Non-fearful Participants Research Articles

Reality Cheque: Different Methods of Eliciting Fear-Related Beliefs Reveal Multiple Representations of Threat

Influential models of fears and phobias suggest that irrational threat beliefs underpin excessive fear. Yet, many fearful individuals recognize their fear is not justified. Drawing on memory competition/multiple representations theory, we developed a novel, fear-relevant procedure, which reveals conflicting representations of threat. In three experiments (Experiment 1, N = 49, Experiment 2, N = 47, Experiment 3, N = 75), fearful and non-fearful participants not only provided Probability Ratings for fear-related outcomes in a fear-relevant exposure task, but placed Bets, with payoffs depending on what happened in reality. Fearful participants displayed much higher Probability Ratings than Low fear participants. However, Bets revealed far less consistent group differences, even when proximal to threat (Experiments 1 and 2), and differences between High and Low fear participants’ Bets disappeared when they could not be anchored to previous Probability Ratings (Experiment 3). A Neutral Betting task also showed that general betting strategies were comparable between groups. We suggest that these findings may reflect the multi-representational nature of belief, in which both adaptive and maladaptive representations of a feared object may exist in parallel, with personal and contextual factors determining which form of representation is retrieved or expressed. This perspective can provide insights into the complex interplay of adaptive and maladaptive beliefs that is a central focus of currently dominant therapies.

Moving spiders do not boost visual search in spider fear

Previous research on attention to fear-relevant stimuli has largely focused on static pictures or drawings, and thus did not consider the potential effect of natural motion. Here, we aimed to investigate the effect of motion on attentional capture in spider-fearful and non-fearful participants by using point-light stimuli and naturalistic videos. Point-light stimuli consist of moving dots representing joints and thereby visualizing biological motion (e.g. of a walking human or cat) without needing a visible body. Spider-fearful (n = 30) and non-spider-fearful (n = 31) participants completed a visual search task with moving targets (point-light/naturalistic videos) and static distractors (images), static targets and moving distractors, or static targets and static distractors. Participants searched for a specified animal type (snakes, spiders, cats, or doves) as quickly as possible. We replicated previous findings with static stimuli: snakes were detected faster and increased distraction, while spiders just increased distraction. However, contrary to our hypotheses, spider targets did not speed up responses, neither in the group of control nor in the group of spider-fearful participants. Interestingly, stimuli-specific effects were toned down, abolished, or even changed direction when motion was introduced. Also, we demonstrated that point-light stimuli were of similar efficiency as naturalistic videos, indicating that for testing effects of motion in visual search, “pure” motion stimuli might be sufficient. As we do show a substantial modulation of visual search phenomena by biological motion, we advocate for future studies to use moving stimuli, equivalent to our dynamic environment, to increase ecological validity.

Temporal dynamics of costly avoidance in naturalistic fears: Evidence for sequential-sampling of fear and reward information

Excessive avoidance is characteristic for anxiety disorders, even when approach would lead to positive outcomes. The process of how such approach-avoidance conflicts are resolved is not sufficiently understood. We examined the temporal dynamics of approach-avoidance in intense fear of spiders. Highly fearful and non-fearful participants chose repeatedly between a fixed no spider/low reward and a spider/high reward option with varying fear (probability of spider presentation) and reward information (reward magnitude). By sequentially presenting fear and reward information, we distinguished whether decisions are dynamically driven by both information (sequential-sampling) or whether the impact of fear information is inhibited (cognitive control). Mouse movements were recorded to assess temporal decision dynamics (i.e., how strongly which information impacts decision preference at which timepoint). Highly fearful participants showed stronger avoidance despite lower gains (i.e., costly avoidance). Time-continuous multiple regression of their mouse movements yielded a stronger impact of fear compared to reward information. Importantly, presenting either information first (fear or reward) enhanced its impact during the early decision process. These findings support sequential sampling of fear and reward information, but not inhibitory control. Hence, pathological avoidance may be characterized by biased evidence accumulation rather than altered cognitive control.

