Empathy does not amplify vicarious threat learning

Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes

Introduction

Observational learning (OL) refers to learning through observing other people's behavior. OL has been suggested as an effective and simple tool to evoke treatment expectations and corresponding placebo and nocebo effects. However, the exact mechanisms by which OL shapes treatment outcomes, its moderating factors and possible areas of application remain unclear. We thus reviewed the existing literature with two different literature searches to answer the following questions: Which influencing factors contribute to OL-induced placebo and nocebo effects (in healthy volunteers and patients) and how large are these effects (search 1)? In which medical fields has OL been used so far to modulate treatment expectancy and treatment outcomes in patients, their caregivers, and at-risk groups (search 2)? We also aimed to explore whether and how the assessment of treatment expectations has been incorporated.

Methods

We conducted two independent and comprehensive systematic literature searches, both carried out on September 20, 2022.

Results

We identified 21 studies that investigated OL-mediated placebo and nocebo effects for pain and itch, the (placebo) efficacy of sham treatment on anxiety, and the (nocebo) induction of medication side effects (search 1). Studies showed that OL can efficiently induce placebo and nocebo effects across different presentation modes, with medium effect sizes on average: placebo effects, d = 0.79 (range: d = -0.36-1.58), nocebo effects, d = 0.61 (range: d = 0.04-1.5). Although several moderating factors have been investigated, their contribution to OL-induced effects remains unclear because of inconsistent results. Treatment expectation was assessed in only four studies. Regarding medical applications of OL (search 2), we found 12 studies. They showed that OL was effectively applied in preventive, therapeutic and rehabilitative interventions and that it was mainly used in the field of psychosomatics.

Discussion

OL effects on treatment outcomes can be both positive and negative. Future research should investigate which individuals would benefit most from OL and how OL can be implemented most effectively to induce placebo and avoid nocebo effects in clinical settings.

Systematic review registration

This work was preregistered at the Center for Open Science as open-ended registration (doi: 10.17605/OSF.IO/FVHKE). The protocol can be found here: https://archive.org/details/osf-registrations-fvhke-v1.

Impact of observational and direct learning on fear conditioning generalization in humans

Humans gain knowledge about threats not only from their own experiences but also from observing others' behavior. A neutral stimulus is associated with a threat stimulus for several times and the neutral stimulus will evoke fear responses, which is known as fear conditioning. When encountering a new event that is similar to one previously associated with a threat, one may feel afraid and produce fear responses. This is called fear generalization. Previous studies have mostly focused on fear conditioning and generalization based on direct learning, but few have explored how observational fear learning affects fear conditioning and generalization. To the best of our knowledge, no previous study has focused on the neural correlations of fear conditioning and generalization based on observational learning. In the present study, 58 participants performed a differential conditioning paradigm in which they learned the associations between neutral cues (i.e., geometric figures) and threat stimuli (i.e., electric shock). The learning occurred on their own (i.e., direct learning) and by observing other participant's responses (i.e., observational learning); the study used a within-subjects design. After each learning condition, a fear generalization paradigm was conducted by each participant independently while their behavioral responses (i.e., expectation of a shock) and electroencephalography (EEG) recordings or responses were recorded. The shock expectancy ratings showed that observational learning, compared to direct learning, reduced the differentiation between the conditioned threatening stimuli and safety stimuli and the increased shock expectancy to the generalization stimuli. The EEG indicated that in fear learning, threatening conditioned stimuli in observational and direct learning increased early discrimination (P1) and late motivated attention (late positive potential [LPP]), compared with safety conditioned stimuli. In fear generalization, early discrimination, late motivated attention, and orienting attention (alpha-event-related desynchronization [alpha-ERD]) to generalization stimuli were reduced in the observational learning condition. These findings suggest that compared to direct learning, observational learning reduces differential fear learning and increases the generalization of fear, and this might be associated with reduced discrimination and attentional function related to generalization stimuli.

Correlation between laboratory-based vicarious threat learning and emotional disorder symptom dimensions

BACKGROUND AND OBJECTIVES

Vicarious threat conditioning abnormalities are theorized to confer vulnerability to a wide range of emotional problems. We tested two different conceptual models of this non-specificity. First, hypersensitivity to socially conditioned danger cues might predict standing on a general internalizing dimension that represents commonalities among various forms of anxiety and depression. Second, this hypersensitivity might predict specific symptom clusters, such as panic or social anxiety.

