@article{ReichertsGerdesPaulietal.2016,
  author    = {Reicherts, Philipp and Gerdes, Antje B. M. and Pauli, Paul and Wieser, Matthias J.},
  title     = {Psychological placebo and nocebo effects on pain rely on expectation and previous experience},
  series = {Journal of Pain},
  volume    = {17},
  journal   = {Journal of Pain},
  number    = {2},
  doi       = {10.1016/j.jpain.2015.10.010},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-190962},
  pages     = {203-214},
  year      = {2016},
  abstract  = {Expectation and previous experience are both well established key mediators of placebo and nocebo effects. However, the investigation of their respective contribution to placebo and nocebo responses is rather difficult because most placebo and nocebo manipulations are contaminated by pre-existing treatment expectancies resulting from a learning history of previous medical interventions. To circumvent any resemblance to classical treatments, a purely psychological placebonocebo manipulation was established, namely, the "visual stripe pattern induced modulation of pain." To this end, experience and expectation regarding the effects of different visual cues (stripe patterns) on pain were varied across 3 different groups, with either only placebo instruction (expectation), placebo conditioning (experience), or both (expectation + experience) applied. Only the combined manipulation (expectation + experience) revealed significant behavioral and physiological placebo nocebo effects on pain. Two subsequent experiments, which, in addition to placebo and nocebo cues, included a neutral control condition further showed that especially nocebo responses were more easily induced by this psychological placebo and nocebo manipulation. The results emphasize the great effect of psychological processes on placebo and nocebo effects. Particularly, nocebo effects should be addressed more thoroughly and carefully considered in clinical practice to prevent the accidental induction of side effects.},
  language  = {en}
}
@article{WieserReichertsJuravleetal.2016,
  author    = {Wieser, Matthias J. and Reicherts, Philipp and Juravle, Georgiana and von Leupoldt, Andreas},
  title     = {Attention mechanisms during predictable and unpredictable threat - a steady-state visual evoked potential approach},
  series = {NeuroImage},
  volume    = {139},
  journal   = {NeuroImage},
  doi       = {10.1016/j.neuroimage.2016.06.026},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-187365},
  pages     = {167-175},
  year      = {2016},
  abstract  = {Fear is elicited by imminent threat and leads to phasic fear responses with selective attention, whereas anxiety is characterized by a sustained state of heightened vigilance due to uncertain danger. In the present study, we investigated attention mechanisms in fear and anxiety by adapting the NPU-threat test to measure steady-state visual evoked potentials (ssVEPs). We investigated ssVEPs across no aversive events (N), predictable aversive events (P), and unpredictable aversive events (U), signaled by four-object arrays (30 s). In addition, central cues were presented during all conditions but predictably signaled imminent threat only during the P condition. Importantly, cues and context events were flickered at different frequencies (15 Hz vs. 20 Hz) in order to disentangle respective electrocortical responses. The onset of the context elicited larger electrocortical responses for U compared to P context. Conversely, P cues elicited larger electrocortical responses compared to N cues. Interestingly, during the presence of the P cue, visuocortical processing of the concurrent context was also enhanced. The results support the notion of enhanced initial hypervigilance to unpredictable compared to predictable threat contexts, while predictable cues show electrocortical enhancement of the cues themselves but additionally a boost of context processing.},
  language  = {en}
}