Session 4 - Use of VR in empirical brain and mind sciences

Common experimental design

Ekman faces

The goal of each study is the best possible external validity. However, most studies in brain and mind sciences take place in a lab, due to the size and bad mobility of the used devices. To reach a better external validity anyway, it is always tried to recreate an as real as possible environment in the lab.

Everyday life → Approximation → Experiment

For example, in past experiments the subjects got confronted with static pictures of other people doing certain facial expressions. Also, the subjects got handed objects or got touched with sticks or robotic arms whilst lying in the MRI scanner. It is even paid attention to inviting subjects on different times of the day into the lab to gain a wider field of moods, awakeness, situations etc.

→ In lab experiments it is not possible (at the moment) to recreate a real environment, but you know everything about the environment and its factors. Also, the devices to measure the bodily activity are as accurate as possible by the technical standards today.

Experiment → Embedded in → Everyday life

Another way to reach that goal, is to use portable body-tracking devices in real life. These are common practice in social sciences and empirical humanities (fieldwork).

→ The environment is real, but the problem here is that you are not able to count in all factors, which could have influenced the gained data from the subjects (e.g. "Was the tracking-device still set up properly?"). Additionally to that, the devices are often not as accurate as the ones in lab (MRI).

Experiments with the help of VR

The Immersion created by virtual reality devices allows us also to emulate the real world. By that, it is possible to bring a subset of the real world to the lab. Therefore we can gain more generalizable data and know about all the circumstances in the environment.

Example

Room 101

An example for such an experiment is Room 101 of the The VR Wunderkammer project by Cade McCall. Here, the subject has to collect glasses with fluids in a room. It starts off with an empty room and a single glass and with every new stage there's added different cirumstances to the room. Such as lava around a small path, boxes or even a moving spider. The picture to the right shows a subject trying to pick a glass from a moving spider's head. The whole session can be watched here. See also [serious_games_in_experiments] for more examples and details about that subject.

This experiment is meant to measure people's anxieties and is therefore also exaggerating with certain parameters (oversized spider, lava), which people usually don't know from the real world.

Limitations

VR takes a huge advantage of being able to move the head in any direction. But exactly that is taken away when it's used in an MRI, since the head has to be hold steady in there. Another problem with the head movement is that a VR-user can't really tilt his head to - let's say - look around a corner, since the gaze is calculated to one steady point at the moment. Also, a simulated realism (as in Room 101) doesn't feel completly real obviously. One reason should be the not-so-advanced graphics yet. To solve that problem, one could try it with photo-realism, but in that case the VR-user mostly can't move all around the virtual environment and has to follow a certain path. The reason here is, that one would need a 360°-3D-view from each point in the real environment. Obviously it is much easier to stick to a simulated or perceived realism then. One of the biggest refutations is here the non-reproducible human facial expressions though. Additionally to that, it is extremely hard to display the user's bodily self.

Summary

• VR has become easily (and inexpensive) available
• Promises to increase external/ecological validity of research findings
• Still has shortcomings:
  • Challenging analysis
  • Bodily self
  • Interaction in VR