Pauline Dibbets - Academia.edu (original) (raw)
Papers by Pauline Dibbets
Journal of Social Sciences
Problem statement: Research has shown that both positive and negative information can alter a neu... more Problem statement: Research has shown that both positive and negative information can alter a neutral attitude towards an unknown person, with negative information having, in general, a larger impact. Though this positive-negative asymmetry has received considerable attention, it has, to our knowledge, not been tested in more current and powerful social media, such as youtube. Although attitudes are not fixed, literature on the reversal of a recently established attitude by providing counterattitudinal information is sparse. Therefore, the main aims of the present study were to examine positve-negative asymmetry in attitude formation using youtube fragments and to test the permanence of the establihed attitude by providing counter-attitudinal information. Approach: A total of 89 persons received either a positively (P) or a negatively (N) valued youtube fragment concerning a neutral target person. Subsequently, half of each group received positive written information (groups PP and NP) regarding the target person; the other half received negative written information (groups PN and NN). Results: The results indicate that it is indeed possible to change a neutral attitude using youtube fragments, with a larger attitude change after negative than positive material. Textual information reversed this attitude, with an equal effect for positive and negative information. Conclusion/Recommendations: It is possible to quickly change an attitude towards a neutral person using youtube fragments, this formed attitude can easily be reversed by providing textual counterattitudinal information. These findings can contribute to gaining a better understanding of the effect of modern social media on attitude formation and its transiency.
Journal of Behavior Therapy and Experimental Psychiatry
Legal and Criminological Psychology
Purpose. In order to effectively feign post-traumatic stress disorder, a person needs to confabul... more Purpose. In order to effectively feign post-traumatic stress disorder, a person needs to confabulate an exposure narrative and to fabricate symptoms of high distress. The Verifiability Approach (VA) is a lie-detection method based on the notion that truth tellers' narratives include more verifiable (checkable) information than liars' narratives. The Self-Report Symptom Inventory (SRSI) is a measure of over-reporting, and it includes genuine symptoms and pseudosymptoms that are likely to be endorsed in fabricated symptom reports. In this study, we examined whether the VA can help discriminate the fabricated exposure narratives, and whether the SRSI can aid screening for symptom over-reporting. Method. One group of participants (truth tellers) witnessed a vehicle crash scene using the Virtual Reality paradigm (n = 22), while the other group (feigners) was instructed to fabricate such an experience (n = 46). All the participants wrote the exposure narratives and completed the SRSI. Results. Feigners produced non-verifiable (vague) and lengthier narratives than truth tellers, who reported a higher proportion of checkable information. Regarding the symptom reports, feigners endorsed more of trauma-related genuine symptoms and pseudosymptoms than truth tellers. Conclusion. The non-verifiable details and the proportion of verifiable details, together with the SRSI subscales, can assist explaining the reporting strategies of those feigning negative exposures. Post-traumatic stress disorder (PTSD) was officially introduced in 1980 (DSM-3; American Psychiatric Association, 1980) and pertains to a broad range of psychological disturbances as a consequence of a trauma experience (Resnick, West, & Payne, 2008). Originally, this type of diagnosis was associated with war veterans (Adamou & Hale, 2003), but it soon became clear that combat exposure is not the only possible trigger for PTSD. In fact, any negative life event can be experienced as traumatic (
Journal of Behavior Therapy and Experimental Psychiatry
Scandinavian Journal of Pain
Background and aims Interpreting pain- and illness-related stimuli as health-threatening is commo... more Background and aims Interpreting pain- and illness-related stimuli as health-threatening is common among chronic pain patients but also occurs in the general population. As interpretation bias (IB) may affect pain perception and might even play part in the development and maintenance of chronic pain, it is important to improve our understanding of this concept. Several studies suggest an association between IB and pain-related anxiety. However, those studies often rely on verbal and pictorial IB tasks that do not entail a threat of actual pain, therefore lacking personal relevance for healthy participants. The current study investigated whether healthy individuals show an IB towards ambiguous health-related stimuli in a context of actual pain threat, and explored whether this bias is associated to pain anxiety constructs. Methods Thirty-six healthy participants were conditioned to expect painful electrocutaneous shocks (unconditioned stimulus – US) after health-threat words (CS+) bu...
