect pathways: An examination of fear reduction processes using verbal information provision and modelling Carol Newalla, Isabella Jacombb, Jennifer L. Hudsonb, and Suzanne Broerenc a

Institute of Early Childhood, Macquarie University

b

Centre for Emotional Health, Department of Psychology, Macquarie University

c

Erasmus Medical Centre.

Abstract Among adults, classically conditioned fears that have been extinguished can recover through a change of physical context. Recovery of fear via a change of physical context is typically termed ‘renewal’. In this study, we investigated whether adults also exhibit renewal via the verbal threat information pathway. Fifty adult participants (M = 20 years-old; range: 18 to 45 years of age) acquired fear beliefs about a novel and fictitious animal through the provision of threatening information about the animal. Fears were reduced via the verbal provision of positive information and modelling. Participants were randomised to receive fear reduction in either the same context (Context A) or in a different context (Context B) to the context used for fear acquisition (Context A). All participants were then tested back in the context of acquisition. Results showed fears recovered when the context of fear reduction and the context of test were different, indicating physical context regulates the renewal of verbally acquired and reduced fear. The findings are discussed in terms of current theoretical and developmental models for fear extinction and the implications for relapse models of adult anxiety disorders. © Copyright 2015 Textrum Ltd. All rights reserved. Keywords: extinction, fear reduction, verbal learning, renewal, vicarious learning Correspondence to: Carol Newall, Department of Psychology, Macquarie University 2109, Australia. Email: [email protected] Received 12-Nov-2013; received in revised form 16-May-2014; accepted 16-May-2014

Journal of Experimental Psychopathology, Volume 6 (2015), Issue 1, 13-27

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Table of Contents Introduction Method Participants Design Materials Laptop computer. Fear vignette. Touch boxes. Contexts. Measures State and Trait Anxiety Inventory (STAI). Fear beliefs questionnaire (FBQ). Behavioural Avoidance Task (BAT). Procedure Statistical analyses Fear beliefs. Behavioural approach. Results Preliminary data Fear beliefs Training phases Test phase Behavioural approach task Discussion Acknowledgements References

Introduction Fear learning has been the subject of considerable research interest in the last three decades given that it has the potential to explain pathways to anxiety disorders. One form of fear learning, which has been extensively investigated, is classical conditioning (Pavlov, 1928). This pathway involves direct exposure to a situation or stimulus that is paired with an aversive event. For instance, fear of dogs can be acquired if a person encounters a dog (i.e., conditioned stimulus, or CS) that delivers a painful bite (an unconditioned stimulus, or US). On subsequent encounters with this dog (CS), the person will likely experience anticipatory fear. In classical conditioning terminology, the pairing of the CS and US leads to the formation of an association between the two stimuli, and anticipatory fear to the CS is indexed through behaviours (e.g., avoidance), physiological responses (e.g., elevated heart rate), and heightened self-reported fear in human participants. In some individuals, the anticipatory fear experienced following such aversive conditioning in everyday life can be excessive and debilitating, and can manifest in mental health problems, such as anxiety disorders. For instance, a core diagnostic feature of post-traumatic stress disorder (PTSD) is the experience of a conditioning episode (i.e., a traumatic event), which speaks to the importance of direct learning experiences in some anxiety disorders. A major research area in the Pavlovian conditioning literature is the extensive investigation into fear reduction processes, which has led to advances in the treatment of anxiety disorders (Davis & Myers, 2002; Quirk et al., 2010). One of the most effective ways of reducing fear is via extinction. Fear extinction involves the repeated nonreinforced presentations of the CS, which typically leads to a reduction of anticipatory fear to the CS. An intuitively appealing explanation for fear extinction is the notion that non-reinforced CS presentations are the reversal of fear conditioning – that is, the weakening or loss of the association between the CS and US, typically termed ‘unlearning’ (Estes, 1955; Rescorla & Wagner, 1972). However, this account cannot fully explain loss of fear following extinction given that learned fears can ‘recover’ without further CS-US pairings under certain


