Refine
Has Fulltext
- yes (6)
Is part of the Bibliography
- yes (6)
Document Type
- Doctoral Thesis (6)
Language
- English (6)
Keywords
- virtual reality (2)
- virtuelle Realität (2)
- ADHS (1)
- Addiction (1)
- Alpha-Aktivität (1)
- Angst (1)
- Angststörung (1)
- Assoziation (1)
- Assoziatives Gedächtnis (1)
- Aufmerksamkeitsdefizit-Syndrom (1)
Institute
Sonstige beteiligte Institutionen
Fear conditioning is an efficient model of associative learning, which has greatly improved our knowledge of processes underlying the development and maintenance of pathological fear and anxiety. In a differential fear conditioning paradigm, one initially neutral stimulus (NS) is paired with an aversive event (unconditioned stimulus, US), whereas another stimulus does not have any consequences. After a few pairings the NS is associated with the US and consequently becomes a conditioned stimulus (CS+), which elicits a conditioned response (CR).
The formation of explicit knowledge of the CS/US association during conditioning is referred to as contingency awareness. Findings about its role in fear conditioning are ambiguous. The development of a CR without contingency awareness has been shown in delay fear conditioning studies. One speaks of delay conditioning, when the US coterminates with or follows directly on the CS+. In trace conditioning, a temporal gap or “trace interval” lies between CS+ and US. According to existing evidence, trace conditioning is not possible on an implicit level and requires more cognitive resources than delay conditioning.
The associations formed during fear conditioning are not exclusively associations between specific cues and aversive events. Contextual cues form the background milieu of the learning process and play an important role in both acquisition and the extinction of conditioned fear and anxiety. A common limitation in human fear conditioning studies is the lack of ecological validity, especially regarding contextual information. The use of Virtual Reality (VR) is a promising approach for creating a more complex environment which is close to a real life situation.
I conducted three studies to examine cue and contextual fear conditioning with regard to the role of contingency awareness. For this purpose a VR paradigm was created, which allowed for exact manipulation of cues and contexts as well as timing of events. In all three experiments, participants were guided through one or more virtual rooms serving as contexts, in which two different lights served as CS and an electric stimulus as US. Fear potentiated startle (FPS) responses were measured as an indicator of implicit fear conditioning. To test whether participants had developed explicit awareness of the CS-US contingencies, subjective ratings were collected.
The first study was designed as a pilot study to test the VR paradigm as well as the conditioning protocol. Additionally, I was interested in the effect of contingency awareness. Results provided evidence, that eye blink conditioning is possible in the virtual environment and that it does not depend on contingency awareness. Evaluative conditioning, as measured by subjective ratings, was only present in the group of participants who explicitly learned the association between CS and US.
To examine acquisition and extinction of both fear associated cues and contexts, a novel cue-context generalization paradigm was applied in the second study. Besides the interplay of cues and contexts I was again interested in the effect of contingency awareness. Two different virtual offices served as fear and safety context, respectively. During acquisition, the CS+ was always followed by the US in the fear context. In the safety context, none of the lights had any consequences. During extinction, a additional (novel) context was introduced, no US was delivered in any of the contexts. Participants showed enhanced startle responses to the CS+ compared to the CS- in the fear context. Thus, discriminative learning took place regarding both cues and contexts during acquisition. This was confirmed by subjective ratings, although only for participants with explicit contingency awareness. Generalization of fear to the novel context after conditioning did not depend on awareness and was observable only on trend level.
In a third experiment I looked at neuronal correlates involved in extinction of fear memory by means of functional magnetic resonance imaging (fMRI). Of particular interest were differences between extinction of delay and trace fear conditioning. I applied the paradigm tested in the pilot study and additionally manipulated timing of the stimuli: In the delay conditioning group (DCG) the US was administered with offset of one light (CS+), in the trace conditioning group (TCG) the US was presented 4s after CS+ offset. Most importantly, prefrontal activation differed between the two groups. In line with existing evidence, the ventromedial prefrontal cortex (vmPFC) was activated in the DCG. In the TCG I found activation of the dorsolateral prefrontal cortex (dlPFC), which might be associated with modulation of working memory processes necessary for bridging the trace interval and holding information in short term memory.
Taken together, virtual reality proved to be an elegant tool for examining human fear conditioning in complex environments, and especially for manipulating contextual information. Results indicate that explicit knowledge of contingencies is necessary for attitude formation in fear conditioning, but not for a CR on an implicit level as measured by FPS responses. They provide evidence for a two level account of fear conditioning. Discriminative learning was successful regarding both cues and contexts. Imaging results speak for different extinction processes in delay and trace conditioning, hinting that higher working memory contribution is required for trace than for delay conditioning.
