Multimodal classical conditioning of fear: contributions of direct, observational, and verbal experiences to current fears

The authors propose that a multimodal classical conditioning model be considered when clinicians or clinical researchers study the etiology of fears and anxieties learned by human beings. They argue that fears can be built through the combined effects of direct, observed, and verbally presented classical conditioning trials. Multimodal classical conditioning is offered as an alternative to the three pathways to fear argument prominent in the human fear literature. In contrast to the three pathways position, the authors present theoretical arguments for why "learning by observation" and "learning through the receipt of verbal information" should be considered classical conditioning through observational and verbal modes. The paper includes a demonstration of how data, commonly collected in research on the three pathways to fear, would be studied differently using a multimodal classical conditioning perspective. Finally, the authors discuss implications for assessment, treatment, and prevention of learned fears in humans.     

Characteristics of individuals with fear of spiders

Abstract

This paper reports the results of two studies which investigated some of the factors that differentiated individuals with fear of spiders from those without such fears. The main results suggested that (a) there was little evidence that fear of spiders in nonclinical subjects is normally acquired through direct conditioning experiences; (b) there was some evidence for a familial component to spider fears; (c) there was no support for the view that individuals reporting a fear of spiders were especially sensitized to the movement cues possessed by spiders; (d) fear of spiders was not associated either with higher levels of trait anxiety or with an increased predisposition to other fears in general; but (e) fear of spiders did appear to be associated with increased fear of other animals, but only animals that are normally considered fear-evoking or disgust-evoking. These results provide little support for a traditional conditioning view of spider fears, and they are not entirely consistent with some preparedness accounts of the acquisition of specific fears. However, the results do suggest that fear of spiders is part of a functionally integrated set of animal fears, and it is argued that the present results could be better understood by attempting to integrate predator-defence and disease-avoidance models of animal fears.     

Non-associative fear acquisition: a review of the evidence from retrospective and longitudinal research

It is axiomatic that the capacity to experience fear is adaptive, enabling rapid and energetic response to imminent threat or danger. Despite the generally accepted utility of functional fear, the nature of maladaptive fear remains controversial. There is still no consensus about how specific fears and phobias are acquired and modulated. Two major schools of thought are apparent: those suggesting dysfunctional fear arises largely as the result of associative-conditioning processes versus those who favour more biologically based etiological explanations. In this regard, the non-associative model of fear acquisition postulates the existence of a limited number of innate, evolutionary-relevant fears, while emphasising conditioning modes of onset for evolutionary-neutral fears. Recent retrospective and longitudinal studies have tested predictions from the non-associative model. In general, findings support non-associative hypotheses and are difficult to reconcile with neo-conditioning explanations of fear acquisition. These data suggest that four pathways to fear may provide the most parsimonious theory of fear etiology. The theoretical and practical implications of adding a fourth, non-associative path to Rachman's (Behav. Res. Ther. (1977) 15, 375-387) three 'associative' pathways are discussed. Unresolved issues requiring further investigation are considered.     

Cross-US reinstatement of human conditioned fear: Return of old fears or emergence of new ones?

Re-exposure to the unconditioned stimulus (US) following fear extinction in the laboratory produces reinstatement of fear. Similarly in clinical situations, anxiety patients may experience adverse events that reinstate fear following successful exposure therapy. The current study employed two USs, shock and loud noise, to examine whether a US that is qualitatively different but of the same valence as the original acquisition US can produce reinstatement in human fear conditioning. Both standard and cross-US reinstatement manipulations led to elevated fear as indexed by skin conductance. However, cross-US reinstatement was accompanied by elevated expectancy of the US that had been presented during the reinstatement manipulation, not the US that had been used to establish fear in acquisition. This result implies that reinstatement may involve the development of new fears. Context conditioning and cognitive processes were implicated as possible mechanisms. The current findings suggest that clinical relapse attributed to reinstatement may not always reflect the reactivation of old fears but may instead represent new fears worthy of clinical examination.     

A comparison of positive vicarious learning and verbal information for reducing vicariously learned fear

Research with children has demonstrated that both positive vicarious learning (modelling) and positive verbal information can reduce children's acquired fear responses for a particular stimulus. However, this fear reduction appears to be more effective when the intervention pathway matches the initial fear learning pathway. That is, positive verbal information is a more effective intervention than positive modelling when fear is originally acquired via negative verbal information. Research has yet to explore whether fear reduction pathways are also important for fears acquired via vicarious learning. To test this, an experiment compared the effectiveness of positive verbal information and positive vicarious learning interventions for reducing vicariously acquired fears in children (7–9 years). Both vicarious and informational fear reduction interventions were found to be equally effective at reducing vicariously acquired fears, suggesting that acquisition and intervention pathways do not need to match for successful fear reduction. This has significant implications for parents and those working with children because it suggests that providing children with positive information or positive vicarious learning immediately after a negative modelling event may prevent more serious fears developing.     

