The repeated confrontation with videotapes of spiders in multiple contexts attenuates renewal of fear in spider-anxious students

In a treatment-analogue experiment, extinction of fear of spiders was investigated in a group of spider-anxious students. Two groups were created: in the single extinction group the extinction trials consisted of repeated presentations of a videotaped spider in one specific location of a house, whereas in the multiple extinction group the trials consisted of videotapes of the same spider in three different locations of a house. Also a control group was included that was exposed to videotapes of the location but without the spider. As reflected in skin conductance responses and self-report data, fear of spiders was significantly reduced in the two extinction groups compared to the control group. Moreover, when the extinction groups were confronted with the videotape of the spider in a new location, the single extinction group did not show generalisation of extinction, whereas the multiple extinction group did. These results corroborate the existing evidence for context dependence of extinction of fear and provide new evidence that the use of multiple contexts during extinction might improve the generalisability of extinction in humans. Implications for exposure therapy are discussed.     

Return of fear in a human differential conditioning paradigm caused by a return to the original acquistion context

In a differential human fear conditioning paradigm evidence for ABA-renewal was obtained manipulating the lighting in the experimental room. During acquisition in either a dark or illuminated room, one neutral slide was sometimes paired with a loud aversive noise whereas another slide was not. Subsequently, extinction took place in the opposite lighting context. When afterwards the participants were tested again in the original acquisition context, measurements revealed a recovery of the conditioned electrodermal response and an increase in the retrospective verbal US-expectancy ratings. No response recovery was obtained in an AAA-group that received acquisition, extinction and test trials in one and the same context. Several theoretical explanations for this type of return of fear as well as implications for clinical practice are discussed.     

Contextual control of human fear associations in a renewal paradigm

The original model of behavior change suggests that extinction is context dependent whereas fear acquisition is context independent [Bouton, M. E. & Ricker, S. T. (1994). Renewal of extinguished responding in a second context. Animal Learning and Behavior, 22, 317-324]. Supportive evidence stems mainly from animal studies, showing that after acquisition (conditioned stimulus-unconditioned stimulus (CS-US)) in Context A and extinction in Context B, fear is renewed by presenting the CS in acquisition Context A (ABA renewal) or in a novel Context C (ABC renewal). By implication, the model predicts equal ABA and ABC renewal. However, there is also evidence to suggest that the context dependency of extinction and the context independency of acquisition may be less stringent than originally proposed. The present study investigated renewal in humans using a differential fear conditioning paradigm with a shock US and online shock expectancy ratings and electrodermal responses as dependent variables. Experiment 1 compared an ABA condition with an AAA condition. Experiment 2 compared three conditions: ABA, ABC, and AAA. Both experiments demonstrated ABA renewal. Most importantly, Experiment 2 showed larger ABA than ABC renewal. Overall, results for expectancy ratings were more convincing than for electrodermal responses. In line with the extinction model, the present findings support the context dependency of extinction in humans. In contrast to the model, the findings suggest that in humans not only extinction learning, but also fear acquisition is controlled by its current context.     

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.     

A randomized controlled trial of the effect of D-cycloserine on extinction and fear conditioning in humans

Previous research has shown that D-cycloserine (DCS) facilitates extinction of Pavlovian fear conditioning in rats and enhances exposure therapy in humans. The aim of this study was to test the effect of DCS on extinction of fear conditioning in humans. In three experiments, 238 participants were given either DCS (50 or 500 mg) or placebo 2-3 h before extinction training following a differential shock conditioning paradigm. Clear extinction and recovery (return of fear) effects were observed on both skin conductance and self-reported shock expectancy measures in three studies. DCS had no influence on these effects. The same pattern was observed when the analysis was restricted to aware participants or to good conditioners, when fear-relevant cues (pictures of snakes) were used as the conditioned stimuli, or when analysis was restricted to heightened snake-fearful participants. These results suggest that DCS may not enhance the extinction, or prevent the recovery, of learned fear in a differential Pavlovian conditioning paradigm in humans. Further experimental research is needed to better understand the mechanisms underlying the therapeutic effects of DCS.     

An examination of the decline in fear and disgust during exposure-based treatment

It has been suggested that disgust plays a prominent role in the fear of spiders. Participants (N=27) displaying marked spider fear were provided 30 min of self-directed in vivo exposure to an actual tarantula, during which time their fear and disgust levels were assessed repeatedly. Growth curve analyses were then conducted to examine the decay slopes in both fear and disgust and their relationship. Consistent with prediction, exposure led to significant declines in both spider fear and spider-specific disgust but not in global disgust sensitivity. However, the decay slope observed for fear was significantly greater than that for disgust. Further analyses revealed that the reduction in disgust during treatment remained significant even after controlling for change in fear; and similarly, change in fear remained significant even after controlling for change in disgust. Contrary to prediction, disgust levels at pretreatment did not moderate the level of fear activation or fear reduction during treatment. Theoretical and clinical implications of the findings are discussed.     