Cue conditioning using a virtual spider discriminates between high and low spider fearful individuals

The fear conditioning paradigm is one of the most commonly used procedures to examine the etiology and treatment of anxiety disorders in laboratories. However, findings with this procedure often do not generalize to clinical settings. Virtual reality (VR) is a promising tool for improving the ecological and predictive validity of fear conditioning. The current study explored whether a classical differential cue conditioning paradigm with spider-fearful participants can be conducted in a VR-environment. Specifically, 25 spider-fearful and 25 non-fearful female students participated in a fear-conditioning experiment with a virtual spider as an unconditioned stimulus (US). The experiment took place in a virtual office in which participants viewed an avatar of themselves sitting at a desk. Conditioned stimuli (CS) were a blue (CS+; 100% reinforcement) and a green (CS-) light emitted by a desk lamp. Fear reactions were measured by fear ratings, skin conductance responses (SCR), and fear potentiated startle responses (FPS). Our results indicated stronger differential fear conditioning for spider-fearful participants than for non-fearful participants. Furthermore, we demonstrate that these results relate specifically to spider-fear, and not to general trait anxiety. We conclude that fear conditioning in VR is a promising tool to improve the validity of classical fear conditioning procedures.

The Set of Fear Inducing Pictures (SFIP): Development and validation in fearful and nonfearful individuals

Emotionally charged pictorial materials are frequently used in phobia research, but no existing standardized picture database is dedicated to the study of different phobias. The present work describes the results of two independent studies through which we sought to develop and validate this type of database—a Set of Fear Inducing Pictures (SFIP). In Study 1, 270 fear-relevant and 130 neutral stimuli were rated for fear, arousal, and valence by four groups of participants; small-animal (N = 34), blood/injection (N = 26), social-fearful (N = 35), and nonfearful participants (N = 22). The results from Study 1 were employed to develop the final version of the SFIP, which includes fear-relevant images of social exposure (N = 40), blood/injection (N = 80), spiders/bugs (N = 80), and angry faces (N = 30), as well as 726 neutral photographs. In Study 2, we aimed to validate the SFIP in a sample of spider, blood/injection, social-fearful, and control individuals (N = 66). The fear-relevant images were rated as being more unpleasant and led to greater fear and arousal in fearful than in nonfearful individuals. The fear images differentiated between the three fear groups in the expected directions. Overall, the present findings provide evidence for the high validity of the SFIP and confirm that the set may be successfully used in phobia research.

Enhanced discriminative fear learning of phobia-irrelevant stimuli in spider-fearful individuals.

Avoidance is considered as a central hallmark of all anxiety disorders. The acquisition and expression of avoidance, which leads to the maintenance and exacerbation of pathological fear is closely linked to Pavlovian and operant conditioning processes. Changes in conditionability might represent a key feature of all anxiety disorders but the exact nature of these alterations might vary across different disorders. To date, no information is available on specific changes in conditionability for disorder-irrelevant stimuli in specific phobia (SP). The first aim of this study was to investigate changes in fear acquisition and extinction in spider-fearful individuals as compared to non-fearful participants by using the de novo fear conditioning paradigm. Secondly, we aimed to determine whether differences in the magnitude of context-dependent fear retrieval exist between spider-fearful and non-fearful individuals. Our findings point to an enhanced fear discrimination in spider-fearful individuals as compared to non-fearful individuals at both the physiological and subjective level. The enhanced fear discrimination in spider-fearful individuals was neither mediated by increased state anxiety, depression, nor stress tension. Spider-fearful individuals displayed no changes in extinction learning and/or fear retrieval. Surprisingly, we found no evidence for context-dependent modulation of fear retrieval in either group. Here, we provide first evidence that spider-fearful individuals show an enhanced discriminative fear learning of phobia-irrelevant (de novo) stimuli. Our findings provide novel insights into the role of fear acquisition and expression for the development and maintenance of maladaptive responses in the course of SP.

Mechanisms of visual threat detection in specific phobia

People with anxiety or stress-related disorders attend differently to threat-relevant compared with non-threat stimuli, yet the temporal mechanisms of differential allocation of attention are not well understood. We investigated two independent mechanisms of temporal processing of visual threat by comparing spider-phobic and non-fearful participants using a rapid serial visual presentation task. Consistent with prior literature, spider phobics, but not non-fearful controls, displayed threat-specific facilitated detection of spider stimuli relative to negative stimuli and neutral stimuli. Further, signal detection analyses revealed that facilitated threat detection in spider-phobic participants was driven by greater sensitivity to threat stimulus features and a trend towards a lower threshold for detecting spider stimuli. However, phobic participants did not display reliably slowed temporal disengagement from threat-relevant stimuli. These findings advance our understanding of threat feature processing that might contribute to the onset and maintenance of symptoms in specific phobia and disorders that involve visual threat information more generally.

Cynophobic fear adaptively extends peri-personal space.

