In regards to the former research about anticipatory anxiety, I suggest reading [this](https://www.sciencedirect.com/topics/psychology/anticipatory-anxiety): Conditioning: "The central paradigm to study fear or anxiety generation via conscious evaluative processes is ‘instructed fear’, often also termed ‘anticipatory anxiety’ or ‘threat of shock’. In instructed fear experiments, subjects are told that a defined cue (the ‘conditioned stimulus’ or CS in Pavlovian language) might be or will be followed within a certain time window by a harmful event such as a painful electric shock (the outcome or ‘unconditioned’ stimulus, US). In the purest form of instructed fear paradigms, the cue is never actually followed by the outcome, depriving subjects of learning the cue-outcome contingency through experience, as would be the case in Pavlovian conditioning. Yet, subjects typically show clear fear/anxiety reactions that can be measured through self-report, increases in [skin conductance](https://www.sciencedirect.com/topics/psychology/skin-conductance), heart rate or in the startle reflex response (e.g., Cook and Harris, 1937; Funayama et al., 2001; Holtz et al., 2012; Maier et al., 2012; Phelps et al., 2001). In these cases, the conscious knowledge of the cue-outcome contingency and the associated negative appraisal processes are the only plausible sources of the threat response. It has been argued that such learning via instructions is one of the major routes by which fear develops in humans (Olsson and Phelps, 2004)."