Let's play pretend: Towards effective modelling in experimental psycho(patho)logy.

BACKGROUND AND OBJECTIVES: Models are omnipresent in science. We introduce a novel framework to achieve more effective modelling practices in general psychology and experimental psychopathology. METHOD: We analyze three types of models that are common in psychology: laboratory models, computational models, and cognitive models. We then evaluate two common ways to assess the translational value of models (phenomenological similarity and deep similarity) as well as an arguably underappreciated way (functional similarity). Functional similarity is based on an assessment of whether variables (e.g., the administration of a pharmacological substance) have a similar effect (a) in the model (e.g., in a fear conditioning procedure) and (b) on the real-life target phenomenon (e.g., on real-life anxiety complaints). CONCLUSIONS: We argue that the assessment of functional similarity is a powerful tool to assess the translational value of models in the field of experimental psychopathology and beyond.

The first steps in facing your fears: The acceptability of virtual reality and in vivo exposure treatment for specific fears.

Phobic individuals are often reluctant to engage in exposure in vivo (IVE). We examined whether providing exposure in virtual reality (VRE) can increase the acceptability. In Study 1, we provided 186 fearful participants with (hypothetical) VRE and IVE treatment offers and examined their willingness to engage in treatment, estimated success, negative beliefs, acceptance/refusal and their preference. Almost 70 % preferred VRE over IVE and acceptance rates were higher for the VRE offer (58 %) than for IVE (35 %). Although participants held fewer negative beliefs about VRE, they did rate IVE as slightly more successful. In Study 2, we examined whether VRE can serve as a stepping stone to IVE in a sample of 102 spider fearful individuals. Willingness to engage, estimated success and negative beliefs about IVE were assessed before and after VRE. After VRE, participants rated IVE as more successful, but were not more willing to engage in IVE, nor were they more inclined to accept an IVE offer. No decreases in negative beliefs were observed. In conclusion, VRE is deemed more acceptable than IVE and could lower refusal rates, hereby resulting in more phobic individuals receiving treatment. Future research should shed light on underlying motivations and associations.

Understanding clinical fear and anxiety through the lens of human fear conditioning.

Fear is an adaptive emotion that mobilizes defensive resources upon confrontation with danger. However, fear becomes maladaptive and can give rise to the development of clinical anxiety when it exceeds the degree of threat, generalizes broadly across stimuli and contexts, persists after the danger is gone or promotes excessive avoidance behaviour. Pavlovian fear conditioning has been the prime research instrument that has led to substantial progress in understanding the multi-faceted psychological and neurobiological mechanisms of fear in past decades. In this Perspective, we suggest that fruitful use of Pavlovian fear conditioning as a laboratory model of clinical anxiety requires moving beyond the study of fear acquisition to associated fear conditioning phenomena: fear extinction, generalization of conditioned fear and fearful avoidance. Understanding individual differences in each of these phenomena, not only in isolation but also in how they interact, will further strengthen the external validity of the fear conditioning model as a tool with which to study maladaptive fear as it manifests in clinical anxiety.

In safe hands: Attachment figures' safety properties and the link with attachment style.

According to the Learning Theory of Attachment, naturalistic learning experiences about others' responsiveness during distress are an underlying mechanism in the development of attachment. Previous studies have demonstrated attachment figures' unique safety-inducing effects in highly controlled conditioning procedures. Yet, neither have studies examined the presumed influence of safety learning on state attachment, nor have they examined how attachment figures' safety-inducing effects relate to attachment styles. To address these gaps, a differential fear conditioning paradigm was used in which pictures of participants' attachment figure and two control stimuli served as safety cues (CS-). US-expectancy and distress ratings were measured as indicators of fear responding. Results indicate that attachment figures evoked enhanced safety responding compared to control safety cues at the start of acquisition, which was maintained throughout acquisition and when presented together with a danger cue. Attachment figures' safety-inducing effects were reduced in individuals with higher attachment avoidance, although attachment style did not affect the rate of new safety learning. Finally, safe experiences with the attachment figure in the fear conditioning procedure resulted in diminished anxious state attachment. Adding to previous work, these findings underscore the importance of learning processes for attachment development and attachment figures' provision of safety.