Peri-personal space (PPS) is defined as the space immediately surrounding our bodies, which is critical in the adaptation of our social behavior. As a space of interaction with the external world, PPS is involved in the control of motor action as well as in the protection of the body. The boundaries of this PPS are known to be flexible but so far, little is known about how PPS boundaries are influenced by unreasonable fear. We hypothesized that unreasonable fear extends the neural representation of the multisensory space immediately surrounding the body in the presence of a feared object, with the aim of expanding the space of protection around the body. To test this hypothesis, we explored the impact of unreasonable fear on the size of PPS in two groups of non-clinical participants: dog-fearful and non-fearful participants. The sensitivity to cynophobia was assessed with a questionnaire. We measured participants’ PPS extent in the presence of threatening (dog growling) and non-threatening (sheep bleating) auditory stimuli. The sound stimuli were processed through binaural rendering so that the virtual sound sources were looming toward participants from their rear hemi-field. We found that, when in the presence of the auditory dog stimulus, the PPS of dog-fearful participants is larger than that of non-fearful participants. Our results demonstrate that PPS size is adaptively modulated by cynophobia and suggest that anxiety tailors PPS boundaries when exposed to fear-relevant features. Anxiety, with the exception of social phobia, has rarely been studied as a disorder of social interaction. These findings could help develop new treatment strategies for anxious disorders by involving the link between space and interpersonal interaction in the approach of the disorder.

Emotional effects on time-to-contact judgments: arousal, threat, and fear of spiders modulate the effect of pictorial content

Recently, responses to looming visual stimuli have been shown to depend on the emotional content of the stimulus. A threatening stimulus is judged to arrive sooner compared to a neutral stimulus, possibly buying the organism time to prepare defensive actions. Here, we explored the underlying mechanism. We found that time-to-contact judgments of threatening pictures did not differ from those of highly arousing pleasant pictures (Experiment 1), suggesting that arousal, not fear, modulates the perception of looming. Specific fear modulated the effects of arousal (Experiment 2): Spider-fearful participants' judgments showed a threat advantage effect, while non-fearful participants' judgments were less affected by emotional content. In Experiment 3, arrival times were less overestimated when pictures induced arousal. However, this effect interacted with the valence of the stimulus: For unpleasant stimuli, arousal induced shorter time-to-contact judgments, whereas for pleasant stimuli, an inverted U-shaped relation was found. We propose a general content effect to explain the overestimation with neutral pictures: Pictorial content may draw visual attention to inner contours instead of to the outer edges of the picture. This could delay time-to-contact judgments according to the known size-arrival effect. Our results add to the growing literature examining affective influences on visual perception.

The Role of Domain-Specific Disgust Propensity in Behavioral Avoidance and Self-Reported Fainting Symptoms in Blood-Injection-Injury Phobia

Recent research has implicated the role of disgust in avoidance and fainting associated with blood-injection-injury (BII) phobia. While several studies suggest that disgust propensity has a ‘domain-specific’ association (e.g. animal-reminder disgust) with these features of BII phobia, other studies have found a more generalized association (e.g. animal reminder and core disgust). The present study attempts to address this inconsistency in the literature by utilizing in vivo behavioral exposure to examine the role of disgust in avoidance and fainting among BII fearful (n = 38) and non-fearful (n = 35) participants. Avoidance and fainting symptoms were assessed during exposure to threat-relevant (bloody gauze, severed deer leg) and threat-irrelevant (worm, cockroach) stimuli. Contrary to hypotheses, regression analyses revealed that when the stimulus was threat-relevant, disgust propensity did not predict avoidance above and beyond BII fear. However, when the stimulus was threat-irrelevant, generalized disgust propensity predicted avoidance. Further, generalized disgust propensity predicted fainting symptoms during exposure to threat-relevant and threat-irrelevant stimuli above and beyond BII fear, whereas animal-reminder disgust did not. Implications of these findings for conceptualizing the role of disgust propensity domains in avoidance and fainting associated with BII phobia are discussed.

The cost of fear: Avoidant decision making in a spider gambling task

Individuals with anxiety disorders typically avoid fear-relevant stimuli even if they miss potential rewards. However, few studies have accounted for such costs of fear-related avoidance in doing so. In this study, 51 spider fearful and 49 non-fearful participants completed the Spider Gambling Task, our modification of the Iowa Gambling Task, to investigate whether fear-relevant stimuli trigger avoidant decisions in the presence of potential rewards. In one version, advantageous choices were associated with pictures of spiders, whereas the same pictures were associated with disadvantageous choices in another version. Fearful participants generally avoided choices associated with pictures of spiders, which resulted in lower overall gains in the version with advantageous spider decks. Although this relative avoidance was sustained, fearful participants progressively approach more advantageous spider choices. These findings demonstrate that phobic fear results in irrational avoidant decisions which can result in considerable cost. Potential long-term rewards for approach may, however, diminish absolute avoidance behavior.