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circumstances. For instance, the passage of time can lead to the spontaneous recovery of learned fear (Quirk, 2002). Another robust recovery-of-fear phenomenon is called ‘renewal’. Renewal is the recovery of fear following a change in physical context. For instance, if conditioning occurs in Context A and extinction occurs in Context B, conditioned fear recovers if the subject is tested in Context A. This is called ABA renewal, in which each letter denotes the context of conditioning (A), extinction (B), and test (A). Renewal is also observed in AAB or ABC preparations, discounting the possibility that accrued fear to Context A during conditioning solely accounts for fear recovery in the ABA instance (Bouton & Ricker, 1994). The dominant viewpoint based primarily on renewal findings is that extinction involves new learning rather than ‘erasure’: that is, the creation of a safety memory (CS-no US; Bouton, 2002). This safety memory is thought to be constrained by the context in which extinction occurred. Therefore, the safety memory will only be retrieved in the extinction context but in all other contexts, the subject will default to the retrieval of the threat memory (CS-US). Renewal has been observed in rodents (Bouton & Ricker, 1994; Graham & Richardson, 2010; Yap & Richardson, 2007) and humans (Effting & Kindt, 2007; Vervliet, Baeyens, Van den Bergh, & Hermans, 2013), and has been observed in non-clinical as well as clinical settings. For instance, Mystkowski, Craske, and Echiverri (2002) found that spider phobics exhibited renewal when they were tested in a context different to the one used for exposure therapy. In exposure therapy, patients are gradually exposed to their unique fearful situations and/or stimuli (e.g., spiders) as a technique for fear reduction. Therefore, exposure therapy is the clinical application or analogue of laboratory-based fear extinction procedures. Mystkowski et al. (2002) demonstrated that anxiety recovered in a setting (outdoors) that was different to the one used for exposure therapy (clinical room). Thus, beyond its theoretical importance to extinction processes, renewal is also an important model of relapse for successfullytreated anxiety disorders. While loss-of-fear processes have been researched extensively in direct learning preparations, less is known about fear reduction in other, indirect, learning pathways outlined by Rachman (1977, 1991). These pathways are potentially more ecologically valid as they involve a more social and humanistic approach to the acquisition and loss of fear: the verbal provision of information (e.g., from parents about threats, or from media coverage of disasters) and vicarious learning (i.e., modelling of fear). Considerable research suggests that both instances are viable pathways to fear, especially in children (Askew & Field, 2007; Muris & Field, 2010). Studies that have examined the contribution of indirect pathways to fear learning have used both naturalistic retrospective reports as well as experimental procedures. For instance, Ahern, Galea, Resnick, and Vlahov (2004) illustrated that more viewing of television in the 7 days after the terrorist attack on the World Trade Centre (9/11) increased the odds of acquiring PTSD symptomology in adult New York residents. The findings from naturalistic studies illustrating the role of indirect learning in fear acquisition are further supported by the results of experimental studies with children. For instance, several studies have now shown that when children are given threatening verbal information about an unfamiliar animal, they will develop increased fear beliefs about that animal (Muris & Field, 2010). The acquired fear is also indexed by children’s longer time to approach the animal’s cage (e.g., Muris et al., 2009). These laboratory-based studies illustrate a causal pathway between the provision of threatening verbal information and the development of fear in children. Interestingly, a few recent studies have now shown that fear can also be reduced in children through the provision of positive verbal information about the animal or modelling of approach behaviours towards the animal by the experimenter (Kelly, Barker, Field, Wilson, & Reynolds, 2010; Muris, Huijding, Mayer, van As, & van Alem, 2011). Some researchers within this field have used the term ‘unlearning’ to describe the loss of fear observed using this paradigm (Kelly et al., 2010), although the specific processes of fear reduction in this paradigm have not been researched in children or adults. As noted earlier, the field of classical conditioning makes a distinction between ‘unlearning’ (erasure of the fear memory) and new learning or ‘masking’ (the development of a new safety memory (i.e., CS-noUS; Bouton, 2002; Quirk et al., 2010). To date, it is not clear whether indirect pathways of fear reduction involve masking/new learning or erasure/unlearning. A notable exception is a study by Soeter and Kindt (2012). In that study, an experimenter told adult participants that a mild shock would be delivered through attached electrodes on their fingers following a CS presentation (visual stimulus) on a computer screen. This verbal instruction led to an increase of fear to the visual stimulus (CS) in participants. The researchers then employed a classical conditioning procedure for fear extinction: repeated, non-reinforced presentations of the CS, which led to a decrease of fear.