Journal of behavior therapy and experimental psychiatry, 2018
It is assumed that fear responses can be altered by changing the contingency between a conditione... more It is assumed that fear responses can be altered by changing the contingency between a conditioned stimulus (CS) and an unconditioned stimulus (US), or by devaluing the present mental representation of the US. The aim of the present study was to compare the efficacy of contingency- and devaluation-based intervention techniques on the diminishment in - and return of fear. We hypothesized that extinction (EXT, contingency-based) would outperform devaluation-based techniques regarding contingency measures, but that devaluation-based techniques would be most effective in reducing the mental representation of the US. Additionally, we expected that incorporations of the US during devaluation would result in less reinstatement of the US averseness. Healthy participants received a fear conditioning paradigm followed by one of three interventions: extinction (EXT, contingency-based), imagery rescripting (ImRs, devaluation-based) or eye movement desensitization and reprocessing (EMDR, devalua...
Journal of behavior therapy and experimental psychiatry, 2017
The aim of the present study was to replicate our previous study and to further examine the relat... more The aim of the present study was to replicate our previous study and to further examine the relation between fear and positive and negative confirmation bias in children. Fifty-three non-clinical children (9-13 years) were shown pictures of a kindly-perceived (quokka) and a dangerous-looking (aye aye) animal. For each animal, levels of fear and information seeking patterns were obtained. The results indicated that the aye aye was rated as more threatening and less kind than the quokka. For the aye aye more negative than neutral or positive information was selected; no differences were observed for the quokka. Regardless of type of animal, higher fear levels coincided with more search for negative information. Positive confirmation bias in the quokka was indirectly observed as low fear levels were associated with an increased search for positive information. Finally, for the quokka searching negative information coincided with an increase in the scariness of the quokka; this pattern ...
Journal of child and family studies, 2017
This study examined relationships between the self-conscious emotions of guilt and shame in both ... more This study examined relationships between the self-conscious emotions of guilt and shame in both clinical (N = 104) and non-clinical (N = 477) (young) adolescents aged 11-18 years, who completed a questionnaire to assess perceived parental rearing behaviors (EMBU-C) and a scenario-based instrument to measure proneness to guilt and shame (SCEMAS). Results indicated that parental rearing dimensions were positively related to self-conscious emotions. Regarding the non-clinical sample, both favourable (emotional warmth) and unfavourable (rejection) paternal and maternal rearing dimensions were significant correlates of guilt- and shame-proneness. The results for the clinical sample were less conclusive: only maternal emotional warmth and rejection were found to be significantly associated with guilt and shame. Interestingly, no associations between any of the paternal rearing dimensions and self-conscious emotions emerged. Taken together, these results are in keeping with the notion tha...
Behaviour Research and Therapy, Sep 30, 2008
In the present study, it was investigated by employing a human fear conditioning paradigm whether... more 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.
Child psychiatry and human development, Feb 10, 2016
The present cross-sectional study explored the relations between fear-enhancing parenting behavio... more The present cross-sectional study explored the relations between fear-enhancing parenting behaviors (modeling and threat information transmission) and children's cognitive biases and anxiety symptoms. Participants were 258 children aged 7-12 years (132 boys and 126 girls), and their mothers (n = 199) and/or fathers (n = 117). Children and parents completed the Parental Enhancement of Anxious Cognitions questionnaire, which measures parental modeling and threat information transmission, while children also filled in a scale for assessing anxiety symptoms. In addition, children conducted a number of computerized tasks for measuring confirmation and interpretation bias. The data indicated that both biases mediated the relationship between threat information transmission (of both parents) and children's anxiety symptoms. Only interpretation bias significantly mediated the relationship between modeling (of mothers) and anxiety symptoms. These findings give partial support for the...