In daily life, olfactory stimuli are potential generators of affective states, but also have a strong influence on social interaction. Pleasant odors have been shown to increase perceived attractiveness and pro-social behavior, whereas unpleasant body odors are often associated with negative personality traits. Since both pleasant odors and positive affective state facilitate pro-social behavior, it is conceivable that the influence of the odors on social interaction is mediated by the induced affective state elicited by the odor itself. The present thesis aims at exploring the impact of hedonic, i.e., pleasant or unpleasant, odors on the processing and evaluation of social stimuli as assessed by verbal, physiological, and behavioral indices. First, I investigate the effects of initially neutral odors which gained threatening value through an aversive conditioning procedure on social stimuli (Study 1). Second, I study the influence of naturally hedonic odors on social interaction. Third, this thesis aims at disentangling differences in the effects of an odor attributed to either a social interaction partner or the environment where the social encounter takes place (Study 2, 3, and 4).
In the first study, a context conditioning procedure was applied, during which one out of two long-lasting neutral odors was paired with an unpredictable aversive unconditioned stimulus (US, i.e., white noise). This odor (CTX+) thereby gained threatening value, while another odor (CTX-) remained unpaired and therefore signaled safety. During a test session, facial stimuli were presented within both conditioned olfactory contexts. Results indicate that autonomic arousal was increased to faces when presented in the threatening odor context. Additionally, participants rated facial stimuli as more aversive when presented in the threatening odor as compared to the safety odor, indicating that faces acquire hedonic value from the odor they were presented in. Strikingly, angry facial expressions received additional processing resources when presented within a threatening olfactory context, as reflected on verbal reports and electrodermal activity (EDA). This latter finding suggests that threat-related stimuli, here angry faces, are preferentially processed within an olfactory context where a threat might happen.
Considering that the hedonic value of an odor may be quite subjective, I conducted a pilot study in order to identify odors with pleasant vs. unpleasant properties for most participants. Seven odors (four pleasant and three unpleasant) were rated with respect to their valence (pleasant vs. unpleasant), arousal (arousing vs. calm), and intensity. Additionally, EDA was measured. Two pleasant (Citral and Eucalyptol) and two unpleasant (“Animalis” and Isobutyraldehyde) odors were chosen from the original seven. The unpleasant odors were rated as more negative, arousing, and intense than the positive ones, but no differences were found regarding EDA.
These four odors were subsequently used in a virtual reality (VR) paradigm with two odor attribution groups. Participants of the social attribution group (n = 59) were always passively guided into the same room (an office) towards one out of two virtual agents who were either paired with the pleasant or the unpleasant odor. Participants of the contextual attribution group (n = 58) were guided into one out of two rooms which were either paired with the pleasant or the unpleasant odor and where they always met the same agent. For both groups, the agents smiled, frowned or remained with a neutral facial expression. This design allowed evaluating the influence of odor valence as a within-subjects factor and the influence of odor attribution as a between-subjects factor. Unpleasant odors facilitated the processing of social cues as reflected by increased verbal and physiological arousal as well as reduced active approach behavior. Specific influence of odor valence on emotional facial expressions was found for ratings, EDA, and facial mimicry, with the unpleasant odor causing a levelling effect on the differences between facial expressions. The social attribution group exhibited larger differences between odors than the contextual group with respect to some variables (i.e., ratings and EDA), but not to others (i.e., electrocortical potentials – ERPs – and approach behavior). In sum, unpleasant in comparison to pleasant odors diminished emotional responses during social interaction, while an additional enhancing effect of the social attribution was observed on some variables. Interestingly, the awareness that an interaction partner would smell (pleasantly or unpleasantly) boosted the emotional reactivity towards them.
In Study 3, I adapted the VR paradigm to a within-subjects design, meaning that the different attribution conditions were now manipulated block-wise. Instead of an approach task, participants had to move away from the virtual agent (withdrawal task). Results on the ratings were replicated from Study 2. Specifically, the difference between pleasant and unpleasant odors on valence, arousal, and sympathy ratings was larger in the social as compared to the contextual attribution condition. No effects of odor or attribution were found on EDA, whereas heart rate (HR) showed a stronger acceleration to pleasant odors while participants were passively guided towards the agent. Instead of an approach task, I focused on withdrawal behavior in this study. Interestingly, independently of the attribution condition, participants spent more time withdrawing from virtual agents, when an unpleasant odor was presented. In sum, I demonstrated that the attribution of the odors to the social agent itself had an enhancing effect on their influence on social interaction.