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Soeter and Kindt (2012) found that fear to the CS renewed when participants were presented with the CS on a computer screen background context that was different to the one used for extinction. That is, renewal occurred when the fear was verbally acquired but extinguished via classical conditioning. Interestingly, there has not been any study to date that has examined whether fear reduction via the provision of positive verbal information and modelling also engages new learning processes that are vulnerable to fear recovery, such as renewal. It is worth noting that the provision of positive information about a feared situation, or modelling of approach behaviours by the experimenter in indirect learning paradigms does not map directly onto Pavlovian fear extinction procedures even though both procedures reduce fear. One possible interpretation is that the animal is the CS, and the negative information provided during fear acquisition functions as the US. During the provision of positive information or modelling of approach behaviours, the participant may be experiencing something similar to ‘extinction’ in the direct fear learning approach. Specifically, the participant is being exposed to the animal (CS) without the associated negative information (US). However, a closer analogue in the Pavlovian conditioning literature to fear reduction techniques used in indirect learning paradigms is a procedure called counterconditioning. Counter-conditioning reduces learned fear by pairing a feared CS (previously paired with shock for instance) with a motivationally antagonistic US, such as a food reward for a rat (Peck & Bouton, 1990) or the sound of a baby’s laugh for human participants (instead of a startling white noise; Raes & De Raedt, 2012). Thus in indirect learning paradigms, the provision of positive information and observing a positive outcome of another person approaching the feared stimulus is more akin to counter-conditioning procedures. That is, indirect learning procedure involves the provision of motivationally antagonistic information about the novel animal during fear reduction (Dunne & Askew, 2013). Interestingly, like extinction, recovery of fear has also been observed using counter-conditioning procedures. That is, there is some evidence to suggest that counter-conditioning does not erase the original CS-US association and may also involve the new learning of a safety memory, which is similarly gated by its context like extinction (Bouton & Peck, 1992; Brooks, Hale, Nelson, & Bouton, 1995). Therefore, there is some evidence to suggest that indirect learning paradigms, that may be analogues of counter-conditioning, also involves ‘new learning’ during fear reduction. It is possible then, that indirect learning paradigms for fear reduction are also vulnerable to the recovery of fear when the participant is moved out of the context for fear reduction (i.e., renewal). It is worth noting however, that there is considerably less research available on counter-conditioning than extinction, and whether counter-conditioning performs like extinction (Raes & De Raedt, 2012) or whether it in fact thwarts renewal is a subject of ongoing investigation (Thomas, Cutler, & Novak, 2012). The current study examines whether adults exhibit renewal when fear is reduced through the provision of verbal information and modelling of approach behaviours. We commenced our research using adults given that emerging rodent studies suggest that the renewal of classically conditioned fear may be absent early in life (Callaghan & Richardson, 2011; Yap & Richardson, 2007) and therefore, renewal of fear may not occur in children. Using Muris and Field’s (2010) paradigm, adult participants were provided with threatening written information about an unfamiliar animal (fear acquisition phase). Fear reduction techniques using positive verbal information and modelling were then delivered. Participants were randomly assigned to experience fear reduction in either the same context as fear acquisition (Context A) or a new context (Context B). All participants were tested back in Context A. Therefore, the experimental design involved two groups: Group AAA and Group ABA (each letter denotes the context of fear acquisition, fear reduction, and test). If fear reduction via indirect learning procedures involves new learning (Bouton, 2002; Bouton & Ricker, 1994; Peck & Bouton, 1990), then we would expect participants to only retrieve safety memories in the context of fear reduction, and exhibit renewal when tested outside the context of fear reduction. That is, at test, participants in Group ABA should report and exhibit more fear than participants in Group AAA. However, if fear reduction involves ‘unlearning’ or erasure of the fear memory, we should observe low levels of fear across both groups.

Method Participants Fifty participants (10 men and 40 women) were recruited into this study. All of the participants were students from Macquarie University who chose to either receive partial course credit or to be entered into a draw to win a $50 gift


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voucher in return for their participation. The current study was approved by the Macquarie University Ethics Committee for Human Research. Participants were randomly assigned to one of two groups with equal sample sizes (n = 25). Demographic information for each group can be found in Table 1. Table 1: Participant characteristics and STAI scores Group AAA Measure Age Gender (% female)

Group ABA

M

SD

M

SD

19.6

3.1

22.4

6.8

80

80

STAI-State

35.0

9.3

37.0

11.0

STAI-Trait

42.4

7.6

44.0

10.5

Note. STAI = State Trait Anxiety Inventory. AAA = fear acquisition in Context A, fear reduction in Context A, and test in Context A; ABA = fear acquisition in Context A, fear reduction in Context B, and test in Context A. All values represent raw, nonstandardised scores

Design The study was a two-group experimental design, which investigated whether contextual change between the ‘extinction’ and test phases resulted in the recovery of fear, as indexed by the fear beliefs questionnaire and behavioural approach task (see Materials and Procedure for further description). Participants were therefore randomly assigned to experience the extinction and test phase in the same context (Group AAA, n = 25) or in different contexts (Group ABA, n = 25). Fear acquisition involved verbally transmitted threat information about a fictitious animal and fear reduction involved the provision of positive information about the animal as well as modelling. Self-reported fear beliefs were assessed at the end of each phase: baseline, post-fear acquisition, postfear reduction, and test (i.e., post-contextual manipulation). The latency to approach a touch box, which participants were led to believe housed the fictitious animal, was measured once at test. We did not include a postfear acquisition and post-fear reduction measure of this behavioural approach task as a baseline measure prior to test because we wanted to avoid further ‘extinction’ for participants who might choose to approach the box prior to our experimental manipulation. Additional extinction would provide another learning experience for some participants, which may therefore confound our test results.

Materials Laptop computer. A Toshiba computer was used to administer all self-report measures. We used an online, secured, and licensed software package called Survey Gizmo (www.surveygizmo) to host our questionnaires.

