
98 Virtual Reality: Concepts and Technologies
aspect, Held & Durlach (1992) state that the interfaces, by their restrictive character
(their lack of transparency), can reduce the feeling of presence.
Fourth, the realism factors that have to do with the realism of the environment,
in its perceptual and structural aspects, but also in its semantic aspects (coherence
of experience). Based on this conceptual framework, the authors have prepared two
questionnaires: the presence questionnaire, which directly measures the degree of sen-
sitivity of the subjects to the factors stated above, and the “immersive tendencies’’
questionnaire, which tries to measure ...