In the fourth and last study, I applied a similar within-subjects protocol as in Study 3 with an additional Ultimatum Game task as a measure of social interaction. Overall findings replicated the results of Study 3 with respect to HR and EDA. Strikingly, participants offered less money to virtual agents in the bad smelling room than in the good smelling room. In contrast to Study 3, no effects of odor attribution were found in Study 4. In sum, again I demonstrated that unpleasant odor may lessen social interaction not only when the interaction partner smells badly, but also in more complex interaction situations.
In conclusion, I demonstrated that hedonic odors in general influence social interaction. Thus, pleasant odors seem to facilitate, while unpleasant odors seem to reduce interpersonal exchanges. Therefore, the present thesis extends the body of literature on the influence of odors on the processing of social stimuli. Although I found a direct influence of odors on social preferences as well as on the physiological and behavioral responses to social stimuli, I did not disentangle impact of odor per se from the impact of the affective state. Interestingly, odor attribution might play an additional role as mediator of social interactions such as odor effects in social interactions might be boosted when the smell is attributed to an individual. However, the results in this regard were less straightforward, and therefore further investigations are needed. Future research should also take into account gender or other inter-individual differences like social anxiety.
Frontal asymmetry, a construct invented by Richard Davidson, linking positive and negative valence as well as approach and withdrawal motivation to lateralized frontal brain activation has been investigated for over thirty years. The frontal activation patterns described as relevant were measured via alpha-band frequency activity (8-13 Hz) as a measurement of deactivation in electroencephalography (EEG) for homologous electrode pairs, especially for the electrode position F4/ F3 to account for the frontal relative lateralized brain activation.
Three different theories about frontal activation patterns linked to motivational states were investigated in two studies. The valence theory of Davidson (1984; 1998a; 1998b) and its extension to the motivational direction theory by Harmon-Jones and Allen (1998) refers to the approach motivation with relative left frontal brain activity (indicated by relative right frontal alpha activity) and to withdrawal motivation with relative right frontal brain activation (indicated by relative left frontal alpha activity). The second theory proposed by Hewig and colleagues (2004; 2005; 2006) integrates the findings of Davidson and Harmon – Jones and Allen with the reinforcement sensitivity theory of Jeffrey A. Gray (1982, 1991). Hewig sees the lateralized frontal approach system and withdrawal system proposed by Davidson as subsystems of the behavioral activation system proposed by Gray and bilateral frontal activation as a biological marker for the behavioral activation system. The third theory investigated in the present studies is the theory from Wacker and colleagues (2003; 2008; 2010) where the frontal asymmetrical brain activation patterns are linked to the revised reinforcement sensitivity theory of Gray and McNaughton (2000). Here, right frontal brain activity (indicated by lower relative right frontal alpha activity) accounts for conflict, behavioral inhibition and activity of the revised behavioral inhibition system, while left frontal brain activation (indicated by lower relative left frontal alpha activity) stands for active behavior and the activity of the revised behavioral activation system as well as the activation of the revised flight fight freezing system. In order to investigate these three theories, a virtual reality T-maze paradigm was introduced to evoke motivational states in the participants, offering the opportunity to measure frontal brain activation patterns via EEG and behavior simultaneously in the first study. In the second study the virtual reality paradigm was additionally compared to mental imagery and a movie paradigm, two well-known state inducing paradigms in the research field of frontal asymmetry.
In the two studies, there was confirming evidence for the theory of Hewig and colleages (2004; 2005; 2006), showing higher bilateral frontal activation for active behavior and lateralized frontal activation patterns for approach (left frontal brain activation) and avoidance (right frontal brain activation) behavior. Additionally a limitation for the capability model of anterior brain asymmetry proposed by Coan and colleagues (2006), where the frontal asymmetry should be dependent on the relevant traits driving the frontal asymmetry pattern if a relevant situation occurs, could be found. As the very intense virtual reality paradigm did not lead to a difference of frontal brain activation patterns compared to the mental imagery paradigm or the movie paradigm for the traits of the participants, the trait dependency of the frontal asymmetry in a relevant situation might not be given, if the intensity of the situation exceeds a certain level. Nevertheless there was an influence of the traits in the virtual reality T-maze paradigm, because the shown behavior in the maze was trait-dependent.