Fear expression and return of fear following threat instruction with or without direct contingency experience

Prior research showed that mere instructions about the contingency between a conditioned stimulus (CS) and an unconditioned stimulus (US) can generate fear reactions to the CS. Little is known, however, about the extent to which actual CS–US contingency experience adds anything beyond the effect of contingency instructions. Our results extend previous studies on this topic in that it included fear potentiated startle as an additional dependent variable and examined return of fear (ROF) following reinstatement. We observed that CS–US pairings can enhance fear reactions beyond the effect of contingency instructions. Moreover, for all measures of fear, instructions elicited immediate fear reactions that could not be completely overridden by subsequent situational safety information. Finally, ROF following reinstatement for instructed CS+s was unaffected by actual experience. In summary, our results demonstrate the power of contingency instructions and reveal the additional impact of actual experience of CS–US pairings.     

Fear conditioning in posttraumatic stress disorder: evidence for delayed extinction of autonomic, experiential, and behavioural responses

Aversive conditioning has been proposed as an important factor involved in the etiology of posttraumatic stress disorder (PTSD). However, it is not yet fully understood exactly which learning mechanisms are characteristic for PTSD. PTSD patients (n=36), and healthy individuals with and without trauma exposure (TE group, n=21; nTE group, n=34), underwent a differential fear conditioning experiment consisting of habituation, acquisition, and extinction phases. An electrical stimulus served as the unconditioned stimulus (US), and two neutral pictures as conditioned stimuli (CS+, paired; CS-, unpaired). Conditioned responses were quantified by skin conductance responses (SCRs), subjective ratings of CS valence and US-expectancy, and a behavioural test. In contrast to the nTE group, PTSD patients showed delayed extinction of SCRs to the CS+. Online ratings of valence and US-expectancy as well as the behavioural test confirmed this pattern. These findings point to a deficit in extinction learning and highlight the role of affective valence appraisals and cognitive biases in PTSD. In addition, there was some evidence that a subgroup of PTSD patients had difficulties in learning the CS-US contingency, thereby providing preliminary evidence of reduced discrimination learning.     

疼痛恐惧的形成、泛化与消退

疼痛恐惧源于把疼痛等同于伤害的灾难化信念及对疼痛的负性解释, 它在慢性疼痛和能力丧失的发生和发展过程中起着重要作用。疼痛恐惧可以通过联合学习和观察学习等方式获得, 并且在具有相似特征的刺激中存在泛化现象。通过教育干预和等级暴露疗法等可以成功消退疼痛恐惧, 在消退过程中要控制安全信息等因素的不良影响。在疼痛恐惧的获得与消退中, 主要有杏仁核, 脑岛和前扣带皮层等脑区参与。未来的研究可以集中在深入探讨疼痛恐惧形成中的泛化及消退后的恢复、再巩固等现象, 加强其临床上的应用, 并综合心理、生物和认知神经科学, 研究疼痛恐惧的获得、泛化与消退的深层机制。     

Utility of virtual reality environments to examine physiological reactivity and subjective distress in adults who stutter

PurposeVirtual reality environments (VREs) allow for immersion in speaking environments that mimic real-life interactions while maintaining researcher control. VREs have been used successfully to engender arousal in other disorders. The purpose of this study was to investigate the utility of virtual reality environments to examine physiological reactivity and subjective ratings of distress in persons who stutter (PWS).MethodSubjective and objective measures of arousal were collected from 10 PWS during four-minute speeches to a virtual audience and to a virtual empty room.ResultsStuttering frequency and physiological measures (skin conductance level and heart rate) did not differ across speaking conditions, but subjective ratings of distress were significantly higher in the virtual audience condition compared to the virtual empty room.ConclusionVREs have utility in elevating subjective ratings of distress in PWS. VREs have the potential to be useful tools for practicing treatment targets in a safe, controlled, and systematic manner.     

All we need is a cue to remember: the effect of an extinction cue on renewal

In the present study, it was investigated by employing a human fear conditioning paradigm whether an extinction retrieval cue can attenuate renewal of conditioned responding after an extinction treatment procedure, and if so, what the precise role of such an extinction cue comprises. It was hypothesized that such a cue can attenuate renewal and would function as a safety signal capable of directly inhibiting the expectancy of an aversive outcome and conditioned skin conductance responding to a conditioned stimulus. The results demonstrated that the extinguished expectancy of an aversive outcome was renewed when the CS was presented outside the extinction context and that an extinction cue attenuated this effect. This extinction cue, however, only transferred its inhibitory properties to other, non-extinguished stimuli when there was no contextual switch. This safety signal function was not observed after a switch in context. Possible functions of the extinction cue and its application in extinction-based exposure treatments are discussed.     

