Hypotheses and Motivation

Most stud­ies of pres­ence in vir­tu­al real­i­ty have tak­en place in aca­d­e­m­ic lab­o­ra­to­ries sim­i­lar to the ones we have here at UCL. The advan­tage of this is that par­tic­i­pants in the study get almost exact­ly the same expe­ri­ence and thus the exper­i­men­tal con­di­tions are well controlled.

Now that con­sumer vir­tu­al real­i­ty is reach­ing many more users, in the Pres­ence Exper­i­ment for VRJam we are ask­ing whether we can run an exper­i­ment with peo­ple using their own equip­ment. We lose a lot of con­trol over how the per­son expe­ri­ences the sim­u­la­tion, but we poten­tial­ly get access to many more par­tic­i­pants and a broad­er range of participants.

We were also moti­vat­ed to devel­op the app and these pages to intro­duce new vir­tu­al real­i­ty users to some of the con­cepts that might help us under­stand and improve vir­tu­al reality.

Please do not read any fur­ther if you intend to try the application.

If you haven’t been able to try the Pres­ence Exper­i­ment appli­ca­tion, then what the per­son expe­ri­ences is the following:

• The par­tic­i­pant first enters an envi­ron­ment that presents a short ques­tion­naire. This ques­tion­naire cap­tures some basic par­tic­i­pant infor­ma­tion, includ­ing gen­der, games play­ing expe­ri­ence and vir­tu­al real­i­ty experience.
• The par­tic­i­pant enters a bar scene. They are sat in a chair against a table.
• After few sec­onds, there is a per­for­mance by a singer.
• Dur­ing the per­for­mance anoth­er audi­ence mem­ber knocks a table caus­ing an object to fall towards the user.
• There is brief applause as the singer finishes.
• The par­tic­i­pant is then trans­port­ed to anoth­er scene to answer a series of ques­tions about the experience.
• The expe­ri­ence fin­ish­es with a brief sum­ma­ry of the exper­i­ment for the user.

There are eight dif­fer­ent ver­sions of the expe­ri­ence. Each par­tic­i­pant is ran­dom­ly assigned to one of these ver­sions. There are three variables.

Vari­able 1: The user has a self avatar or not.

Vari­able 2: The singer looks at the user or not:

Vari­able 3: We attempt to induce an illu­sion of body own­er­ship by hav­ing the singer ask the user the tap along to the beat and (if they have an avatar) ani­mat­ing the avatar tap­ping along to the beat, or there is no induction.

See also our Mak­ing Of Video on this page.

The exper­i­ment will test four hypotheses:

1. That the user hav­ing a body increas­es presence
2. That the singer fac­ing the user will increase presence
3. That the illu­sion of tap­ping along to the song will increase presence
4. That the tap­ping induc­tion will increase a body own­er­ship illusion

The first two are well estab­lished in the aca­d­e­m­ic lit­er­a­ture on pres­ence through pre­vi­ous exper­i­ments. We aim to show that such results can be repli­cat­ed in this type of exper­i­men­tal set up.

The third and four are more explorato­ry. They are based on the famous rub­ber hand illu­sion first demon­strat­ed by Botvinik and Cohen.  In this illu­sion, a par­tic­i­pant has the illu­sion that a rub­ber hand is part of their own body (see this instruc­tive video). In the orig­i­nal paper, the illu­sion is induced by syn­chro­nous tap­ping on the rub­ber hand and real hand. Slater et al. were the first to show that a sim­i­lar illu­sion could be induced in vir­tu­al real­i­ty, again by syn­chro­nous tap­ping on the vir­tu­al hand and real hand. Yuan and Steed then demon­strat­ed that the tap­ping induc­tion was unnec­es­sary, and that a vir­tu­al real­i­ty with motion tracked hands could induce a sim­i­lar illu­sion: the expla­na­tion being that the user sees the vir­tu­al hand move as their real hand does.

How­ev­er the GearVR does­n’t have a hand track­er. So for this envi­ron­ment we are see­ing if the user can self-induce the illu­sion by tap­ping their hand on their own leg.