Effects of attention manipulations on motivated attention to feared and nonfeared negative distracters in spider fear

BackgroundWhen people view emotional and neutral pictures, the emotional pictures capture more attention than do neutral pictures. In support, studies with event-related potentials have shown that the early posterior negativity (EPN) and the late positive potential (LPP) to emotional versus neutral pictures are enhanced when pictures are attended. However, this motivated attention decreases when voluntary attention is directed away from the pictures. Most previous studies included only generally emotional pictures of either negative or positive valence. Because people with spider fear report intense fear of spiders, we examined whether directing attention away from emotional pictures at fixation decreases motivated attention less strongly for spiders than for generally negative distracters.ResultsWe recorded event-related potentials from 128 channels to study whether manipulations of attention (i.e., spatial attention and perceptual load) decrease the EPN and the LPP to emotional distracters less strongly for spiders than for fear-irrelevant negative pictures in people with spider fear. Results confirmed that the EPN and the LPP to spiders (vs. neutral pictures) were particularly enhanced in participants with spider fear compared to participants without spider fear. When attention was directed away from the pictures, the EPN and the LPP to spiders (vs. neutral pictures) decreased similarly in fearful and nonfearful participants. Further, in fearful participants, the decrease in the EPN and the LPP was similar for spiders and for fear-irrelevant negative pictures.ConclusionsOur findings suggest that for people with spider fear, directing attention away from emotional pictures at fixation decreases motivated attention to these distracters similarly for spiders as for fear-irrelevant negative pictures. These findings imply that attention to spiders in spider fear does not exceed the level of attention expected from the spider pictures’ high arousal and negative valence (i.e., their intrinsic motivated attention).

The effect of very brief exposure on experienced fear after in vivo exposure

Two experiments tested the effect of exposure to masked phobic stimuli at a very brief stimulus onset asynchrony on reducing the subjective experience of fear caused by in vivo exposure to a feared object. In the main experiment, 35 spider-fearful and 35 non-fearful participants were identified with a questionnaire and a Behavioural Avoidance Test (BAT) with a live tarantula. One week later, they were individually administered one of two continuous series of masked images: spiders or flowers. They engaged in the BAT again immediately thereafter. They provided ratings of subjective fear at the end of each BAT (pre- and post-manipulation). Very brief exposure to images of spiders reduced the fearful group's and not the non-fearful group's experience of fear at the end of the BAT. This effect was replicated with another sample of 26 spider-fearful participants from the same population. Theoretical implications are discussed.

The Effect of Using Different Distractor Sets in Visual Search with Spiders and Snakes on Spider-Sensitive and Nonfearful Participants

In two visual search experiments, we investigated the impact of distractor sets on fear-relevant stimuli by comparing a search set with spiders, snakes, flowers, and mushrooms to one with spiders, snakes, rabbits, and turtles. We found speeded responses to spider and snake targets when flowers and mushrooms, but not when rabbits and turtles served as distractors. In Experiment 2, we compared spider-sensitive to nonfearful participants. Spider-sensitive participants responded faster than nonfearful participants to spider targets when we used flowers and mushrooms as distractors, but not when we used rabbit and turtle distractors. These results indicate that behavioral responses to the visual search task not only depend on the individual’s relationship to the stimuli included in the search set, but also on the context in which the feared or fear-relevant objects are presented.

Auditory–Visual Aversive Stimuli Modulate the Conscious Experience of Fear

In a natural environment, affective information is perceived via multiple senses, mostly audition and vision. However, the impact of multisensory information on affect remains relatively undiscovered. In this study, we investigated whether the auditory-visual presentation of aversive stimuli influences the experience of fear. We used the advantages of virtual reality to manipulate multisensory presentation and to display potentially fearful dog stimuli embedded in a natural context. We manipulated the affective reactions evoked by the dog stimuli by recruiting two groups of participants: dog-fearful and non-fearful participants. The sensitivity to dog fear was assessed psychometrically by a questionnaire and also at behavioral and subjective levels using a Behavioral Avoidance Test (BAT). Participants navigated in virtual environments, in which they encountered virtual dog stimuli presented through the auditory channel, the visual channel or both. They were asked to report their fear using Subjective Units of Distress. We compared the fear for unimodal (visual or auditory) and bimodal (auditory-visual) dog stimuli. Dog-fearful participants as well as non-fearful participants reported more fear in response to bimodal audiovisual compared to unimodal presentation of dog stimuli. These results suggest that fear is more intense when the affective information is processed via multiple sensory pathways, which might be due to a cross-modal potentiation. Our findings have implications for the field of virtual reality-based therapy of phobias. Therapies could be refined and improved by implicating and manipulating the multisensory presentation of the feared situations.