METHODS

We examined university students' (N = 150) defensive responses during a vicarious threat conditioning task in relation to both broad and specific components of the internalizing domain.

RESULTS

Vicarious conditioning was successful, such that participants exhibited larger subjective and skin conductance responses during their first direct encounters with threatening, as compared to nonthreatening, conditioned stimuli. But, contrary to hypotheses, individual differences in this threat learning process were not robustly correlated with any internalizing dimension.

LIMITATIONS

The threat value of the conditioned stimuli was readily apparent, possibly limiting individual differences in defensive responding and, in turn, the correlations between conditioned responses and symptom dimensions. Also, results may differ in clinical populations.

CONCLUSIONS

Our findings suggest that the association between vicarious threat learning and emotional disorder risk-whether it is conceptualized in terms of broad symptom dimensions that span many categorical diagnoses or more fine-grain symptom processes-is weaker than previously believed, at least in this population. Data, analysis code, and stimulus materials are available at https://osf.io/m3xst/.

Watch and Learn: Vicarious Threat Learning across Human Development

Vicarious threat learning is an important pathway in learning about safety and danger in the environment and is therefore critical for survival. It involves learning by observing another person's (the demonstrator) fearful responses to threat and begins as early as infancy. The review discusses the literature on vicarious threat learning and infers how this learning pathway may evolve over human development. We begin by discussing the methods currently being used to study observational threat learning in the laboratory. Next, we focus on the social factors influencing vicarious threat learning; this is followed by a review of vicarious threat learning among children and adolescents. Finally, we examine the neural mechanisms underpinning vicarious threat learning across human development. To conclude, we encourage future research directions that will help elucidate how vicarious threat learning emerges and how it relates to the development of normative fear and pathological anxiety.

Excessive Object Attachment in Hoarding Disorder: Examining the Role of Interpersonal Functioning

Excessive attachment towards possessions can be maladaptive because it can lead individuals to excessively acquire and save objects. Little is known about how attachment to objects develops and changes over time; however, interpersonal factors have been theorized to play a role. The current study examined whether interpersonal factors, specifically interpersonal attachment style and empathy, moderate changes in object attachment over time. A total of 145 participants with excessive acquiring and discarding difficulties rated their level of attachment to a novel object just after receiving it, and 1 week later. Participants also completed measures of interpersonal anxious attachment and interpersonal functioning. We found that changes in object attachment over time were moderated by interpersonal anxious attachment. Also, our findings suggested that individuals with hoarding problems are likely not impaired in their ability to empathize with others, but rather have difficulty displaying empathy in tense social situations and also have more empathy for fictional characters. Further, greater discomfort in tense social situations and greater empathy for fictional characters interacted to predict greater object attachment. Taken together, these findings indicate that individuals with an interpersonal anxious attachment style may be those at risk of forming greater attachments to objects over time. A learning history that includes inconsistent support from caregivers may result in individuals experiencing more empathy for fictional characters and discomfort in tense social situations, which may produce a vulnerability for becoming excessively attached to objects. Our results are in line with theories of hoarding which propose that individuals use objects to compensate for unmet interpersonal needs and suggest that treatment may need to target interpersonal functioning to reduce hoarding symptoms.

Observational learning of fear in real time procedure

Learning to avoid threats often occurs by observing others. Most previous research on observational fear learning (OFL) in humans has used pre-recorded standardized video of an actor and thus lacked ecological validity. Here, we aimed to enhance ecological validity of the OFL by engaging participants in a real-time observational procedure (35 pairs of healthy male friends, age 18-27). One of the participants watched the other undergo a differential fear conditioning task, in which a conditioned stimulus (CS+) was paired with an aversive electric shock and another stimulus (CS-) was always safe. Subsequently, the CS+ and CS- were presented to the observer to test the OFL. While the friend's reactions to the shock elicited strong skin conductance responses (SCR) in all observers, subsequent differential SCRs (CS+ > CS-) were found only when declarative knowledge of the CS+/US contingency (rated by the participants) was acquired. Contingency-aware observers also showed elevated fear potentiated startle responses during both CS+ and CS- compared to baseline. We conclude that our real-time procedure can be effectively used to study OFL. The procedure allowed for dissecting two components of the OFL: an automatic emotional reaction to the response of the demonstrator and learning about stimulus contingency.