Journal of Experimental Psychopathology, Oct 16, 2013
ABSTRACT Return of fear following exposure treatment may be explained by ABA-renewal: fear acquir... more ABSTRACT Return of fear following exposure treatment may be explained by ABA-renewal: fear acquired in context A, and extinguished in context B, may return in context A. Conditioning theory predicts that intensity of conditioned fear is mediated by the mental representation of the unconditioned stimulus (US) evoked by the conditioned stimulus (CS). This study tested whether US-devaluation via a dual-task – imagining the US while making eye movements – attenuates fear renewal. Participants acquired fear in context A, and underwent extinction in context A or B. Next, two groups did a filler task (AAA; ABA), one a dual-task of US imagination with eye movements (ABA-DT), and one merely imagined the US (ABA-RO). Finally, participants were re-presented the CSs in context A. ABA-renewal was found for US-expectancy. Dual-tasking, but not recall only, reduced fear renewal. No between-group differences were observed in reductions of vividness, emotionality, and startle responses to the US. Findings suggest that dual-tasking may attenuate fear renewal.
Journal of Systems Integration, 2015
In this paper we introduce the Frequency Ratio (FR) method for dealing with missing values within... more In this paper we introduce the Frequency Ratio (FR) method for dealing with missing values within nearest neighbour search. We test the FR method on known medical datasets from the UCI machine learning repository. We compare the accuracy of the FR method with five commonly used methods (three "imputation" and two "bypassing" methods) for dealing with values that are "missing completely at random" (MCAR) for the purpose of classification. We discovered that in most cases, the FR method outperforms the other methods. We conclude that the FR method is a strong addition to the commonly used methods for dealing with missing values within the nearest neighbour method.
Frontiers in Psychology
Formal theories have linked pathological anxiety to a failure in fear response inhibition. Previo... more Formal theories have linked pathological anxiety to a failure in fear response inhibition. Previously, we showed that aberrant response inhibition is not restricted to anxiety patients, but can also be observed in anxiety-prone adults. However, less is known about the influence of currently experienced levels of anxiety on inhibitory learning. The topic is highly important as state anxiety has a debilitating effect on cognition, emotion, and physiology and is linked to several anxiety disorders. In the present study, healthy female volunteers performed a fear conditioning task, after being informed that they will have to perform the Trier Social Stress Test task (n = 25; experimental group) or a control task (n = 25; control group) upon completion of the conditioning task. The results showed that higher levels of state anxiety corresponded with a reduced discrimination between a stimulus (CS+) typically followed by an aversive event and a stimulus (CS−) that is never followed by an aversive event both during the acquisition and the extinction phase. No effect of state anxiety on the skin conductance response associated with CS+ and CS− was found. Additionally, higher levels of state anxiety coincided with more negative valence ratings of the CSs. The results suggest that increased stress-induced state anxiety might lead to stimulus generalization during fear acquisition, thereby impairing associative learning.
Frontiers in psychology, 2015
Most people are exposed to a violent or life-threatening situation during their lives, but only a... more Most people are exposed to a violent or life-threatening situation during their lives, but only a minority develops post-traumatic stress disorder (PTSD). Experimental studies are necessary to assess risk factors, such as imagery ability, for the development of PTSD. Up to now the trauma film paradigm (TFP) has functioned as an analogue for PTSD. This paradigm is known to induce involuntary intrusions, a core symptom of PTSD. Though useful, the film paradigm has a drawback, the participant remains an "outsider" and does not immerse in the film scenes. The aim of the present study was to develop a fitting virtual reality (VR) analogue for PTSD and to assess risk factors for the development of PTSD-symptoms, such as intrusions. To this end a novel VR paradigm was compared to the traditional TFP. Both the VR and TFP elicited a negative mood and induction-related intrusions. More immersion was observed in the VR paradigm compared to the TFP. The results of the risk factors wer...
Memory, 2015
During imagery rescripting (ImRs) an aversive memory is relived and transformed to have a more po... more During imagery rescripting (ImRs) an aversive memory is relived and transformed to have a more positive outcome. ImRs is frequently applied in psychological treatment and is known to reduce intrusions and distress of the memory. However, little is known about the necessity to incorporate the central aversive parts of the memory in ImRs. To examine this necessity one hundred participants watched an aversive film and were subsequently randomly assigned to one of four experimental conditions: ImRs including the aversive scenes (Late ImRs), ImRs without the aversive scenes (Early ImRs), imaginal exposure (IE) or a control condition (Cont). Participants in the IE intervention reported the highest distress levels during the intervention; Cont resulted in the lowest levels of self-reported distress. For the intrusion frequency, only the late ImRs resulted in fewer intrusions compared to the Cont condition; Early ImRs produced significantly more intrusions than the Late ImRs or IE condition. Finally, the intrusions of the Late ImRs condition were reported as less vivid compared to the other conditions. To conclude, it seems beneficial including aversive scenes in ImRs after an analogue trauma induction.