Fear vignette. The vignette was modelled on Field and colleagues’ vignettes used in previous studies for children (Muris & Field, 2010) with several modifications to make it suitable for an Australian adult sample. The vignette provided threatening information about the novel animal (see Supplementary Materials for the entire vignette). Participants were instructed that their task was to guess the type of animal described in the vignette. Participants were asked at each phase of the experiment to guess the type of animal housed in the box 1.

1

Chi-square analyses suggest that there were no significant differences between groups at each phase (ps < .05). There was considerable variability at baseline, with the most common guesses for a bird or a snake. After reading the vignettes, the most common animal mentioned was the possum, a common Australian mammal, and this trend was maintained in subsequent phases.


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Touch boxes. A wooden box was used to deceive participants into believing an animal was housed inside it. This wooden box was a variant of the touch boxes successfully used by Field and colleagues in other studies (e.g. Field & Lawson, 2003). The box contained pine shavings, a piece of faux fur, and a small iRiver mp3 player that played guinea pig noises and rustling sounds. The front of the box had 1 medium sized hole (diameter = 90 mm) which was lined with black fabric to prevent participants from seeing the inside of the box.

Contexts. Two contexts were established for our experimental manipulation. The two rooms differed in terms of size, luminosity, temperature, and general ‘atmosphere’. Specifically, we modelled the style of the rooms on Schiller and colleagues’ (2008) experimental design, which examined classically conditioned fear whilst controlling for physical context. Like Schiller et al. (2008), one of our contexts was made more visually cosy and inviting, and the other context was significantly more clinical from an aesthetic point of view. In the ‘cosy’ context, the room was smaller, with softer lighting, and a perfumed air was provided by a commercial brand air freshener. It also featured posters on the wall, a table with a chequered tablecloth, a vase with flowers, and a lamp. The temperature in this room was kept constant at 28°C. The second room was a larger space used to cater for group therapy by a psychology clinic. The temperature was kept constant at 19°C. This room featured standard office furniture, with a table and 2 chairs. The walls were bare and the room was lit via overhead fluorescent lighting. The two rooms were located on the same floor, a few doors away from each other and across a small corridor. Each room was counterbalanced to serve as Context A and B.

Measures State and Trait Anxiety Inventory (STAI). The STAI (Spielberger, 1983) assesses state and trait anxiety. Each item is evaluated on a 4-point Likert scale (1 = Almost Never/Not at all to 4 = Almost always/Very much so). The psychometrics of this scale are well-established (Spielberger, 1983). The internal consistency of the scale in the current study was excellent for the trait scale (α = .90) and good for the state scale (α = .84).

Fear beliefs questionnaire (FBQ). The FBQ (Field & Lawson, 2003) assesses participants’ fear beliefs about the novel animal. The FBQ consists of 8 questions about the novel animal with responses made on a 5-point Likert scale (0 = No, not at all to 4 = Yes, definitely). The mean score was used as the index of fear. The FBQ has shown moderate to good internal consistency (e.g. Field, 2006b). In the current study, the internal consistency coefficients were in line with those found in previous studies, and ranged from α = .82 -.87 across all phases of the experiment.

Behavioural Avoidance Task (BAT). A touch box was used as a BAT in this study. The touch box was situated 3m from the participants’ start point (i.e., a chair behind a desk with a computer) in both contexts. For the task, participants were told that the touch box contained the animal and they were instructed to place their hand in the hole to pat the animal to help them decide what type of animal it is. Latency was measured as commencing when the experimenter finished delivering her instructions to the time participants put their hand in the cage up to their wrist. Participants who refused to put their hand in the box were recorded as having taken 120 seconds to finish the task, the maximum time allocated for participants to complete this task. To eliminate potential experimenter bias, the BAT was video recorded and a


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second investigator blind to experimental conditions also timed all the participants for approach latencies. An excellent level of inter-rater agreement was found, with a single measure intra-class coefficient of r = 1.00.

