The Role of "Interoceptive" Fear Conditioning in the Development of Panic Disorder

More than 20% of the general population experience a panic attack at least once in their lives; however, only a minority goes on to develop panic disorder (PD). Conditioning mechanisms have been proposed to explain this evolution in persons who are susceptible to developing panic disorder upon a "traumatic" panic attack. According to preparedness theory, some cues are more likely to condition than others, namely, those referring to internal, bodily signals of danger. The aim of the present study was to test this theory in a differential conditioning paradigm, making use of scripts referring to different internal, bodily sensations as conditioned stimulus (CS) and inhalation of 35% CO2 as unconditioned stimulus (UCS). Thirty-three healthy volunteers were assigned to three scripts conditions: "suffocation," "neutral," or "urgency." During acquisition, one of two versions of a particular script was always followed by an inhalation of 35% CO2 (CS+) and the other by room air (CS-). Acquisition was followed by a test phase, where only inhalations of room air were administered. In line with our hypothesis, only participants in the suffocation condition exhibited a selective conditioning effect. They were more fearful and showed a significantly higher increase in tidal volume than participants in the two control conditions. Results are discussed with relation to interoceptive conditioning, preparedness, and the possible role of tidal volume in PD

Priming associations between bodily sensations and catastrophic misinterpretations: Specific for panic disorder?

Cognitive models assume that panic disorder is characterised by a tendency to misinterpret benign bodily symptoms (e.g. breathlessness) in a catastrophic fashion (e.g. suffocation). This is a central part of the cognitive model which presents a core focus for treatment. Several studies have supported this hypothesis. These studies have, however, almost always relied on self-report. In addition to susceptibility to biases (e.g. distortions of memory), a limitation of research based on verbal report is its inability to capture the spontaneous/automatic nature that is attributed to these catastrophic interpretations. The present paper reports on two experiments in which a priming procedure was used to test the hypothesis that panic disorder is characterised by spontaneous catastrophic interpretations and whether this effect is 'specific' to panic disorder. In line with predictions from the cognitive model, it was observed in the first experiment that the panic group demonstrated facilitated responses to trials consisting of a 'symptom' prime and a 'catastrophic outcome' target (e.g. breathlessness - suffocate). Similar effects were not observed for an anxious control group and a nonclinical control group, supporting the specificity of this effect. Interestingly, however, significant priming effects were observed for a group of mental health professionals (part of the healthy control group) who had no history of panic disorder. Subsequently, this unexpected observation was explicitly addressed in a second experiment, which confirmed the findings of Experiment 1. Together, these results suggest that associations between mental representations of benign bodily symptoms and catastrophic outcomes might develop as part of professional knowledge and experience, and should not necessarily be viewed as pathogenic. Theoretical and clinical implications are discussed.status: publishe

The Weight of Cognitions in Panic: The Link between Misinterpretations and Panic Attacks

In cognitive theory it is hypothesized that panic attacks are provoked by catastrophic misinterpretations of bodily sensations. The aim of the present study was to investigate the ability of associated word pairs referring to catastrophic thinking (e.g. palpitations-heart attack) in producing panic attacks. Patients with PD (n = 20), patients with mixed anxiety disorders (n = 20), and a healthy control group (n = 30) participated in the present study. To enhance ecological validity we first conducted a stimulus validation experiment. Subsequently, nine suitable panic and neutral word pairs were presented in block to the participants. Anxiety levels were assessed before and after the presentation. PD patients were more anxious when reading these word pairs, compared to neutral word pairs. However, none of the participants experienced a panic attack upon reading the word pairs. From the present results it seems that catastrophic thinking is rather related to the anticipatory anxiety for panic attacks, but not necessarily with the occurrence of the panic attacks themselves

Median values for (e)VAS, PSL and POM(S) for panic group (PG), anxious controls (AC) and healthy controls (HC) in Experiment 1.

<p>eVAS ent = eVAS entrance, Pre = before start experiment, Pos = at the end of experiment.</p

Median level of anxiety on the electronic Visual Analogue Scale.

<p>Panic word pairs for panic group, anxious controls and healthy controls in Experiment 2.</p

Mean values for age, gender, MADRS, SDS, PAS and STAI-T for panic group (PG), anxious controls (AC) and healthy controls (HC) in Experiment 1.

<p>Standard deviations are presented in brackets.</p><p>Note: MADRS = Montgomery-Asberg Depression Scale; SDS = Self-rating Depression Scale; PAS = Panic and Agoraphobia Scale; STAI-T = State Trait Anxiety Inventory-Trait *significant differences between the groups and between experiment 1&2 **; <i>p</i><.05.</p