Child psychiatry and human development, Jan 6, 2014
The purpose of this study was to examine confirmation bias in children without explicitly inducin... more The purpose of this study was to examine confirmation bias in children without explicitly inducing fear. Eighty non-clinical children (7-13 years) were shown pictures of a neutral animal (quokka) and two dangerous-looking animals (aye aye and possum). For each animal, levels of perceived fear, threat and request for additional threatening or non-threatening information were obtained. A behavioral approach test (BAT) was included as behavioral measure of fear. The results indicated that the aye aye and possum were rated as more threatening and fearful than the quokka. For the aye aye and possum higher fear levels coincided with search for more threatening than non-threatening information. This pattern was absent in non-fearful children and for the non-threatening quokka. During the BAT the quokka was more often approached first compared to the aye aye and possum. Our findings suggest that confirmation bias in children can be observed without using verbal fear induction.
Journal of Experimental Psychopathology, 2013
Return of fear following exposure treatment may be explained by ABA-renewal: fear acquired in con... more Return of fear following exposure treatment may be explained by ABA-renewal: fear acquired in context A, and extinguished in context B, may return in context A. Conditioning theory predicts that intensity of conditioned fear is mediated by the mental representation of the unconditioned stimulus (US) evoked by the conditioned stimulus (CS). This study tested whether US-devaluation via a dual-task -imagining the US while making eye movementsattenuates fear renewal. Participants acquired fear in context A, and underwent extinction in context A or B. Next, two groups did a filler task (AAA; ABA), one a dual-task of US imagination with eye movements (ABA-DT), and one merely imagined the US (ABA-RO). Finally, participants were re-presented the CSs in context A. ABA-renewal was found for US-expectancy. Dual-tasking, but not recall only, reduced fear renewal. No between-group differences were observed in reductions of vividness, emotionality, and startle responses to the US. Findings suggest that dual-tasking may attenuate fear renewal.
Journal of Social Sciences
Problem statement: Research has shown that both positive and negative information can alter a neu... more Problem statement: Research has shown that both positive and negative information can alter a neutral attitude towards an unknown person, with negative information having, in general, a larger impact. Though this positive-negative asymmetry has received considerable attention, it has, to our knowledge, not been tested in more current and powerful social media, such as youtube. Although attitudes are not fixed, literature on the reversal of a recently established attitude by providing counterattitudinal information is sparse. Therefore, the main aims of the present study were to examine positve-negative asymmetry in attitude formation using youtube fragments and to test the permanence of the establihed attitude by providing counter-attitudinal information. Approach: A total of 89 persons received either a positively (P) or a negatively (N) valued youtube fragment concerning a neutral target person. Subsequently, half of each group received positive written information (groups PP and NP) regarding the target person; the other half received negative written information (groups PN and NN). Results: The results indicate that it is indeed possible to change a neutral attitude using youtube fragments, with a larger attitude change after negative than positive material. Textual information reversed this attitude, with an equal effect for positive and negative information. Conclusion/Recommendations: It is possible to quickly change an attitude towards a neutral person using youtube fragments, this formed attitude can easily be reversed by providing textual counterattitudinal information. These findings can contribute to gaining a better understanding of the effect of modern social media on attitude formation and its transiency.