Procedure After providing informed consent, participants were advised that they would be given information about the novel animal and that their task was to guess the type of animal housed in a box nearby. Participants were also told that at the end of the study they would be invited to pat the animal. The experimenter provided information about her expertise in animal behaviour to augment her authority during this initial introductory period. This modification was included because our pilot study (N = 30) revealed that adult participants did not show a decline in fear following positive information and modelling by the experimenter because they did not perceive the experimenter as having sufficient ‘expertise’ to contradict the vignette. Participants completed the STAI and FBQ, and guessed the type of animal housed in the box before they read the vignette (baseline measure). After reading the vignette, the participants again filled out the FBQ and made a second guess on the type of animal housed in the box (post-fear acquisition measure). All participants were then instructed to return to the waiting room, on the pretext of booking issues with the current room (Context A). They waited there for approximately two minutes before the experimenter returned to collect them for the next phase of the study. Participants assigned to Group ABA (n = 25) were informed that a room change was necessary, and that the second part of the experiment would be held in another room because of booking conflicts. The experimenter explicitly told the participants in Group ABA that the animal from Context A had been moved into the new room (Context B). Participants in Group AAA (n = 25) returned to the same room, having been informed that the booking issues had been resolved. Therefore, the fear reduction phase for participants occurred in either the same room (Context A) or a different room (Context B). During the fear reduction phase, the experimenter provided more information about the animal, on the pretext of facilitating with the task of identifying the animal (“The animal is generally nocturnal, but it has been known to be awake for short periods during the day, especially during mating periods”). The experimenter then casually approached the cage to feed the animal, and provided the following information: “This animal is really friendly. He’s so cute! I know it says he bites, but he has never bitten me”. The experimenter then placed her hand in the box to feed and pat the animal to model nonanxious behaviours towards the animal. Participants then completed the FBQ again (post-fear reduction). Following this, the experimenter again led all participants back into the waiting room with the excuse that there were further room booking issues. At test phase, all participants were led back into Context A for the test phase. Therefore, participants in Group AAA and Group ABA received identical procedures with the exception that extinction took place in a different room for Group ABA. During the return to Context A for Group ABA, the experimenter explicitly noted to the participants that the animal had been moved back to Context A. Participants then completed the FBQ again and the BAT was administered as the final task (test phase). Following the experiment, all participants were debriefed about the experiment and its deception. Prior to debrief, we asked participants about the aims of the study. None of the participants reported that they knew about the main goals of the study, or the deception involved in the study. During debrief, they were informed there was no real animal in the box, that the room booking conflict was bogus, and that the experimenter was not an animal expert. All participants were given the opportunity to re-consent following this debrief. No participants withdrew their consent at this stage.

Statistical analyses Fear beliefs. Fear beliefs were analysed as change across time (i.e., phases) between groups. When sphericity was not met, the Greenhouse-Geisser modification to repeated measures was used (Field, 2009). To evaluate the training phase (baseline, post-fear acquisition and post-fear reduction), we used an overall between-within analysis of variance (ANOVA) to examine Time and Group (ABA vs. AAA) effects. The Time is a repeated measure, and Group is a between-subject factor. We conducted follow-up tests and evaluated fear acquisition. For this, we used a between-


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within ANOVA to examine Time (baseline to post-fear acquisition) × Group (ABA vs. AAA) effects. To evaluate fear reduction, we used the same statistical procedure with the exception that the time points changed: Time (post-fear acquisition to post-fear reduction) × Group (ABA vs. AAA) effects were analysed. At test phase, we assessed whether Group ABA exhibited more fear than Group AAA with the change of context from post-fear reduction to test. Therefore, we again conducted a Time (post-fear reduction to test) × Group (ABA vs. AAA) analysis, with the prediction that there would be a significant interaction (i.e., that increases in fear across time depended on group).

Behavioural approach. The distribution of approach latencies was moderately non-normal and remained non-normal even after transformations were made. Therefore, we used a non-parametric statistical test (i.e., the Mann-Whitney U test) to examine group differences for the BAT.

Results Preliminary data Preliminary results are shown in Table 1. Although there were more women than men participating in the study, the proportion of sexes was evenly distributed across the two conditions, χ2(1, N = 50) = 0, p > .05. Results also revealed that there were no group differences in age, trait, or state anxiety at baseline, ps > .05.


Test

Training 3.5

Mean Fear Beliefs

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AAA ABA

3.0

2.5

A

A

B

A

A

A

tio n du c re ar

Po st -fe

Po st -fe

ar

ac

B

as

qu is

el

iti

on

in e

2.0

Time

Groups

Figure 1. Mean fear beliefs score across training and at test for participants in Groups ABA and AAA.

Fear beliefs Training phases Figure 1 summarises the mean FBQ ratings. An overall mixed ANOVA of Time (baseline, post-fear acquisition, and post-fear reduction) × Group revealed a significant main effect of Time F(2, 47) = 25.47, p < .001, ηp2 = .52. There was no significant main effect of Group or of Time × Group interaction (ps > .05). The sections below outline the follow-up analyses to examine acquisition and extinction effects.

Fear acquisition. As expected, an ANOVA revealed a significant main effect of Time, F(1, 48) = 13.26, p < .01, ηp2 = .22, indicating an increase in fear beliefs from baseline to post-acquisition. There were no other significant effects (all ps ≥ .13), indicating that both groups reported similar rates of fear acquisition. Furthermore, there were no group differences in fear beliefs at baseline, t(48) = .73, p > .05, r = .10, or post-fear acquisition, t(48) = 1.75, p > .05, r = .25 (a small to medium effect size).

Fear reduction. As can be seen in Figure 1, FBQ ratings for both group declined from post-acquisition to post-fear reduction. This was confirmed in our analysis, indicating a significant main effect of Time, F(1, 48) = 51.90, p < .001, ηp2 = .52. There were no other significant effects (all ps ≥ .11). Therefore, groups reported similar rates of fear reduction. Furthermore, there were no group differences at post-fear reduction, t(48) = 1.32, p > .05, r = .19.


