Renewal of fear and avoidance in humans to escalating threat: Implications for translational research on anxiety disorders

Rewarding Approach Behaviour Attenuates the Return of Pain-Related Avoidance After Successful Extinction with Response Prevention

After successful exposure treatment for chronic pain, pain-related fear and avoidance may return, i.e., relapse may occur. This return of fear and avoidance may be modulated by various post-treatment factors. In this study, we aimed to investigate two potential factors that may affect return of fear and avoidance, i.e. cognitive load and rewarding approach behaviour. In an operant pain-related avoidance conditioning paradigm, healthy pain-free volunteers first learned to fear and avoid an arm-reaching movement that was often paired with painful electrocutaneous stimulation (T1), by performing alternative movements that were less often (T2) or never (T3) paired with pain. During extinction with response prevention, participants were only allowed to perform T1, and pain was omitted. To model relapse, two unexpected painful stimuli were presented (i.e., reinstatement manipulation), after which participants could freely choose among the three arm-reaching movements again. During test, the Low Load group performed an additional easy digit task, whereas the High Load group performed a more cognitively demanding digit task. The Reward group performed the demanding digit task, whilst being rewarded to perform T1. Results showed that pain-related fear and avoidance returned, irrespective of cognitive load imposed. When participants were rewarded to approach T1, however, the return of avoidance, but not fear, was attenuated. Our findings suggest that engaging in rewarding activities may facilitate the maintenance of treatment outcomes, and provide additional support to the growing body of literature indicating a divergent relationship between fear and avoidance. PERSPECTIVE: Results of this experiment suggest that engaging in rewarding activities may optimize exposure treatment for chronic pain, by dampening the return of pain-related avoidance - though not of pain-related fear - after extinction.

Key factors behind various specific phobia subtypes

While it has been suggested that more than a quarter of the whole population is at risk of developing some form of specific phobia (SP) during their lives, we still know little about the various risk and protective factors and underlying mechanisms. Moreover, although SPs are distinct mental disorder categories, most studies do not distinguish between them, or stress their differences. Thus, our study was manifold. We examined the psychometric properties of the Specific Phobia Questionnaire (SPQ) and assessed whether it can be used for screening in the general population in a large sample (N = 685). Then, using general linear modeling on a second sample (N = 432), we tested how potential socio-demographic, cognitive emotion regulatory, and personality variables were associated with the five SP subtypes. Our results show that the SPQ is a reliable screening tool. More importantly, we identified transdiagnostic (e.g., younger age, female gender, rumination, catastrophizing, positive refocusing) as well as phobia-specific factors that may contribute to the development and maintenance of SPs. Our results support previous claims that phobias are more different than previously thought, and, consequently, should be separately studied, instead of collapsing into one category. Our findings could be pertinent for both prevention and intervention strategies.

Context-induced renewal of passive but not active coping behaviours in the shock-probe defensive burying task

Renewal is the return of extinguished responding after removal from the extinction context. Renewal has been extensively studied using classical aversive conditioning procedures that measure a passive freezing response to an aversive conditioned stimulus. However, coping responses to aversive stimuli are complex and can be reflected in passive and active behaviours. Using the shock-probe defensive burying task, we investigated whether different coping responses are susceptible to renewal. During conditioning, male, Long-Evans rats were placed into a specific context (Context A) where an electrified shock-probe delivered a 3 mA shock upon contact. During extinction, the shock-probe was unarmed in either the same (Context A) or a different context (Context B). Renewal of conditioned responses was assessed in the conditioning context (ABA) or in a novel context (ABC or AAB). Renewal of passive coping responses, indicated by an increased latency and a decreased duration of shock-probe contacts, was observed in all groups. However, renewal of passive coping, measured by increased time spent on the side of the chamber opposite the shock-probe, was only found in the ABA group. Renewal of active coping responses linked to defensive burying was not observed in any group. The present findings highlight the presence of multiple psychological processes underlying even basic forms of aversive conditioning and demonstrate the importance of assessing a broader set of behaviours to tease apart these different underlying mechanisms. The current findings suggest that passive coping responses may be more reliable indicators for assessing renewal than active coping behaviours associated with defensive burying.