Who's afraid of the big bad wolf: a prospective paradigm to test Rachman's indirect pathways in children.

Rachman's theory [The conditioning theory of fear insition: a critical examination. Behav. Res. Ther. 15 (1977) 375-387] of fear acquisition suggests that fears and phobias can be acquired through three pathways: direct conditioning, vicarious learning and information/instruction. Although retrospective studies have provided some evidence for these pathways in the development of phobias during childhood [see King, Gullone, & Ollendick, Etiology of childhood phobias: current status of Rachman's three pathway's theory. Behav. Res. Ther. 36 (1998) 297-309 for a review], these studies have relied on long-term past memories of adult phobics or their parents. The current study was aimed towards developing a paradigm in which the plausibility of Rachman's indirect pathways could be investigated prospectively. In Experiment 1, children aged between 7 and 9 were presented with two types of information about novel stimuli (two monsters): video information and verbal information in the form of a story. Fear-related beliefs about the monsters changed significantly as a result of verbal information but not video information. Having established an operational paradigm, Experiment 2 looked at whether the source of verbal information had an effect on changes in fear-beliefs. Using the same paradigm, information about the monsters was provided by either a teacher, an adult stranger or a peer, or no information was given. Again, verbal information significantly changed fear-beliefs, but only when the information came from an adult. The role of information in the acquisition of fear and maintenance of avoidant behaviour is discussed with reference to modern conditioning theories of fear acquisition.     

The effects of cued UCS rehearsal on the retention of differential 'fear' conditioning: an experimental analogue of the 'worry' process

This study describes a human electrodermal conditioning experiment in which subjects were asked to mentally rehearse the UCS in a period following initial fear conditioning and prior to a test period involving nonreinforced presentations of the CS. Subjects who were asked to rehearse the UCS retained a differential fear CR during subsequent unreinforced presentations of the CS, but control subjects who were asked to rehearse either a nonaversive event or an aversive event unrelated to the UCS failed to retain the differential CR they had acquired during conditioning. These results suggest that rehearsal of the UCS during periods when CS and UCS are absent can aid the persistence of a fear CR in the absence of further pairings of the CS and UCS. It is argued that these effects can be explained in terms of the effect of UCS rehearsal on the strength and evaluation of the UCS representation. It is also suggested that cued UCS rehearsal might provide a useful procedure for understanding clinical incubation effects and for understanding how the 'worry' process contributes to the maintenance and incubation of fear.     

Using pavlovian higher-order conditioning paradigms to investigate the neural substrates of emotional learning and memory

In first-order Pavlovian conditioning, learning is acquired by pairing a conditioned stimulus (CS) with an intrinsically motivating unconditioned stimulus (US; e.g., food or shock). In higher-order Pavlovian conditioning (sensory preconditioning and second-order conditioning), the CS is paired with a stimulus that has motivational value that is acquired rather than intrinsic. This review describes some of the ways higher-order conditioning paradigms can be used to elucidate substrates of learning and memory, primarily focusing on fear conditioning. First-order conditioning, second-order conditioning, and sensory preconditioning allow for the controlled demonstration of three distinct forms of memory, the neural substrates of which can thus be analyzed. Higher-order conditioning phenomena allow one to distinguish more precisely between processes involved in transmission of sensory or motor information and processes involved in the plasticity underlying learning. Finally, higher-order conditioning paradigms may also allow one to distinguish between processes involved in behavioral expression of memory retrieval versus processes involved in memory retrieval itself.     

Origins of childhood fears: an evaluation of Rachman's theory of fear acquisition

This study explored Rachman's (1977) theory of fear acquisition in a large sample of Australian and American children and adolescents. Participants completed a questionnaire that addressed different pathways of fear acquisition for 10 highly prevalent fears. The majority of children attributed the onset of their fears to vicarious and instructional factors, although these indirect sources of fear were often combined with direct conditioning experiences. Also examined were effects for gender, age, and nationality. Boys and preadolescents were found to report more direct and vicarious experiences than girls or adolescents. Effects due to nationality were minimal. Methodological limitations attendant to self-reports were acknowledged.     