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Test phase As illustrated in Figure 1, the change in fear beliefs across tie depended on group assignment. Specifically, there was no significant main effect of Time, F(1, 48) = .40, p > .05, ηp2 = .01, or Group, F(1, 48) = 3.53, p > .05, ηp2 = .07. However, there was a significant Time × Group interaction, F(1, 48) = 4.05, p < .05, ηp2 = .08. Follow-up analyses revealed that the two groups were not different at post-extinction, t(48) = 1.32, p > .05, r = .19, but that Group ABA reported significantly more fear beliefs about the animal than Group AAA at test, t(48) = 2.31, p = .025, with a medium-sized effect of r = .32.

Behavioural approach task For the BAT, Group ABA (Mdn = 30.64) took significantly longer to approach the touch box than Group AAA (Mdn = 20.36) at test, U = 441.00, z = 2.52, p < .05, r = .36.

Discussion This study examined whether a change of context for fear reduction led to the recovery of fear via the verbal information pathway in adult participants. We demonstrated that like children (Field & Lawson, 2003; Kelly et al., 2010), adults reported greater fear beliefs about an unknown animal when given threatening information about that animal. Moreover, like children in previous studies (Kelly et al., 2010; Muris & Field, 2010), the provision of positive information and modelling of approach behaviours by the experimenter also reduced fear in adults. Given that the paradigm was initially designed to examine fear acquisition in children, our results indicate that the vignettes as well as the deception (i.e., that there is an animal in the box) are believable to adult participants too, and may be an experimental procedure that can be used in the future to examine other causal variables of fear acquisition and reduction in adults. More importantly, we have documented the recovery of fear (renewal) in our current study, a well-established finding within Pavlovian conditioning research. Specifically, our results revealed that participants who experienced a context switch during the study (ABA) reported more fear and were slower to approach the animal’s cage at the test phase compared to participants who experienced the same context throughout the study (AAA). To our knowledge, this is the first study to document renewal using verbal information and modelling as methods for fear reduction. The renewal of fear in our study is consistent with the Pavlovian conditioning literature. Specifically, both adult rats (e.g., Bouton, 2002; Maren, 2013) and humans (e.g., Neumann & Kitlertsirivatana, 2010) exhibit renewal when the context of fear reduction is different to the one used for the test phase. Notably, classically conditioned fear (i.e., the direct fear learning pathway) is typically reduced via the repeated non-reinforced presentation of a feared cue, such as a tone or light that was previously paired with an aversive outcome (e.g., tactile shock for a rat). The most robust effects of renewal are found following this form of fear reduction (i.e., extinction). Interestingly, while our form of ‘fear reduction’ in this indirect pathway procedure is consistent with the renewal phenomenon observed in classically ‘extinguished’ fears, our method of positive information provision and modelling of approach behaviour more closely parallels counter-conditioning in the Pavlovian conditioning literature. Our results are consistent with several counter-conditioning studies (however, see also Thomas et al., 2012). That is, the provision of positive experiences such as safety information about the animal (i.e., “he’s so cute …he’s never bitten me!”) and the observation of another person’s willingness to approach the animal also reduces fear. Moreover, when tested in a context that was different to the one used for fear reduction/counter-conditioning, the learned fear was renewed (Bouton & Peck, 1992; Brooks et al., 1995). One advantage of studies examining indirect pathways of fear reduction is that this method may be a more ecological valid model for tracking how most fear diminishes in real life. One would expect that the most common form of fear reduction in everyday life is through the provision of safety information and observing other people modelling approach behaviours. For instance, an individual nervous about social gatherings will likely encounter people who will encourage that socially anxious individual to attend a party by providing him/her with positive information about that party. A parent of a young child afraid of dogs will likely approach and pat a dog in front of their child (i.e., modelling) thus reassuring the child that the situation is safe (i.e., fear reduction) before the child attempts to pat the dog. This form of fear reduction also occurs within a clinical context. Exposure to an anxiety-


