Higher scores represent higher positive/negative affect. click this Cronbach’s α is 0.85 for both scales (Krohne et al. 1996). The current sample achieved a Cronbach’s α of 0.79 for the PA subscale and 0.88 for the NA subscale. In addition, the PD group completed the Panik und Agoraphobie
Skala (PAS, Bandelow 1997), which measures severity of PD on four scales Inhibitors,research,lifescience,medical comprising two items (panic attacks, agoraphobic avoidance, constraints in daily life and worry on healthiness), one scale with three items (anticipatory anxiety), plus one additional item to assess whether panic attacks are mostly especially unexpected or related to feared situations. The PAS overall score ranges from 0 to 52 with a cutoff of 9 indicating slight PD. Psychometric properties are overall sound with a test–retest reliability of 0.73, Inhibitors,research,lifescience,medical Cronbach’s α of 0.86 and high convergent validity ranging from 0.58 to 0.76 (Bandelow 1997). Cronbach’s α for the individual subscales ranged
between 0.70 and 0.94 in the current sample. There are reports on associations between performance in the mental heartbeat-tracking task and participant’s gender (Ludwick-Rosenthal and Neufeld 1985) and body mass index Inhibitors,research,lifescience,medical (BMI, Montgomery et al. 1984; Jones et al. 1987), as well as between educational level and IGT performance (Davis et al. 2008). We assessed gender and educational level as control variables Inhibitors,research,lifescience,medical via self-report questionnaires. BMI was assessed at a medical examination during admission. Procedure The study was carried out in compliance with the Code of Ethics of the World Medical Association (Declaration of Helsinki) and was approved by the ethics committee of the Schön Klinik Roseneck. Participants participated voluntarily and received no compensation for taking part in the study. Signed informed consent was obtained Inhibitors,research,lifescience,medical for subjects after the nature of the procedures was explained. Next, participants completed the questionnaires and
subsequently performed the mental-tracking task. After assessment of cardiocepetive accuracy, the participants performed the IGT. Data reduction First, interbeat intervals were extracted from the raw ECG using ARTiiFACT (Kaufmann et al. 2011). Next, for each time interval of Brefeldin_A 25-, 35-, and 45-sec cardioceptive accuracy was calculated with the formula presented in Figure Figure1.1. The result is an index that ranges from 0 to 1, with 1 indicating perfect accuracy of heartbeat detection. Figure 1 Formula for computing the cardioceptive accuracy index across three time intervals (Werner et al. 2009). Statistical analysis All data were checked for normal distribution with Kolmogorov–Smirnov tests and Lilliefors Significance Correction. The various group characteristics were compared using independent sample t-tests. To assess associations of cardioception with IGT parameters and other variables, Pearson’s correlations were computed.