How do social fears in adolescence develop? Fear conditioning shapes attention orienting to social threat cues

Social fears emerging in adolescence can have negative effects on emotional well-being. Yet the mechanisms by which these risks occur are unknown. One possibility is that associative learning results in fears to previously neutral social stimuli. Such conditioned responses may alter subsequent processing of social stimuli. We used a novel conditioning task to examine how associative processes influence social fear and attention orienting in adolescents. Neutral photographs were paired with socially rewarding or aversive stimuli during conditioning; a dot-probe task then assessed biases in attention orienting. The social conditioning task modified subjective ratings of the neutral stimuli. Moreover, for the neutral stimulus that was paired with the aversive stimulus, the strength of conditioning showed a relationship with subsequent attentional vigilance. The findings elucidate mechanisms by which negative peer experiences during adolescence may affect emotional processing.     

How do social fears in adolescence develop? Fear conditioning shapes attention orienting to social threat cues

Social fears emerging in adolescence can have negative effects on emotional well-being. Yet the mechanisms by which these risks occur are unknown. One possibility is that associative learning results in fears to previously neutral social stimuli. Such conditioned responses may alter subsequent processing of social stimuli. We used a novel conditioning task to examine how associative processes influence social fear and attention orienting in adolescents. Neutral photographs were paired with socially rewarding or aversive stimuli during conditioning; a dot-probe task then assessed biases in attention orienting. The social conditioning task modified subjective ratings of the neutral stimuli. Moreover, for the neutral stimulus that was paired with the aversive stimulus, the strength of conditioning showed a relationship with subsequent attentional vigilance. The findings elucidate mechanisms by which negative peer experiences during adolescence may affect emotional processing.     

UCS revaluation and conditioning models of acquired fears

Recent developments in the study of Pavlovian conditioning in humans have suggested that the strength of a conditioned response (CR) is affected not only by associative processes that link the conditioned stimulus (CS) with the unconditioned stimulus (UCS), but also by processes which lead the individual to revalue the UCS itself. These latter processes can frequently lead to dramatic changes in CR strength independently of any experience with the CS-UCS contingency. This paper discusses a number of ways in which UCS revaluation can be effected in human subjects, and discusses their implications for conditioning models of acquired fears.     

Genetic and environmental causes of the interrelationships between self-reported fears. A study of a non-clinical sample of Norwegian identical twins and their families

The present study reports results from a study of the self-reported fears of identical twins and their spouses and offspring. Factor analysis with oblique rotation of questionnaire responses yielded four correlated fear dimensions: situational fears, illness-injury fears, social fears, and fear of small animals. Models allowing for genetic and cultural transmission, together with specially correlated environments for twins, were fitted, both for separate fears and across fears. Simple models with only genetic and uncorrelated environments were sufficient to account for each the fear dimensions considered separately. The cross-dimensional analyses revealed a genetic and an environmental factor common to the four fear dimensions, together with fear-specific genetic and environmental factors. The impact of the common genetic and common environmental factor varied across dimensions. No evidence of cultural transmission or specially correlated twin environments of the cross-dimensional environments was detected. It is concluded that both common and fear-specific genes and (individual-specific) common and fear-specific environments are necessary to account for the data. The results are discussed in terms of the prepared learning hypothesis and the expectancy bias hypothesis.     

对条件化恐惧反应的抑制效应:指导性与习惯性情绪调节的作用

为了考察实验室指导性与个体习惯性情绪调控策略对恐惧反应的影响,先使用问卷调查了81名大学生的习惯性重评与抑制水平,随后将被试分为两组,指导其在条件化恐惧习得过程中进行主动的情绪调节或自然观看,24h后进行恐惧的表达测试。结果发现,习惯性抑制水平与恐惧习得及表达水平呈显著负相关,且指导性情绪调节与习惯性抑制均显著降低了恐惧习得及表达水平。这提示指导性与习惯性情绪调节策略均能够削弱应激的伤害以保护个体。     

Origins of fear of dogs in adults and children: the role of conditioning processes and prior familiarity with dogs.