Predicting clinical outcomes via human fear conditioning: A narrative review.

A common assumption in human fear conditioning research is that findings are informative for the etiology and treatment of clinical anxiety. One way to empirically evaluate the external validity of fear conditioning is by prospective studies. We review available prospective research investigating whether individual performance in fear conditioning predicts individual differences in anxiety levels and exposure-based treatment outcome. We focus on fear extinction, generalization, acquisition, and avoidance. Results suggest that reduced extinction and broader generalization predict higher anxiety levels. Results with respect to the predictive value of acquisition for anxiety levels are mixed. With regard to predicting exposure-based treatment outcome, some studies do find an association with extinction whereas others do not. The majority of studies does not find an association with acquisition. Evidence on extinction recall is limited and not consistent. The interpretation of these results requires caution. The number of available studies is limited. It is possible that not all work, in particular studies with only null effects, has found its way to publication. Future research on this topic will benefit from large sample sizes, preregistered hypotheses, full transparency about the conducted analyses and the publication of high-quality studies with null effects.

Validation of the Impact of Event Scale With Modifications for COVID-19 (IES-COVID19).

Viral outbreaks can be experienced as disruptive and can be associated with trauma-related stress symptoms. In the current study, we adjusted the Dutch version of the Impact of Event Scale (IES) to assess traumatic stress symptoms related to the impact of the COVID-19 outbreak. The psychometric properties of this Impact of Event Scale with modifications for COVID-19 (IES-COVID19) were investigated by administering the IES-COVID19 to 380 university students who participated during the early stage of the COVID-19 outbreak, upon invitation via e-mail. Using confirmatory factor analysis, the factor structure of the IES-COVID19 was found to be similar to the original IES, indicating two latent factors: intrusion and avoidance, χ2 (85) = 147.51, CFI = .92, TLI = .90, RMSEA = .044, SRMR = .049. Cronbach's alpha showed acceptable internal consistency of the total IES-COVID19, α = .75. Pearson's correlations of the IES-COVID19 over time were also sufficient, demonstrating adequate test-retest reliability, r = .62. Significant correlations (ranging between .15 and .50) between the IES-COVID19 and symptoms of depression, anxiety, stress, stress-related rumination, as well as negative social interactions, demonstrate adequate convergent validity. Overall, the IES-COVID19 shows to be a valid and reliable measure that can be utilized to investigate trauma-related stress symptoms of intrusion and avoidance related to the short- and long-term impact of the COVID-19 outbreak.

Modeling Hierarchical Versus Random Exposure Schedules in Pavlovian Fear Extinction: No Evidence for Differential Fear Outcomes.

In exposure therapy, the client can either be confronted with the fear-eliciting situations in a hierarchical way or in a random way. In the current study we developed a procedure to investigate the effects of hierarchical versus random exposure on long-term fear responding in the laboratory. Using a fear conditioning procedure, one stimulus (CS+) was paired with an electric shock (US), whereas another stimulus was not paired with the shock (CS-). The next day, participants underwent extinction training including presentations of the CS-, CS+ and a series of morphed stimuli between the CS- and CS+. In the hierarchical extinction condition (HE; N = 32), participants were first presented with the CS-, subsequently with the morph most similar to the CS-, then with the morph most similar to that one, and so forth, until reaching the CS+. In the random extinction condition (RE; N = 32), the same stimuli were presented but in a random order. Fear responding to the CS+, CS- and a new generalization stimulus (GS) was measured on the third day. Higher expectancy violation, t(62) = -2.67, p = .01, physiological arousal, t(62) = -2.08, p = .04, and variability in US-expectancy ratings, t(62) = -2.25, p = .03, were observed in the RE condition compared to the HE condition, suggesting the validity of this novel procedure. However, no differences between the RE and HE condition were found in fear responding as tested one day later, F(1, 62) < 1. In conclusion, we did not find evidence for differential long-term fear responding in modeling hierarchical versus random exposure in Pavlovian fear extinction.

Ruining the surprise: The effect of safety information before extinction on return of fear.

