You cover up both the rubber hand and their real hand, and
ask them to just point to where they think their real hand is, or guess sort of.
And if you then do the illusion with synchronous stroking,
hopefully they will feel like the hand's part of their body.
And then you ask them again where they think their hand is.
So if their hand's here, the rubber hand's here.
You'll get a shift in where they think the hand is to
normally some where in the middle.
So this sort of visual signal and
this processing of the rubber hand as part of a body then changes how we perceive our
real hand's location in space in an entirely different sensory modality.
>> Right, so it's really useful in terms of comparing,
to try to understand our relationship with our own body.
And how does that then have implications in our self-confidence,
our self-identity, and all these kind of attitude related,
[INAUDIBLE] higher-level research problems.
>> Yeah, yes, and also lower level things like how are different senses combined and
what senses inform our senses of the ownership.
So we can see how there's vision, tactile sensation.
But there's also stuff like proprioception,
which is changed by the combination vision and tactile perception.
>> Yeah, and I guess why you need this application, I can think about is to then
use to answer we can gather from these kind of experiments to help people with
some kind of neurological disorders to understand what could have gone wrong.
And how do we sort of help them to rehabilitate their abilities.
>> Yes, there's a lot of interest in this work for people who are designing
prosthetics, also artificial limbs for people who've lost them.
>> So as a psychologist, just using kind of physical problems you have,
can you do something else other than rub a hand illusion or
the illusion where we have the ownership illusion of somebody else hand or nose.
Is there any other body part we can let our participant to embody?
>> So it seems like there definitely are.
It seems like actually you could probably do it with pretty much any body part.
And so people have done rubber foot illusions.
>> Of course.
>> Legs, probably the most interesting in terms of my research in social
neuroscience and social cognition is what's called the effacement illusion.
So that's essentially if we were doing it now, we'd sit here and
you have to match up the cheeks.
But we'd have like two paintbrushes or two little Q-tips and
we'd stroke each cheek in symphony.
>> [LAUGH] >> It's not as strong as the rubber hand
illusion.
In that illusion people would normally feel very strongly in this hand's
part of your body.
Because face is a far more distinct and we probably know what our own face looks like
and then identify it from reasoning, we cannot identify our own hands.
>> Interesting, so that's a lot of interesting things going on in psychology
about this embodiment illusion.
And now we have both you and Mel here.
Maybe we can have a little discussion about from your perspective how do
you think VR could kind of help in terms of embodiment illusion?
>> So I think Mel's work has been really important in showing how
far this VR cams would be helpful in looking at body perception.
>> Mm-hm.
>> And embodiments and social factors as well.
I guess one of the big things VR adds is in these traditional illusions you
know you have this rubber and and it sits on the table.
So as soon as a person moves, that's totally broken or pretty broken pretty
quickly, and they will no longer feel that the hand's a part of their body.
Whereas in VR using motion tracking, then you can really get
a much fuller visual motor illusion where the person moves.
And they can see this body in the virtual world, moving in sync with them and
doing what they want it to.
And I think sending those kind of motor signals out there and
motor commands, and having the body respond to generally probably it
creates a stronger illusion and a more adaptable one.
>> Yes, it basically gives you flexibility in the sense that you can
make the virtual body or the virtual body parts do whatever you want.
So you can program them to move with a person, or not move with a person,
to move synchronously, asynchronously.
The person can move their right arm, and the left virtual arm might move.
Many different things there are possible, but
very difficult to do and clumsy to do with physical props.
>> Okay, so we'll talk more about VR and embodiment illusion the rest of the type
of video clips, but for now thanks very much, Harry.
>> Thanks. >> Really nice to see you.
>> Thanks, nice to see you.
>> Thanks, Mel.
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