No joy - why bother? Higher anhedonia relates to reduced pleasure from and motivation for threat avoidance

Anhedonia impairs various components of the pleasure cycle, including wanting, liking, and the learning of pleasure-related associations. While successfully controlling threats might be inherently pleasurable, it remains unclear whether anhedonia affects this form of pleasure as well. With aversive pictures as threats, we conducted an online study ( N = 200) to investigate the role of anhedonia during active avoidance learning process. Participants first learned cue-threat associations for different cues (threat vs. safety cues). In a subsequent avoidance learning phase, these cues signaled either avoidable, unavoidable, or no threat; participants could perform avoidance responses to prevent the upcoming threats during those cue presentations. Subjective relief pleasantness was measured after each threat omission. We found that higher trait anticipatory and consummatory anhedonia were both associated with lower relief pleasantness. Higher trait anticipatory anhedonia was also associated with fewer avoidance attempts. Since reduced threat-controlling behavior is reminiscent of a learned-helplessness state, the current results contribute to a better understanding of the connections between anhedonia and learned helplessness that have mostly been studied separately in the context of mood disturbance.

Conditional Control of Instrumental Avoidance by Context Following Extinction

Using rodents, three training arrangements (i.e., ABB vs. ABA, AAA vs. AAB and ABB vs. ABC) explored whether extinction influences the expression of avoidance in a manner controlled by context. Retention testing following extinction showed that more avoidance responding (i.e., renewal) was observed when extinguished cues were tested outside of the context where they had undergone extinction. In contrast, response rates were significantly lower when stimuli were tested within the context where extinction learning had occurred. These findings add to the emerging literature assessing the role of Pavlovian extinction processes in the development of instrumental avoidance responding by demonstrating conditional control over extinguished responding by context. This study was conducted using a within-subjects approach that minimized the potential for context-outcome associations to bias responding, and thus, reflects hierarchical control over behavior based on the specific associative status of each tested cue in each training context.

Human social defeat and approach-avoidance: Escalating social-evaluative threat and threat of aggression increases social avoidance

Basic research on avoidance by Murray Sidman laid the foundation for advances in the classification, conceptualization and treatment of avoidance in psychological disorders. Contemporary avoidance research is explicitly translational and increasingly focused on how competing appetitive and aversive contingencies influence avoidance. In this laboratory investigation, we examined the effects of escalating social-evaluative threat and threat of social aggression on avoidance of social interactions. During social-defeat learning, 38 adults learned to associate 9 virtual peers with an increasing probability of receiving negative evaluations. Additionally, 1 virtual peer was associated with positive evaluations. Next, in an approach-avoidance task with social-evaluative threat, 1 peer associated with negative evaluations was presented alongside the peer associated with positive evaluations. Approaching peers produced a positive or a probabilistic negative evaluation, while avoiding peers prevented a negative evaluation (and forfeited a positive evaluation). In an approach-avoidance task with social aggression, virtual peers gave and took money away from participants. Escalating social-evaluative threat and aggression increased avoidance, ratings of feeling threatened and threat expectancy and decreased ratings of peer favorableness. These findings underscore the potential of coupling social defeat and approach-avoidance paradigms for translational research on the neurobehavioral mechanisms of social approach-avoidance decision-making and anxiety.

Relapse of anxiety-related fear and avoidance: Conceptual analysis of treatment with acceptance and commitment therapy

Excessive fear and avoidance in relatively safe situations can lead to a narrowing of one's behavioral repertoire and less engagement with valued aspects of living. Ultimately, these processes can reach clinical levels, as seen in anxiety, trauma, and obsessive-compulsive disorders. Research on the basic behavioral processes underlying successful treatment with exposure therapy is growing, yet little is known about the mechanisms contributing to clinical relapse. Until recently, these mechanisms have largely been conceptualized in terms of Pavlovian return of fear, with relatively little research into operant processes. In the current paper, we briefly review translational research in anxiety disorders and the connections between fear and avoidance, focusing on recent work in the acquisition, extinction, and relapse of avoidance behavior and the generalization of this learning through arbitrary symbolic relations. We then introduce one possible treatment approach to mitigating clinical relapse, acceptance and commitment therapy (ACT), and provide a conceptual analysis for why ACT may be especially well-situated to address this issue. Finally, we end with potential directions for future research on treatment and relapse of anxiety disorders.