BACKGROUND AND OBJECTIVES: In psychoeducation before exposure treatment patients are sometimes provided with information about the (low) probability that the feared outcome would occur. Since it has been proposed in the literature that this might have adverse effects, the current study investigated the effect of providing participants with this type of safety information on return of fear. METHOD: In an ABA-renewal paradigm, participants in the experimental group were instructed between acquisition and extinction that the probability of US-occurrence would be extremely small in the remainder of the experiment. Participants in the control group did not receive this information. RESULTS: Less return of fear in US-expectancy ratings was observed in participants who received the safety information. LIMITATIONS: We failed to find successful acquisition in the skin-conductance data, which prevented us from interpreting the results of this outcome measure. CONCLUSIONS: These results suggest that providing safety information is not deleterious for the effects of exposure and can even be beneficial for its effects. However, further clinical research is needed.

Virtually Unexpected: No Role for Expectancy Violation in Virtual Reality Exposure for Public Speaking Anxiety.

In the current study, we examined the role of expectancy violation and retrospective reasoning about the absence of feared outcomes in virtual reality exposure therapy (VRET). Participants fearful of public speaking were asked to give speeches in virtual reality. We asked each participant individually to report their expectancies about feared outcomes in public speaking situations and which of these could be tested in VRET. Each of the expectancies was categorized as being related to: (1) participants' own reactions, (2) (overt) reactions of the audience, or (3) (covert) negative evaluation. We examined whether the proportion of testable expectancies could predict treatment outcome and which type of expectancies were evaluated as being more testable in VRET. Additionally, we experimentally manipulated retrospective reasoning about whether or not expectancies related to the overt reactions of the audience could be violated by providing verbal information after VRET about whether or not the virtual audience was interactive. A reduction in public speaking anxiety was observed from pre- to post-VRET. Treatment effects were, however, not predicted by the individually reported proportions of testable expectancies. Participants evaluated expectancies about their own reactions as being more testable in VRET compared to expectancies about reactions of the audience or about being negatively evaluated. In addition, we did not find evidence that the experimental manipulation regarding whether or not the audience was interactive influenced treatment effects. In conclusion, the results of the current study suggest that the effects of VRET are not univocally explained by the mechanism of expectancy violation.

One for all: The effect of extinction stimulus typicality on return of fear.

BACKGROUND AND OBJECTIVES: During exposure therapy, patients are encouraged to approach the feared stimulus, so they can experience that this stimulus is not followed by the anticipated aversive outcome. However, patients might treat the absence of the aversive outcome as an 'exception to the rule'. This could hamper the generalization of fear reduction when the patient is confronted with similar stimuli not used in therapy. We examined the effect of providing information about the typicality of the extinction stimulus on the generalization of extinction to a new but similar stimulus. METHODS: In a differential fear conditioning procedure, an animal-like figure was paired with a brief electric shock to the wrist. In a subsequent extinction phase, a different but perceptually similar animal-like figure was presented without the shock. Before testing the generalization of extinction with a third animal-like figure, participants were either instructed that the extinction stimulus was a typical or an atypical member of the animal family. RESULTS: The typicality instruction effectively impacted the generalization of extinction; the third animal-like figure elicited lower shock expectancies in the typical relative to the atypical group. LIMITATIONS: Skin conductance data mirrored these results, but did not reach significance. CONCLUSION: These findings suggest that verbal information about stimulus typicality can be a promising adjunctive to standard exposure treatments.

The validity of laboratory-based treatment research: Bridging the gap between fear extinction and exposure treatment.

A major objective of experimental psychopathology research is to improve clinical practice via the experimental study of treatment mechanisms. The success of this endeavor depends on the external validity of the procedures used to model the treatment component in the laboratory. We propose a general framework and a set of specific criteria that will allow evaluating whether a certain laboratory procedure is a valid model for a certain clinical treatment. We illustrate this framework by evaluating the validity of extinction as a laboratory model for clinical exposure therapy. Although we acknowledge the merits of the extinction model, we argue that its validity might not be as firmly established as the research community assumes. We also use extinction as an example to demonstrate how considerations of the proposed criteria can stimulate further improvements to existing models of treatment. We conclude that the systematic assessment of external validity of treatment models is an important step towards bridging the gap between science and practice in the field of experimental psychopathology.