https://www.selleckchem.com/products/curzerene.html a strategy to improve the adherence to self-care behaviours. The ultimate goal of pain research is to provide effective routes for pain relief. Nevertheless, the perception pain relief as a change in pain intensity and un-/pleasantness has only been rarely investigated. It has been demonstrated that pain relief has rewarding and reinforcing properties, but it remains unknown whether the perception of pain relief changes when pain reductions occur repeatedly. Further, it remains an open question whether the perception of pain relief depends on the controllability of the preceding pain. In this study, healthy volunteers (N=38) received five cycles of painful heat stimulation and reduction of this stimulation to a non-painful warm stimulation once in a condition with control of the stimulation and once without control. Participants rated perceived intensity and un-/pleasantness on visual analogue scales during the heat stimulation and immediately after its reduction. Results showed that perceived pain relief, estimated by the difference in ratings during ongoing hea to be considered to maximize the effects of pain relief as a rewarding and reinforcing stimulus. When in pain, pain relief can become an all-dominate goal. The perception of such pain relief can vary depending on external and internal characteristics and thus modulate, e.g., requests for pain killers in clinical settings. Here, we show that perceived intensity and pleasantness of pain relief changes with repetitions and whether the preceding pain is perceived as uncontrollable. Such mechanistic knowledge needs to be considered to maximize the effects of pain relief as a rewarding and reinforcing stimulus.A population-representative sample of young adolescents (N = 2,104, mean age 12.4) reported on digital technology use and relationships in 2015. A subsample (N = 388) completed a 14-day ecological momentary assessment in 2016-2017 via mobile phone. Across