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provoking situation is typically conducted in a gradual manner, with less fearful situations attempted prior to more fear provoking situations – usually called exposure ‘steps’ or hierarchy. Early exposure steps might involve the clinician modelling approach behaviours that are uniquely anxiety-provoking for the individual (Bennett-Levy et al., 2004). For example, a socially phobic individual may have a severe fear of asking for help at shops or returning an item. Typically, early exposure steps may involve observing the therapist or a friend return an item at a shop and for the client to note that the sales assistant does not become angry or upset at this exchange. This ‘vicarious learning’ exposure step (i.e., indirect learning) can greatly reduce the clients’ anxiety and increase motivation to engage in the more difficult step of returning the item to a shop (i.e., direct learning). Given that modelling/vicarious learning and the provision of positive information is often used prior to more direct experiences of fear reduction, it is surprising that there is limited research into processes of ‘counter-conditioning’ via these indirect pathways (Kelly et al., 2010; Muris et al., 2011; Ollendick, Lewis, Cowart, & Davis, 2012). Therefore, considerably more research is needed to examine whether counter-conditioning involves erasure or new learning given its ecological applicability to loss of fear in humans. Our current results show that fear reduced via positive information and modelling in adults can be renewed, which has clinical implications. That is, it appears that fears acquired through verbal information and reduced via the provision of positive information and modelling are relapse-prone in adults. Future studies are needed to verify whether renewal of indirectly acquired and reduced fear is also observed in a clinical sample. An important point to consider is the relative contribution of positive information provision and modelling of approach behaviours to fear reduction and whether both techniques are prone to renewal. We used both techniques in conjunction to maximise the probability of fear reduction in our study and therefore, cannot disentangle the relative contribution of each technique to fear reduction and renewal. However, a future avenue for research is to study whether one form of fear reduction is more vulnerable to fear renewal than the other. Studies to date have found positive information to be more effective in reducing fear for children than modelling of approach behaviours (Kelly et al., 2010) and imagery exposure (Muris et al., 2011). It remains to be seen whether positive information provision might also be relatively more robust against renewal than other fear reduction techniques in adults. Although our results seem to show that new learning is involved in fear reduction, consistent with Bouton’s model for fear extinction/reduction, it is worth noting that our results are not conclusive yet. This is because we only set out to examine the most robust renewal preparation: ABA renewal, within the verbal fear learning paradigm. Within Bouton’s model (2002), renewal should also occur with AAB and ABC preparations given that the critical shift is between the context of extinction and test. Although AAB and ABC renewal has been documented in rats, it is typically not as robust as ABA renewal (Bouton & Ricker, 1994; Harris, Jones, Bailey, & Westbrook, 2000) and sometimes, not observed at all (Bouton & King, 1983; Yap & Richardson, 2007). There is considerably less research within the human literature on these other forms of renewal (Neumann & Kitlertsirivatana, 2010). One alternative account of our findings, given that we did not include AAB or ABC groups, is that recovery of fear was not due to new learning (i.e., the creation of ‘animal is safe’ memories) during fear reduction but could be accounted for by other factors. For instance, fear reduction in Context B for Group ABA may have prevented extinction/counter-conditioning of Context A. A well-known phenomenon is that one can acquire fear to specific discrete cues (e.g., the animal) and to the context in which these cues occur (e.g., the Context A room; Vervliet et al., 2013). Unlike Group AAA, Group ABA would not have extinguished/counter-conditioned fear to Context A. Therefore, the comparatively greater fear response observed in Group ABA compared to Group AAA at the test phase may have been due to elevated fear of Context A for Group ABA. Therefore, future studies may need to explore this alternative account with the inclusion of AAB and ABC groups. To date, no study has examined whether children also exhibit renewal of fear, like adults. This is an important issue to explore in future studies given that most anxiety disorders have their origin in childhood (Cartwright-Hatton, McNicol, & Doubleday, 2006). Although there are several studies that have documented fear acquisition and extinction in children using classical conditioning procedures to examine anxiety disorders pathways (Liberman, Lipp, Spence, & March, 2006; Waters, Henry, & Neumann, 2009), none have examined whether fear extinction involves erasure or new learning via recovery-of-fear preparations such as renewal. Within the indirect fear learning literature, no study has yet examined recovery of fear following fear reduction in children. The indirect fear learning


