Fear conditioning in virtual reality contexts: a new tool for the study of anxiety.

BACKGROUND Context conditioning has been suggested to model clinical anxiety, but context, as manipulated in animal models, has not been translated to human studies. A virtual environment might prove to be the ideal tool for innovative experimental paradigms to study explicitly cued fear and contextual anxiety in humans. METHODS Subjects were guided through a virtual environment that consisted of two rooms connected by a street scene. In each of the rooms, a blue and a yellow panel on a wall served as explicit conditioned stimuli (CS). The panels were displayed several times. One of the panels (CS+) was associated with a shock in one of the rooms (shock room). No shock was administered in the other room (safe room). Acoustic startle stimuli were administered in the presence and in the absence of the panels to assess explicit cued conditioning to the CS and context conditioning to the rooms, respectively. RESULTS Startle was potentiated by the CS+ in both rooms, which suggests generalization of fear across contexts. After acquisition, startle was potentiated in the shock room, compared with the safe room, in the absence of the CS+. CONCLUSIONS These results support the future use of virtual reality to design new conditioning experiments to study both fear and anxiety.