Journal of Behavior Therapy and Experimental Psychiatry
Legal and Criminological Psychology
Purpose. In order to effectively feign post-traumatic stress disorder, a person needs to confabul... more Purpose. In order to effectively feign post-traumatic stress disorder, a person needs to confabulate an exposure narrative and to fabricate symptoms of high distress. The Verifiability Approach (VA) is a lie-detection method based on the notion that truth tellers' narratives include more verifiable (checkable) information than liars' narratives. The Self-Report Symptom Inventory (SRSI) is a measure of over-reporting, and it includes genuine symptoms and pseudosymptoms that are likely to be endorsed in fabricated symptom reports. In this study, we examined whether the VA can help discriminate the fabricated exposure narratives, and whether the SRSI can aid screening for symptom over-reporting. Method. One group of participants (truth tellers) witnessed a vehicle crash scene using the Virtual Reality paradigm (n = 22), while the other group (feigners) was instructed to fabricate such an experience (n = 46). All the participants wrote the exposure narratives and completed the SRSI. Results. Feigners produced non-verifiable (vague) and lengthier narratives than truth tellers, who reported a higher proportion of checkable information. Regarding the symptom reports, feigners endorsed more of trauma-related genuine symptoms and pseudosymptoms than truth tellers. Conclusion. The non-verifiable details and the proportion of verifiable details, together with the SRSI subscales, can assist explaining the reporting strategies of those feigning negative exposures. Post-traumatic stress disorder (PTSD) was officially introduced in 1980 (DSM-3; American Psychiatric Association, 1980) and pertains to a broad range of psychological disturbances as a consequence of a trauma experience (Resnick, West, & Payne, 2008). Originally, this type of diagnosis was associated with war veterans (Adamou & Hale, 2003), but it soon became clear that combat exposure is not the only possible trigger for PTSD. In fact, any negative life event can be experienced as traumatic (
Journal of Behavior Therapy and Experimental Psychiatry
Scandinavian Journal of Pain
Background and aims Interpreting pain- and illness-related stimuli as health-threatening is commo... more Background and aims Interpreting pain- and illness-related stimuli as health-threatening is common among chronic pain patients but also occurs in the general population. As interpretation bias (IB) may affect pain perception and might even play part in the development and maintenance of chronic pain, it is important to improve our understanding of this concept. Several studies suggest an association between IB and pain-related anxiety. However, those studies often rely on verbal and pictorial IB tasks that do not entail a threat of actual pain, therefore lacking personal relevance for healthy participants. The current study investigated whether healthy individuals show an IB towards ambiguous health-related stimuli in a context of actual pain threat, and explored whether this bias is associated to pain anxiety constructs. Methods Thirty-six healthy participants were conditioned to expect painful electrocutaneous shocks (unconditioned stimulus – US) after health-threat words (CS+) bu...
Journal of behavior therapy and experimental psychiatry, 2018
It is assumed that fear responses can be altered by changing the contingency between a conditione... more It is assumed that fear responses can be altered by changing the contingency between a conditioned stimulus (CS) and an unconditioned stimulus (US), or by devaluing the present mental representation of the US. The aim of the present study was to compare the efficacy of contingency- and devaluation-based intervention techniques on the diminishment in - and return of fear. We hypothesized that extinction (EXT, contingency-based) would outperform devaluation-based techniques regarding contingency measures, but that devaluation-based techniques would be most effective in reducing the mental representation of the US. Additionally, we expected that incorporations of the US during devaluation would result in less reinstatement of the US averseness. Healthy participants received a fear conditioning paradigm followed by one of three interventions: extinction (EXT, contingency-based), imagery rescripting (ImRs, devaluation-based) or eye movement desensitization and reprocessing (EMDR, devalua...
Journal of behavior therapy and experimental psychiatry, 2017
The aim of the present study was to replicate our previous study and to further examine the relat... more The aim of the present study was to replicate our previous study and to further examine the relation between fear and positive and negative confirmation bias in children. Fifty-three non-clinical children (9-13 years) were shown pictures of a kindly-perceived (quokka) and a dangerous-looking (aye aye) animal. For each animal, levels of fear and information seeking patterns were obtained. The results indicated that the aye aye was rated as more threatening and less kind than the quokka. For the aye aye more negative than neutral or positive information was selected; no differences were observed for the quokka. Regardless of type of animal, higher fear levels coincided with more search for negative information. Positive confirmation bias in the quokka was indirectly observed as low fear levels were associated with an increased search for positive information. Finally, for the quokka searching negative information coincided with an increase in the scariness of the quokka; this pattern ...