The implications of the findings are multifarious, leading from possible objective personality testing via diversification of the virtual reality paradigm to even clinical implications for depression treatments based on changes in the lateralized frontal brain activation patterns for changes in the motivational aspects, but also for changes in bilateral frontal brain activation when it comes to the drive and preparedness for action in patients. Finally, with the limitation of the capability model, additional variance in the different findings about frontal asymmetry can be explained by taking the intensity of a state manipulation into account.
Attention-Deficit/Hyperactivity Disorder (ADHD) is characterized by symptoms of inattentiveness and hyperactivity/impulsivity. Besides, increasing evidence points to ADHD patients showing emotional dysfunctions and concomitant problems in social life. However, systematic research on emotional dysfunctions in ADHD is still rare, and to date most studies lack conceptual differentiation between emotion processing and emotion regulation. The aim of this thesis was to systematically investigate emotion processing and emotion regulation in adult ADHD in a virtual reality paradigm implementing social interaction. Emotional reactions were assessed on experiential, physiological, and behavioral levels.
Experiment 1 was conducted to develop a virtual penalty kicking paradigm implying social feedback and to test it in a healthy sample. This paradigm should then be applied in ADHD patients later on. Pleasant and unpleasant trials in this paradigm consisted of hits respectively misses and subsequent feedback from a virtual coach. In neutral trials, participants were teleported to different spots of the virtual stadium. Results indicated increased positive affectivity (higher valence and arousal ratings, higher zygomaticus activations, and higher expression rates of positive emotional behavior) in response to pleasant compared to neutral trials. Reactions to unpleasant trials were contradictory, indicating increased levels of both positive and negative affectivity, compared to neutral trials. Unpleasant vs. neutral trials revealed lower valence ratings, higher arousal ratings, higher zygomaticus activations, slightly lower corrugator activations, and higher expression rates of both positive and negative emotional behavior. The intensity of emotional reactions correlated with experienced presence in the virtual reality.
To better understand the impact of hits or misses per se vs. hits or misses with coach feedback healthy participants’ emotional reactions, only 50% of all shots were followed by coach feedback in experiment 2. Neutral trials consisted of shots over the free soccer field which were followed by coach feedback in 50 % of all trials. Shots and feedback evoked more extreme valence and arousal ratings, higher zygomaticus activations, lower corrugator activations, and higher skin conductance responses than shots alone across emotional conditions. Again, results speak for the induction of positive emotions in pleasant trials whereas the induction of negative emotions in unpleasant trials seems ambiguous. Technical improvements of the virtual reality were reflected in higher presence ratings than in experiment 1.
Experiment 3 investigated emotional reactions of adult ADHD patients and healthy controls after emotion processing and response-focused emotion regulation. Participants successively
went through an ostensible online ball-tossing game (cyber ball) inducing negative emotions, and an adapted version of the virtual penalty kicking game. Throughout cyber ball, participants were included or ostracized by two other players in different experimental blocks. Participants were instructed to explicitly show, not regulate, or hide their emotions in different experimental blocks. Results provided some evidence for deficient processing of positive emotions in ADHD. Patients reported slightly lower positive affect than controls during cyber ball, gave lower valence ratings than controls in response to pleasant penalty kicking trials, and showed lower zygomaticus activations than controls especially during penalty kicking. Patients in comparison with controls showed slightly increased processing of unpleasant events during cyber ball (higher ratings of negative affect, especially in response to ostracism), but not during penalty kicking. Patients showed lower baseline skin conductance levels than controls, and impaired skin conductance modulations. Compared to controls, patients showed slight over-expression of positive as well as negative emotional behavior. Emotion regulation analyses revealed no major difficulties of ADHD vs. controls in altering their emotional reactions through deliberate response modulation. Moreover, patients reported to habitually apply adaptive emotion regulation strategies even more frequently than controls. The analyses of genetic high-risk vs. low-risk groups for ADHD across the whole sample revealed similar results as analyses for patients vs. controls for zygomaticus modulations during emotion processing, and for modulations of emotional reactions due to emotion regulation.
To sum up, the virtual penalty kicking paradigm proved to be successful for the induction of positive, but not negative emotions. The importance of presence in virtual reality for the intensity of induced emotions could be replicated. ADHD patients showed impaired processing of primarily positive emotions. Aberrations in negative emotional responding were less clear and need further investigation. Results point to adult ADHD in comparison to healthy controls suffering from baseline deficits in autonomic arousal and deficits in arousal modulation. Deficits of ADHD in the deliberate application of response-focused emotion regulation could not be found.
