| Popis: |
Panic attacks (PAs) are unexpected periods of intense fear concomitant with both strong physiological arousal and subjective symptoms (Poonai et al., 2000; Richey, Schmidt, Hofmann, & Timpano, 2010; Leibold et al., 2013; Richey et al., 2010; Wetherell, Crown, Lightman, Miles, Kaye, & Vedhara, 2006). PAs are most commonly associated with panic disorder (PD), but can occur in any mental disorder and about 20% of the general population experience a panic attack at least once in their lives (Kessler, Chiu, Jin, Ruscio, Shear, & Walters, 2006; Cougle, Feldner, Keough, Hawkins, & Fitch, 2010; American Psychiatric Association, 2013). These unexpected, recurrent attacks severely impact patients’ quality of life and lead to immense health care costs to society. It is unclear whether the physiological arousal that occurs during a PA is necessary for the subjective experience of PAs, or whether these physiological symptoms are an epiphenomenon of central processes related to the experience of the emotion. Beta blockers are drugs that inhibit the activation of the (nor)adrenergic system. Several beta blockers are lipophilic, and therefore can pass the blood brain barrier and have an effect on receptors in both the central- and peripheral nervous system. Hydrophilic beta blockers on the other hand, mainly have an effect on the peripheral nervous system. (Cruickshank, Neil-Dwyer, Cameron, & McAnish, 1980). These characteristics make β blockers suitable to study a fundamental, yet unanswered, question about the processes related to an intense emotion like panic: namely, what the relative contributions of central and peripheral processes are to the subjective experience of panic. In this study we aim to compare the effects on the subjective experience of panic of a β blocker that inhibits (nor)adrenergic activity in the peripheral nervous system (PNS), to a β blocker that inhibits (nor)adrenergic activity in both the peripheral- and central nervous system (CNS). |