Journal of child and family studies, 2017
This study examined relationships between the self-conscious emotions of guilt and shame in both ... more This study examined relationships between the self-conscious emotions of guilt and shame in both clinical (N = 104) and non-clinical (N = 477) (young) adolescents aged 11-18 years, who completed a questionnaire to assess perceived parental rearing behaviors (EMBU-C) and a scenario-based instrument to measure proneness to guilt and shame (SCEMAS). Results indicated that parental rearing dimensions were positively related to self-conscious emotions. Regarding the non-clinical sample, both favourable (emotional warmth) and unfavourable (rejection) paternal and maternal rearing dimensions were significant correlates of guilt- and shame-proneness. The results for the clinical sample were less conclusive: only maternal emotional warmth and rejection were found to be significantly associated with guilt and shame. Interestingly, no associations between any of the paternal rearing dimensions and self-conscious emotions emerged. Taken together, these results are in keeping with the notion tha...
Behaviour Research and Therapy, Sep 30, 2008
In the present study, it was investigated by employing a human fear conditioning paradigm whether... more 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.
Child psychiatry and human development, Feb 10, 2016
The present cross-sectional study explored the relations between fear-enhancing parenting behavio... more The present cross-sectional study explored the relations between fear-enhancing parenting behaviors (modeling and threat information transmission) and children's cognitive biases and anxiety symptoms. Participants were 258 children aged 7-12 years (132 boys and 126 girls), and their mothers (n = 199) and/or fathers (n = 117). Children and parents completed the Parental Enhancement of Anxious Cognitions questionnaire, which measures parental modeling and threat information transmission, while children also filled in a scale for assessing anxiety symptoms. In addition, children conducted a number of computerized tasks for measuring confirmation and interpretation bias. The data indicated that both biases mediated the relationship between threat information transmission (of both parents) and children's anxiety symptoms. Only interpretation bias significantly mediated the relationship between modeling (of mothers) and anxiety symptoms. These findings give partial support for the...
Journal of Experimental Psychopathology, Oct 16, 2013
ABSTRACT Return of fear following exposure treatment may be explained by ABA-renewal: fear acquir... more ABSTRACT Return of fear following exposure treatment may be explained by ABA-renewal: fear acquired in context A, and extinguished in context B, may return in context A. Conditioning theory predicts that intensity of conditioned fear is mediated by the mental representation of the unconditioned stimulus (US) evoked by the conditioned stimulus (CS). This study tested whether US-devaluation via a dual-task – imagining the US while making eye movements – attenuates fear renewal. Participants acquired fear in context A, and underwent extinction in context A or B. Next, two groups did a filler task (AAA; ABA), one a dual-task of US imagination with eye movements (ABA-DT), and one merely imagined the US (ABA-RO). Finally, participants were re-presented the CSs in context A. ABA-renewal was found for US-expectancy. Dual-tasking, but not recall only, reduced fear renewal. No between-group differences were observed in reductions of vividness, emotionality, and startle responses to the US. Findings suggest that dual-tasking may attenuate fear renewal.
Journal of Systems Integration, 2015
In this paper we introduce the Frequency Ratio (FR) method for dealing with missing values within... more In this paper we introduce the Frequency Ratio (FR) method for dealing with missing values within nearest neighbour search. We test the FR method on known medical datasets from the UCI machine learning repository. We compare the accuracy of the FR method with five commonly used methods (three "imputation" and two "bypassing" methods) for dealing with values that are "missing completely at random" (MCAR) for the purpose of classification. We discovered that in most cases, the FR method outperforms the other methods. We conclude that the FR method is a strong addition to the commonly used methods for dealing with missing values within the nearest neighbour method.
Frontiers in Psychology
Formal theories have linked pathological anxiety to a failure in fear response inhibition. Previo... more Formal theories have linked pathological anxiety to a failure in fear response inhibition. Previously, we showed that aberrant response inhibition is not restricted to anxiety patients, but can also be observed in anxiety-prone adults. However, less is known about the influence of currently experienced levels of anxiety on inhibitory learning. The topic is highly important as state anxiety has a debilitating effect on cognition, emotion, and physiology and is linked to several anxiety disorders. In the present study, healthy female volunteers performed a fear conditioning task, after being informed that they will have to perform the Trier Social Stress Test task (n = 25; experimental group) or a control task (n = 25; control group) upon completion of the conditioning task. The results showed that higher levels of state anxiety corresponded with a reduced discrimination between a stimulus (CS+) typically followed by an aversive event and a stimulus (CS−) that is never followed by an aversive event both during the acquisition and the extinction phase. No effect of state anxiety on the skin conductance response associated with CS+ and CS− was found. Additionally, higher levels of state anxiety coincided with more negative valence ratings of the CSs. The results suggest that increased stress-induced state anxiety might lead to stimulus generalization during fear acquisition, thereby impairing associative learning.