Specific fear modulates attentional selectivity during visual search: Electrophysiological insights from the N2pc

In the present study, we used high-density EEG during a visual search task to investigate the dynamics of spatial attention to fear-relevant targets and background stimuli in small animal phobia during a visual search task. Twenty-five spider fearful (22 females) and 25 healthy nonfearful participants (19 females) were measured, while searching for discrepant objects in visual arrays. Compared to nonfearful participants, spider fearful individuals showed a more enhanced posterior N2pc to spider (vs. butterfly) targets in an array of flowers. Furthermore, spider fearful participants showed enhanced hypervigilance for all presented stimuli compared to controls as reflected by enhanced N1 amplitudes (160-200 ms). Our findings provide neural evidence for early, enhanced selective spatial attention for fear-relevant stimuli.

Emotional responses in spider fear are closely related to picture awareness

Theories of emotion propose that responses to emotional pictures can occur independently of whether or not people are aware of the picture content. Because evidence from dissociation paradigms is inconclusive, we manipulated picture awareness gradually and studied whether emotional responses varied with degree of awareness. Spider fearful and non-fearful participants viewed pictures of spiders and flowers at four levels of backward masking while electrodermal activity and heart rate were measured continuously. Recognition ratings confirmed that participants’ picture awareness decreased with masking. Critically, effects of spider fear on emotion ratings and heart rate also decreased with masking. These findings suggest that effects of spider fear on emotion ratings and heart rate are closely related to picture awareness.

Fear of Anxiety in Fearful Adults: An Analysis of Heterogeneity Among Phobia Types

Fear of anxiety, the fear of developing physiological symptoms associated with anxiety, is investigated in this study and the extent to which fear of anxiety is differentially present in the various subtypes of specific phobias. Participants were 260 undergraduate students divided into those having fears corresponding to one of the specific phobia types and those having no reported fears. Participants completed a variety of measures including the Agoraphobic Cognitions Questionnaire and the Body Sensations Questionnaire. Results indicated fearful participants had more fear of anxiety than non-fearful participants. In addition, non-fearful participants reported significantly less frequent catastrophic cognitions than fearful participants of the situational and other types. Non-fearful control participants also reported less fear of bodily sensations than fearful participants of the animal and other subtypes. This study provides supporting evidence that the phenomenon of fear of anxiety is present in fears similar to specific phobias.

What you cannot see can help you: The effect of exposure to unreportable stimuli on approach behavior

We examined effects of exposure to unreportable images of spiders on approach towards a tarantula. Pretests revealed awareness of the stimuli was at chance. Participants high or low (top and bottom 15%) on fear of spiders were randomly assigned to receive computer-generated exposure to unreportable pictures of spiders or outdoor scenes. They then engaged in a Behavioral Approach Task (BAT) with a live tarantula. Non-fearful participants completed more BAT items than spider-fearful individuals. Additionally, as predicted, a significant interaction (F(1,48)=5.12, p<.03) between fear of spiders and stimulus demonstrated that spider-fearful participants exposed to spiders completed more BAT items than spider-fearful participants exposed to control stimuli (but not as many as non-fearful participants). The findings support the hypothesis that exposure to unreportable feared stimuli promotes approach towards the feared object. Future research and clinical implications were discussed.

To look or not to look: An eye movement study of hypervigilance during change detection in high and low spider fearful students.

Previous eye movement studies of attentional bias in spider fear reported inconsistent results with respect to early attentional capture, suggesting that overt attentional capture only reliably occurs under specific circumstances. In addition, none of these studies explored covert attention. The present study examined attentional bias in spider phobia using a change detection paradigm that was expected to provide good conditions for documenting attentional capture. In contrast to our expectations, eye movement data showed that all participants' first fixations were fastest on general negative targets, whereas participants' first fixations on spider targets were slower in the spider fearful than in the nonfearful group. In addition, spider fearful participants made more nontarget fixations before fixating on a spider target than did nonfearful participants. Thus, we found that participants' overt attention was more quickly focused on general negative targets, whereas covert attentional processes enabled initial avoidance of fear-relevant (i.e. spider) stimuli. The present findings have important implications for research on attention and fear as they indicate that fearful individuals are not characterized by static attentional orienting toward threat but, under certain conditions, may avert attention from threat automatically.