One hundred adults and 30 children completed questionnaires to investigate fear of dogs. Dog fearful adults asked to recall the origins of their fear reported classical conditioning experiences more frequently than vicarious acquisition or informational transmission. Overall, however, there was no difference in the frequency of attacks reported by the fearful and non-fearful groups. Significantly more fearful than non-fearful adults reported little contact with dogs prior to the onset of their fear which suggests that early non-eventful exposure to dogs may prevent a conditioning event from producing a dog phobia. Most adults reported that their fear began in childhood, and dog fear were more frequently reported by children than by adults. In the aggregate, however, dog-fearful adults and children differed in several ways; children were more likely than adults to report having received warnings about dogs, but also to recognize the potential attractiveness of a friendly dog. Unlike dog-fearful children, dog-fearful adults reported many other fears in addition to their fear of dogs. A better understanding of fear of dogs in adults may depend on discovering why some dog-fearful children, but not others, apparently lose their fear of dogs as they become older.     

The Role of Verbal Threat Information in the Development of Childhood Fear. “Beware the Jabberwock!”

Rachman’s (Behaviour Research and Therapy 15:372–387, 1977; Clinical Psychology Review 11:155–173, 1991) three pathways theory proposed that childhood fears not only arise as a consequence of direct learning experiences, but can also be elicited by means of threat information transmission. This review looks at the scientific evidence for this idea, which has accumulated during the past three decades. We review research on the influences of media exposure on children’s fears, retrospective parent and child reports on the role of threat information in fear acquisition, and experimental studies that explored the causal effects of threat information on childhood fears. We also discuss possible mechanisms by which threat information exerts its influence and the processes relevant to understand the role of this type of learning experience in the origins of fear. Finally, implications for the prevention and intervention of childhood fears are briefly explored, and potential leads for future research will be highlighted.     

Switching from approach to withdrawal is easier than vice versa

The preparedness theory of classical conditioning proposed by Seligman (1970, 1971) has been applied extensively over the past 40 years to explain the nature and “source” of human fear and phobias. In this review we examine the formative studies that tested the four defining characteristics of prepared learning with animal fear-relevant stimuli (typically snakes and spiders) and consider claims that fear of social stimuli, such as angry faces, or faces of racial out-group members, may also be acquired utilising the same preferential learning mechanism. Exposition of critical differences between fear learning to animal and social stimuli suggests that a single account cannot adequately explain fear learning with animal and social stimuli. We demonstrate that fear conditioned to social stimuli is less robust than fear conditioned to animal stimuli as it is susceptible to cognitive influence and propose that it may instead reflect on negative stereotypes and social norms. Thus, a theoretical model that can accommodate the influence of both biological and cultural factors is likely to have broader utility in the explanation of fear and avoidance responses than accounts based on a single mechanism.     

Acquisition and severity of driving-related fears

Rachman's theory of fear acquisition proposes that directly-conditioned fears will differ from indirectly-conditioned fears in magnitude and anxiety response patterns, however the theory has received inconsistent empirical support. The aim of the present study was to describe the fear acquisition pathways for a community sample who reported driving-related fears, and to test Rachman's theory of fear acquisition. One hundred and ninety participants completed a questionnaire which assessed a variety of driving-related situations, reactions to motor vehicle accidents (MVAs), and anxiety response patterns. Professional psychological helpseeking and perceived need for treatment for driving-related fears were also assessed. Results failed to support Rachman's predictions. However, it was confirmed that respondents who had been involved in an MVA were more likely to ascribe their fears to a directly-conditioned pathway. The theoretical and methodological implications of the findings are discussed, along with suggestions for assessment of those with driving-related fears.     

The learning theory model of neurosis—A new approach

This paper is concerned with the development of a learning theory model of neurosis which would not be susceptible to the many criticisms which can be made of former models. Two widely favoured models—those of Freud and Skinner—are rejected because they are either non-falsifiable or tautological. The Watson and Mowrer models are rejected because they have been experimentally invalidated. The model here suggested differs from previous ones in several important respects. In the first place, it replaces the classical law of extinction by a more modern version which allows for incubation (enhancement) effects of exposure to CS-only stimuli, as well as for extinction effects. In the second place, the model emphasizes the importance of individual differences, and suggests precise relations between personality and the conditioning of neurotic behaviours. In the third place, the model lays stress on innate fear patterns and ‘preparedness’ as important factors in the genesis of conditioned fear responses. In the fourth place, the concept of ‘pain’ in the classical animal literature, and its use in creating models of neurosis, is supplemented by other concepts (‘frustrative non-reward’, ‘approach-avoidance’ conflict) which are more relevant to human neurosis. In the fifth place, and most important. the notion of ‘traumatic’, single-trial conditioning is abandoned, and a new theory based on incubation is proposed. It is suggested that the new theory is more adequate than previous ones to account for the known facts of human neurosis, and that it suggests novel types of experiment in both the animal and human fields which can be used to test its adequacy.