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field is ideally placed to examine this very topic given that the paradigm used was specifically designed for children, and works effectively within the ethical constraints of investigating learned fear in children (Muris & Field, 2010). We did not first set out to examine children because we were aware of the growing pre-clinical literature indicating that recovery of fear is absent early in life in rodent models (Gogolla, Caroni, Luthi, & Herry, 2009; Kim & Richardson, 2008, 2010; Langton, Kim, Nicholas, & Richardson, 2007; Yap & Richardson, 2007). That is, to date, there is no evidence of fear recovery following extinction in standard-reared infant rats, which includes the absence of renewal (Yap & Richardson, 2007). Therefore, evidence suggests that fear extinction early in life may involve the ‘erasure’ or ‘unlearning’ of fear memories (Langton et al., 2007). Thus, had we set out to examine renewal in children, we may have encountered null effects and would not be able to distinguish a methodological problem from the possibility that children may use erasure for fear reduction. Our study has completed a critical first step to investigating this developmental question: we have provided evidence that renewal can occur in adults using verbally acquired and reduced fears. This establishes an ideal foundation for future developmental studies to explore whether children also exhibit renewal via indirect fear pathways, or whether this fear recovery phenomenon is absent, thus supporting the possibility that children, like infant rats, may also engage erasure for fear reduction. Several limitations should be noted for our study. An important constraint in our design is the absence of control groups for fear acquisition (i.e., No Fear Acquisition groups) and fear reduction (i.e., No Fear Reduction groups). The absence of these groups precludes us from ruling out potential confounds for the effects detected in our study. For instance, the greater fear found in Group ABA compared to Group AAA at test may have been due to general arousal caused by contextual changes rather than recovery of learned fear acquired via threatening information provision. The inclusion of No-Fear Acquisition groups would have ruled out this possibility. Furthermore, it is not clear whether ABA fear recovery is due to fear reduction processes rather than forgetting processes because we did not include No-Fear Reduction groups. As this was the first preliminary exploration of the topic, we chose to focus exclusively on the two critical groups: ABA vs. AAA. However, it is essential that future studies include these important control groups to ensure that training and test effects are due to previous indirect learning experiences and counter-conditioning, and not competing processes such as general arousal, forgetting, or regression to the mean. Furthermore, future studies should also consider including a within-subject control animal (no threatening information) to ensure that any fluctuations in fear beliefs across time is due to indirect learning, and not due to general differences in fear to animals between groups. This study modified a child indirect learning task for adults. Therefore, there is a possibility that the deception may not have been believable to adults. Moreover, had adults correctly identified the goal of this study, there is also the possibility that demand characteristics contributed to the effects found in the study. However, these possibilities seem unlikely in light of a few important factors. First, although we did not ask the participants directly about the procedure and its ‘believability’, there were no instances of participants declaring at debrief that the animal was not real, nor did any participants correctly guess the actual goals of the study (i.e., that the room changes were bogus and was part of the experimental manipulation). Second, as participants were not aware that they would be timed for BAT, it would seem rather unlikely that group differences were due to demand characteristics. Participants were told that they should pat the animal for the BAT in order to help them identify the type of animal housed in the cage. The experimenter did not use a timer in the presence of the participant, and instead, recorded latency to approach based on the video recording. Therefore, it would seem highly unlikely that participants modified the timing of their approach behaviours to meet our study predictions. We also acknowledge the possibility that participants in Group ABA may have assumed that the animal in Context B was different to the one used for Context A. This may have accounted for greater fear in Group ABA compared to Group AAA at test, if Group ABA participants assumed that the safety messages and approach behaviours were applicable to the animal in Context B but not to a different animal in Context A. However, this explanation seems unlikely for a number of reasons. If participants believed that a different animal was housed in Context B, then we would expect greater loss of fear following positive information and modelling (post-fear extinction phase) with that ‘new’ animal in Context B for Group ABA compared to Group AAA. However, differential rates of fear reduction between groups were not observed. Moreover, we included the deception of the room booking conflicts as an excuse for shifting rooms so that we could make explicit to the Group ABA participants that we were moving all the equipment, including the animal, from Context A to Context B for that phase of the experiment. We used the same


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excuse, using the same explicit statement of moving the equipment and animal, for the shift from Context B back to Context A for test (Group ABA). There were no instances of participants mentioning that they had thought that the animal was different in each context. Therefore, although it is possible that participants’ beliefs about different animals in each context could account for our renewal effect, we deem this unlikely. A final limitation is the procedure for the BAT. First, we chose to only administer the BAT once at test. Therefore, there is the unlikely chance that group differences detected at test may have been due to pre-existing differences prior to experimental manipulation. While other researchers have successfully administered the BAT twice to detect time by group interactions (e.g., Kelly et al., 2010), we chose to exclude a baseline BAT because we were concerned that two administrations of the BAT (post-fear reduction to test) would lead to an important confound: this would have led to additional fear extinction, and therefore additional learning experiences, for participants who choose to put their hands in the touch boxes for the first BAT (post-fear reduction) prior to test, and possibly discovering that there was no animal in the touch box. An additional limitation of the BAT is that we were not able to eliminate all possibilities of experimenter bias during this task. This is because the experimenter was not blind to participant group assignment during the BAT. Thus the experimenter may have delivered instructions for the BAT in a subtle and non-verbal manner that either encouraged or discouraged the participant to approach the animal based on the participant’s group assignment. Future studies may need to consider the use of a second experimenter blind to experimental conditions to deliver the BAT. These limitations notwithstanding, our study provides valuable information about loss of fear processes in adults via the indirect fear pathways (verbal learning and modelling). Our results suggest that like classical fear conditioning, fear acquired through threatening verbal information, and diminished through the provision of positive information and modelling, are also vulnerable to fear recovery. This study has shown that a change of physical context used for fear reduction can lead to fear renewal in adult participants, as indexed by both self-report and behavioural measures. These findings have clinical implications given that fear acquisition is one potentially important pathway to anxiety disorders. An understanding of how to dismantle and reduce fears effectively, especially through ecologically valid and often-used techniques such as positive information provision and modelling can greatly inform the prevention and intervention of anxiety disorders.

Acknowledgements We thank Shirley Reynolds for her advice on methodology.

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