  During VR demos we have performed over last few years, many participants (in
the absence of any haptic feedback) have commented on their perceived ability
to 'feel' differences between simulated molecular objects. The mechanisms for
such 'feeling' are not entirely clear: observing from outside VR, one can see
that there is nothing physical for participants to 'feel'. Here we outline
exploratory user studies designed to evaluate the extent to which participants
can distinguish quantitative differences in the flexibility of VR-simulated
molecular objects. The results suggest that an individual's capacity to detect
differences in molecular flexibility is enhanced when they can interact with
and manipulate the molecules, as opposed to merely observing the same
interaction. Building on these results, we intend to carry out further studies
investigating humans' ability to sense quantitative properties of VR
simulations without haptic technology.
