The psychopathological phenomenon of delusions of influence comprises variable disturbances of the self-environment-border leading to the feeling of external influence on thoughts, feelings, impulses or behaviors. Delusions of influence are a hallmark in psychotic illness, but nevertheless, attenuated forms can also appear in healthy individuals. Here we present a newly developed paradigm to induce and assess feelings of external influence during instructed imaginations in healthy individuals. In the current study, we asked 60 healthy individuals to visually imagine different objects. To (...) induce feelings of external influence, we applied one of three different physical setups, and informed the participants whether or not an external influence was attempted during the respective trial. The physical setup as well as the information given to the participants alone were able to modulate the feeling of external influence in all three interventions. The impact of information significantly exceeded the impact of the physical setup on the ratings of experienced external influence. Moreover, the response latency correlated with the estimated feeling of external influence. Additional analyses addressed the influence of the emotional content of imagined objects and examined the intensity and emotional valence of the imaginations. Further supplemental analyses correlated external influence estimation of the participants with other psychopathological measures. In conclusion, this study endorses a quantitative model of psychopathological characteristics, in this case feelings of external influence that can be induced by external cues. (shrink)

The sense of agency is typically defined as the experience of controlling one’s own actions, and through them, changes in the external environment. It is often assumed that this experience is a single, unified construct that can be experimentally manipulated and measured in a variety of ways. In this article, we challenge this assumption. We argue that we should acknowledge four possible agency-related psychological constructs. Having a clear grasp of the possible constructs is important since experimental procedures are only able (...) to target some but not all the possible constructs. The unacknowledged misalignment of the possible constructs of a sense of agency and the experimental procedures is a major theoretical and methodological obstacle to studying the sense of agency. Only if we recognize the nature of this obstacle will we be able to design the experimental paradigms that would enable us to study the responsible computational mechanisms. (shrink)