Exposure to a novel context after extinction causes a renewal of extinguished conditioned responses: Implications for the treatment of fear

Renewal gives an experimental model for the relapse of fear symptoms following exposure therapy. While renewal of extinguished fear in humans has been observed following a return to the original context in which fear was acquired (ABA design), it has been more difficult to show upon presentation of a novel context (ABC design). The present experiment used a particularly strong context manipulation in a fear conditioning procedure. Context was manipulated by using large photographs of real environments taken from various angles and was present throughout the entire experiment. A renewal of cognitive expectancy was found in both ABA and ABC renewal designs, although it was larger in the former than in the latter. Response times in making the expectancy judgments increased when there was a change to a new context. The results demonstrate consistency in fear renewal effects between human and animal studies and suggest that relapse following exposure therapy via renewal remains a danger when people encounter a previously feared object in a novel context.     

The effects of safety-seeking behavior and guided threat reappraisal on fear reduction during exposure: an experimental investigation

We examined the effects of safety-seeking behavior and guided threat focus and reappraisal on fear reduction during exposure. Participants (N=46) displaying marked claustrophobic fear were randomized to one of three 30-min exposure conditions: (a) guided threat focus and reappraisal; (b) safety-behavior utilization; or (c) exposure only control. Tripartite outcome assessments during a behavioral approach test, along with measures of suffocation and restriction fears were obtained at pre- and post-treatment, and at a 2-week follow-up. Treatment process measures were collected throughout treatment and consisted of indices of fear activation; within and between-trial fear habituation; and suffocation and entrapment expectancies. Measures of safety behavior utilization and attentional focus were also collected to assess the integrity of the experimental manipulations. Consistent with prediction, those encouraged to utilize safety-behaviors during exposure showed significantly more fear at post-treatment and follow-up relative to those encouraged to focus and reevaluate their core threat(s) during exposure. Moreover, growth curve analyses of treatment process data analyses revealed that safety-behavior utilization exerted a detrimental effect on between-trial habituation; whereas guided threat reappraisal enhanced between-trial habituation.     

Dissociative effects of flooding on a multivariate assessment of fear reduction and on jump-up avoidance extinction

Two experiments examined the effectiveness of three different amounts of flooding on hastening extinction of a jump-up avoidance response and on reducing fear as assessed by the multivariate fear assessment techniques of D. P. Corriveau and N. F. Smith (Journal of Experimental Psychology: General, 1978, 107, 145–158). In Experiment 1, a 40-min flooding treatment significantly hastened jump-up avoidance extinction, 10 min of flooding had a marginal effect, and 5 min had no effect. In Experiment 2, flooding treatments of 5, 10, and 40 min duration were all effective in reducing fear of the grid floor as indexed by seven of our nine dependent measures, including approach latency, safety test latency, and amount of time spent on the grids. Flooded subjects that were dumped onto the grid floor once at the start of the fear observation phase were found to show somewhat more fear reduction than were flooded subjects that were simply placed on the ledge at the outset of the fear observation phase and never dumped. These results, i.e., less flooding is required to reduce fear than to hasten avoidance extinction, are contrasted with those of previous experiments indicating that more flooding may be required to reduce fear than to hasten shuttlebox avoidance extinction. Such differences are discussed in the context of SSDR theory.     

The tripartite model of fear in children with specific phobias: assessing concordance and discordance using the behavioral approach test

Lang’s tripartite model posits that three main components characterize a fear response: physiological arousal, cognitive (subjective) distress, and behavioral avoidance. These components may occur in tandem with one another (concordance) or they may vary independently (discordance). The behavioral approach test (BAT) has been used to simultaneously examine the three components of the fear response. In the present study, 73 clinic-referred children and adolescents with a specific phobia participated in a phobia-specific BAT. Results revealed an overall pattern of concordance: correlation analyses revealed the three indices were significantly related to one another in the predicted directions. However, considerable variation was noted such that some children were concordant across the response components while others were not. More specifically, based on levels of physiological arousal and subjective distress, two concordant groups (high arousal–high distress, low arousal–low distress) and one discordant (high arousal–low distress or low arousal–high distress) group of youth were identified. These concordant and discordant groups were then compared on the percentage of behavioral steps completed on the BAT. Analyses revealed that the low arousal–low distress group completed a significantly greater percentage of steps than the high arousal–high distress group, and a marginally greater percentage of steps than the discordant group. Potential group differences associated with age, gender, phobia severity, and phobia type were also explored and no significant differences were detected. Implications for theory and treatment are discussed.     