Frontiers in psychology, 2015
Most people are exposed to a violent or life-threatening situation during their lives, but only a... more Most people are exposed to a violent or life-threatening situation during their lives, but only a minority develops post-traumatic stress disorder (PTSD). Experimental studies are necessary to assess risk factors, such as imagery ability, for the development of PTSD. Up to now the trauma film paradigm (TFP) has functioned as an analogue for PTSD. This paradigm is known to induce involuntary intrusions, a core symptom of PTSD. Though useful, the film paradigm has a drawback, the participant remains an "outsider" and does not immerse in the film scenes. The aim of the present study was to develop a fitting virtual reality (VR) analogue for PTSD and to assess risk factors for the development of PTSD-symptoms, such as intrusions. To this end a novel VR paradigm was compared to the traditional TFP. Both the VR and TFP elicited a negative mood and induction-related intrusions. More immersion was observed in the VR paradigm compared to the TFP. The results of the risk factors wer...
Memory, 2015
During imagery rescripting (ImRs) an aversive memory is relived and transformed to have a more po... more During imagery rescripting (ImRs) an aversive memory is relived and transformed to have a more positive outcome. ImRs is frequently applied in psychological treatment and is known to reduce intrusions and distress of the memory. However, little is known about the necessity to incorporate the central aversive parts of the memory in ImRs. To examine this necessity one hundred participants watched an aversive film and were subsequently randomly assigned to one of four experimental conditions: ImRs including the aversive scenes (Late ImRs), ImRs without the aversive scenes (Early ImRs), imaginal exposure (IE) or a control condition (Cont). Participants in the IE intervention reported the highest distress levels during the intervention; Cont resulted in the lowest levels of self-reported distress. For the intrusion frequency, only the late ImRs resulted in fewer intrusions compared to the Cont condition; Early ImRs produced significantly more intrusions than the Late ImRs or IE condition. Finally, the intrusions of the Late ImRs condition were reported as less vivid compared to the other conditions. To conclude, it seems beneficial including aversive scenes in ImRs after an analogue trauma induction.
Child psychiatry and human development, Jan 6, 2014
The purpose of this study was to examine confirmation bias in children without explicitly inducin... more The purpose of this study was to examine confirmation bias in children without explicitly inducing fear. Eighty non-clinical children (7-13 years) were shown pictures of a neutral animal (quokka) and two dangerous-looking animals (aye aye and possum). For each animal, levels of perceived fear, threat and request for additional threatening or non-threatening information were obtained. A behavioral approach test (BAT) was included as behavioral measure of fear. The results indicated that the aye aye and possum were rated as more threatening and fearful than the quokka. For the aye aye and possum higher fear levels coincided with search for more threatening than non-threatening information. This pattern was absent in non-fearful children and for the non-threatening quokka. During the BAT the quokka was more often approached first compared to the aye aye and possum. Our findings suggest that confirmation bias in children can be observed without using verbal fear induction.
Journal of Experimental Psychopathology, 2013
Return of fear following exposure treatment may be explained by ABA-renewal: fear acquired in con... more Return of fear following exposure treatment may be explained by ABA-renewal: fear acquired in context A, and extinguished in context B, may return in context A. Conditioning theory predicts that intensity of conditioned fear is mediated by the mental representation of the unconditioned stimulus (US) evoked by the conditioned stimulus (CS). This study tested whether US-devaluation via a dual-task -imagining the US while making eye movementsattenuates fear renewal. Participants acquired fear in context A, and underwent extinction in context A or B. Next, two groups did a filler task (AAA; ABA), one a dual-task of US imagination with eye movements (ABA-DT), and one merely imagined the US (ABA-RO). Finally, participants were re-presented the CSs in context A. ABA-renewal was found for US-expectancy. Dual-tasking, but not recall only, reduced fear renewal. No between-group differences were observed in reductions of vividness, emotionality, and startle responses to the US. Findings suggest that dual-tasking may attenuate fear renewal.