Although expectancy effects have been described before (e.g. placebo effect), no one ever questioned their specificity. After all, it might be that when people anticipate pain, they form a representation of the approaching event, which could be shared with other aversive experiences, such as the case of disgust. In the present thesis, I examined the nature and specificity of expectancy of pain and disgust in the context of perceptual decisions (Experiments 1 & 2) and higher cognitive (moral) decisions (Experiments 3 & 4). I conducted four experiments to analyze behavioral, physiological and neural measures (using fMRI) from healthy human volunteers, which were all engaged in a new experimental set-up, specifically developed for testing the following experimental questions: (1) to which degree pain and disgust expectations recruit similar/dissociated representations of the upcoming event? (2) to which extent pain and disgust expectations affect high-level decisions, such as those involving morally-questionable behavior?