Manifestations, acquisition and diagnostic categories of dental fear in a self-referred population

This study aimed to clarify how manifestations and acquisition relate to diagnostic categories of dental fear in a population of self-referred dental fear patients, since diagnostic criteria specifically related to dental fear have not been validated. DSM III-R diagnostic criteria for phobias were used to compare with four existing dental fear diagnostic categories, referred to as the Seattle system. Subjects were 208 persons with dental fear who were telephone interviewed, of whom a subsample of 155 responded to a mailed Dental Anxiety Scale (DAS), State-Trait Anxiety Inventory and a modified FSS-II Geer Fear Scale (GFS). Personal interviews and a Dental Beliefs Scale of perceived trust and social interaction with dentists were also used to evaluate a subsample of 80 patients selected by sex and high dental fear. Results showed that the majority of the 80 patients (66%), suffered from social embarrassment about their dental fear problem and their inability to do something about it. The largest cause of their fear (84%) was reported to be traumatic dental experiences, especially in childhood (70%). A minority of patients (16%) could not isolate traumatic experiences and had a history of general fearfulness or anxiety. Analysis of GFS data for the 155 subjects showed that fear of snakes and injuries were highest among women; heights and injections among men. Fear of blood was rarely reported. Spearman correlations between GFS individual items and DAS scores indicated functional independence between dental fear and common fears such as blood, injections and enclosures in most cases. Only in specific types of dental fear did these results support Rachman and Lopatka's contention that fears are thought to summate.(ABSTRACT TRUNCATED AT 250 WORDS)     

Factor structure,validity, and reliability of the fear questionnaire in a Hong Kong Chinese population

This study examined the factor structure, validity, and reliability of the Fear Questionnaire in Hong Kong. The sample consisted of 226 college students who were ethnic Chinese and they came from different parts of Hong Kong. Exploratory factor analysis produced three meaningful factors. Confirmatory factor analysis supported the three-factor model of Marks and Mathews (1979) in the present sample of subjects. Findings also showed that the Fear Questionnaire was both reliable and valid. Limitations of the study and implications for future research in this area were discussed. In particular, the need to assess the cross-cultural application of the Fear Questionnaire was stressed.This research project was supported by the Research and Conference Grants of the University of Hong Kong.     

Increasing CREB in the auditory thalamus enhances memory and generalization of auditory conditioned fear

Although the lateral nucleus of the amygdala (LA) is essential for conditioned auditory fear memory, an emerging theme is that plasticity in multiple brain regions contributes to fear memory formation. The LA receives direct projections from the auditory thalamus, specifically the medial division of the medial geniculate nucleus (MGm) and adjacent posterior intralaminar nucleus (PIN). While traditionally viewed as a simple relay structure, mounting evidence implicates the thalamus in diverse cognitive processes. We investigated the role of plasticity in the MGm/PIN in auditory fear memory. First we found that auditory fear conditioning (but not control manipulations) increased the levels of activated CREB in both the MGm and PIN. Next, using viral vectors, we showed that exogenously increasing CREB in this region specifically enhanced formation of an auditory conditioned fear memory without affecting expression of an auditory fear memory, formation of a contextual fear memory, or basic auditory processing. Interestingly, mice with increased CREB levels in the MGm/PIN also showed broad auditory fear generalization (in contrast to control mice, they exhibited fear responses to tones of other frequencies). Together, these results implicate CREB-mediated plasticity in the MGm/PIN in both the formation and generalization of conditioned auditory fear memory. Not only do these findings refine our knowledge of the circuitry underlying fear memory but they also provide novel insights into the neural substrates that govern the degree to which acquired fear of a tone generalizes to other tones.     

The efficacy of videotape feedback for enhancing the effects of exposure-based treatment for social anxiety disorder: a controlled investigation

Correcting patients' faulty beliefs concerning social evaluative threats is the hallmark of cognitive-behavioral treatment of social anxiety disorder. The current study examined the efficacy of two videotape feedback procedures as adjuncts to exposure-based treatment. Participants suffering from social phobia (N=77) were randomly assigned to one of four conditions: (a) credible placebo treatment (PLA); (b) exposure + no feedback (EXP); (c) exposure + videotape feedback of performance (PER); or (d) exposure + videotape feedback of audience responses (AUD). Contrary to prediction, the videotape feedback procedures did not enhance the effects of exposure-based treatment. Clinical and theoretical implications are discussed.