Abstract
Tobacco addiction is considered as a chronic relapsing disorder, characterized by compul-sive drug seeking and intake. Learning processes are stressed to account for the situational-specific expression of core features of the disorder, e.g., craving for drug, tolerance and ex-cessive consumption. According to incentive theories, smoke conditioned stimuli are hy-pothesized to be appetitive in nature, promoting craving, approach and consummatory be-havior. Commonly, smoking cues are treated as simple excitatory conditioned stimuli formed by a close and reliable overlap with the drug effect. However, the smoking ritual comprises a multitude of stimuli which may give rise to different forms of learning and con-ditioned responses partially opposing each other. Previous research suggests the predictive content and the temporal proximity of smoking stimuli to the drug effect as important de-terminants of cue reactivity. In contrast to stimuli related to the preparatory stage of smok-ing and the start of consumption (BEGIN stimuli), stimuli from the terminal stage of smok-ing (END stimuli) apparently lack high cue reactivity. Several lines of evidence suggest the poor cue properties of terminal stimuli to be related to their signaling of poor smoke availa-bility. Indeed, cue reactivity is commonly decreased when smoking appears to be unavaila-ble. Moreover, the learning literature suggests that stimuli predictive for the non-availability of reward may acquire the capacity to modulate or oppose the responses of ex-citatory conditioned stimuli. Therefore, the aim of the present thesis was to enhance our knowledge of stimulus control in human drug addiction and incentive motivation by running a series of conditioning studies with smoke intake and monetary reward as reinforcer. Sub-jective report and physiological measures of motivational valence and consummatory re-sponse tendencies were used as dependent variables.
The first experiment of this thesis used a differential conditioning paradigm to reveal evi-dence for the conditioning of preparatory and consummatory responses to a CS+ for smok-ing. Neutral pictograms served as CSs and single puffs on a cigarette as US. In line with the predictions of incentive theories, the excitatory CS+ for smoking acquired the ability to evoke an appetitive conditioned response, as indicated by enhanced activity of the M. zy-gomaticus major. Moreover, anticipation of puffing on the cigarette increased the activity of the M. orbicularis oris (lip muscle), indicating the activation of consummatory response tendencies. Finally, the CS+ evoked stronger skin conductance responses, indicative of in-creased autonomic arousal and orienting in preparation for action. In contrast, the rating data were apparently unaffected by the experimental contingency. In sum, the physiological data provide support for the notion that excitatory smoke conditioning gives rise to appeti-tive and consummatory conditioned responses, which may at least partially contribute to the maintenance of tobacco addiction.
The second experiment of this thesis adapted the conditioning protocol of the first study to probe the functional significance of terminal stimuli in the control of addictive behavior. This study manipulated the predictive relationship of BEGIN and END stimuli to smoke rein-forcement to provide further support for the differential reactivity to both stimuli and the retarded (i.e., delayed) conditioning of END stimuli. Overall, the results of the first study of this thesis were conceptually replicated as the association of a BEGIN stimulus with smoke intake resulted in the acquisition of appetitive and consummatory physiological responses. Importantly, the results revealed evidence for a retarded excitatory conditioning of END stimuli. Thus, pairing of an END stimulus with smoke intake failed to produce a conditioned discrimination in terms of motivational valence and autonomic arousal, as indicated by the activity of the M. corrugator supercilii and the skin conductance data. These results provide further support for the notion that END stimuli may be weak cues for smoking. Moreover, in light of the results of the first study of this thesis, the retarded excitatory conditioning of terminal stimuli may be suggestive of an inhibitory response component, which may be re-lated to their signaling of poor smoke availability. In sum, these results add to a growing body of data, which suggest that the expression of cue reactivity may be modulated by the temporal proximity and the availability of the drug effect.
The aim of the third study of this thesis was to provide “proof of concept” for an inhibi-tory conditioning notion of terminal stimuli. In this analog study BEGIN and END stimuli were emulated as discriminative SD and S for monetary reward. During an acquisition phase conditioned inhibition was established to the S predictive of the non-availability of re-ward. Subsequently a retardation test was used to substantiate conditioned inhibition. In this test, excitatory conditioning of the previous S was compared to the excitatory condi-tioning of a novel control stimulus. Importantly, the results revealed evidence for reward conditioned inhibition as indicated by the retarded acquisition of subjective (pleasure and reward expectancy) and physiological (skin conductance and activity of the M. orbicularis oculi) responses. In sum, these results provide support for the notion that stimuli predictive for the non-availability of reward may acquire the capacity to oppose the responses of ex-citatory conditioned stimuli. Thus, future research may benefit from the consideration of inhibitory conditioning processes in drug addiction, which may be of theoretical, methodo-logical and clinical importance.
