Question: what have you found during your research? is there any evidence that our body could in fact be someone else's? Also, what do you think would happen if we stopped using our limbs, would we become disconnected from our body in the way in which we do not feel like its our own? and for those that have lost limbs due to amputation etc. would this explain why they sometimes feel like their body is no longer theirs? such an interesting subject!

Myrto Efstathiou answered on 5 Mar 2021:

Hi Abby! Your questions are amazing and thank you for them!
For your first question I am at the beginning of my research journey which consists of three studies and I am completing the first study which explores our perceptions of bodily sensations in our hands and feet. Have you noticed sensations such as itching or tingling in your hands and feet? I am exploring how those sensations are attended and it appears that we perceive those sensations in a similar way (similar frequency and intensity) across our body. I have two more studies which I plan to launch within this year which will help me answer my questions. For example, in one of the studies I want to explore do you know that this hand and this foot are yours. A common method to answer this question is to manipulate your brain into perceiving a fake object e.g. a rubber hand, as your own. This is called the rubber hand illusion and in this illusion the participant is watching a fake hand getting stroked at the same time your own hand. What happens in your brain is that you start “losing” sense of your own hand, and you “embody” the fake hand as your own because you can see what happens in the fake hand and you can also feel what happens in your own hand as this information matches.
Abour your second question, there are some conditions in which the individual mistakes their own body for someone else’s as result of a brain injury or stroke. For example, in asomatognosia, patients deny that their hand is their own hand, and there are instances in which a patient has tried to throw her own arm in the trash as she thought that this was her husband’s arm. However, by showing the patient that this body part is attached to their own body, the patient can recognise the body part. In a related condition – somatoparaphrenia- even though the patient is presented with evidence that their limbs are part of their body, they still refuse to accept it.
For the final question, I think that if we completely stopped using our limbs we will feel detached from our own body and we will struggle recognising our body. This is because your brain gets signals from your body and the body tells your brain about its position and movements. For your brain and for your body to recognise one another, your brain has an “image” of your body inside it. Then, when you decide that you want to make a movement, your brain sends signals back to the body to tell you what you need to do (e.g. move the right arm) using the “image” of your body. In conditions with problems in moving their limbs such as in spinal cord injury or in amputation, the connection between body and the brain is disrupted. In those cases, the individual feels detached from their own body and they often pinch or touch their legs to reassure themselves that this is their body.
Please let me know if you have more questions and I am really glad that you found this subject interesting!