In sum, the present thesis revealed evidence for 1) an appetitive nature of excitatory condi-tioned smoking cues, 2) the dependency of this learning process on the temporal position of the conditioned stimuli in the intake ritual and 3) the acquisition of conditioned inhibition by a stimulus predictive for the non-availability of reward, as evident in retarded excitatory conditioning. Overall, these studies made a novel contribution to the field of human drug addiction and incentive motivation and provided valuable suggestions for further research.
Biased cognitive processes are very likely involved in the maintenance of fears and anxiety. One of such cognitive processes is the perceived relationship between fear-relevant stimuli and aversive consequences. If this relationship is perceived although objective contingencies have been random, it is called an (a posteriori) illusory correlation. If this relationship is overestimated before objective contingencies are experienced, it is called an (a priori) expectancy bias. Previous investigations showed that fear-relevant illusory correlations exist, but very few is known about how and why this cognitive bias develops. In the present dissertation thesis, a model is proposed based on a review of the literature on fear-relevant illusory correlations. This model describes how psychological factors might have an influence on fear and illusory correlations. Several critical implications of the model were tested in four experiments.
Experiment 1 tested the hypothesis that people do not only overestimate the proportion of aversive consequences (startle sounds) following emotionally negative stimuli (pictures of mutilations) relative to neutral stimuli (pictures of household objects), but also following highly arousing positive stimuli (pictures of erotic scenes), because arousal might be an important determinant of illusory correlations. The result was a significant expectancy bias for negative stimuli and a much smaller expectancy bias for positive stimuli. Unexpectedly, expectancy bias was restricted to women. An a posteriori illusory correlation was not found overall, but only in those participants who perceived the aversive consequences following negative stimuli as particularly aversive.
Experiment 2 tested the same hypothesis as experiment 1 using a paradigm that evoked distinct basic emotions (pictures inducing fear, anger, disgust or happiness). Only negative emotions resulted in illusory correlations with aversive outcomes (startle sounds), especially the emotions of fear and disgust. As in experiment 1, the extent of these illusory correlations was correlated with the perceived aversiveness of aversive outcomes. Moreover, only women overestimated the proportion of aversive outcomes during pictures that evoked fear, anger or disgust.
Experiment 3 used functional Magnetic Resonance Imaging (fMRI) to measure biased brain activity in female spider phobics during an illusory correlation paradigm. Both spider phobics and healthy controls expected more aversive outcomes (painful electrical shocks) following pictures of spiders than following neutral control stimuli (pictures of mushrooms). Spider phobics but not healthy controls overestimated the proportion of aversive outcomes following pictures of spiders in a trial-by-trial memory task. This a posteriori illusory correlation was correlated with enhanced shock aversiveness and activity in primary sensory-motor cortex in phobic participants. Moreover, spider phobics’ brain activity in the left dorsolateral prefrontal cortex was elevated in response to spider images. This activity also predicted the extent of the illusory correlation, which supports the theory that executive and attentional resources play an important role in the maintenance of illusory correlations.
Experiment 4 tested the hypothesis that the enhanced aversiveness of some outcomes would be sufficient to causally induce an illusory correlation. Neutral images (colored geometric figures) were paired with differently aversive outcomes (three startle sounds varying in intensity). Participants developed an illusory correlation between those images, which predicted the most aversive sound and this sound, which means that this association was overestimated relative to the other associations. The extent of the illusory correlation was positively correlated with participants’ self-reported anxiety. The results imply that the previously found relationship between illusory correlations and outcome aversiveness might reflect a causal impact of outcome aversiveness or salience on illusory correlations.
In sum, the conducted experiments indicate that illusory correlations between fear-relevant stimuli and aversive consequences might persist – among other factors - because of an enhanced aversiveness or salience of aversive consequences following feared stimuli. This assumption is based on correlational findings, a neural measure of outcome perception and a causal influence of outcome aversiveness on illusory correlations. Implications of these findings were integrated into a model of fear-relevant illusory correlations and potential implications are discussed. Future investigations should further elucidate the role of executive functions and gender effects. Moreover, the trial-by-trial assessment of illusory correlations is recommended to increase reliability of the concept. From a clinical perspective, the down-regulation of aversive experiences and the allocation of attention to non-aversive experiences might help to cure anxiety and cognitive bias.