[Last month, I volunteered for a study at the department of neuroscience at Karolinska Institute, if just out of curiosity to see the place. Eventually it didn't work out with my participation, but I got to meet Zakaryah, a student at the Institute, who kindly agreed to tell us a little about his work there. I certainly learned some new vocabulary. Enjoy!]
I read that you are looking for volunteers for a project. Can you tell us what this is all about?
Yes. The project that I am currently involved in is one in the field of cognitive neuroscience. It is part of the research conducted in the lab of Dr. Henrik Ehrsson at the Department of neuroscience, Karolinska Institute. In this project we use an established perceptual illusion called ‘the body swap illusion’ (Petkova & Ehrsson, 2008) in which healthy participants experience the body of a shop mannequin as their own body to understand the behavioral and neural mechanisms underlying the self-attribution of a whole body to oneself. In particular, we are interested in understanding the neural mechanisms underlying the unitary experience of owning an entire body rather than a set of fragmented body parts. My project will contribute important behavioral and physiological data in support of a neuroimaging study conducted by my direct supervisor PhD-candidate Valeria Petkova.
In my experiment the participants wear head-mounted virtual reality displays, through which they see the mannequin’s body. They then receive simultaneous visual and tactile stimulations of various body parts and fill out a questionnaire regarding their experience. Alternatively they might see a knife approaching the mannequin, in which case the sweating of their palms, the so called galvanic skin response, which is a measurement of the sympathetic nervous systems response to dangerous stimuli is measured via electrodes attached to the fingers of the participant. Since the knife is approaching the mannequin and not the body of the participant, the sweating of the palm is used as an objective measurement of the perception of the body ownership illusion.
What is that sort of research good for?
Understanding the perceptual and neural mechanism involved in how we perceive our own body might be useful in the development of neuroprosthetics. Further, understanding the mechanism underlying the healthy perception of body ownership can help develop diagnostic and therapeutic tools in the treatment of pathological disturbances of the bodily self perception in different groups of patients (i.e. stroke, paraplegia, schizophrenia, anorexia etc.). Finally, the results of this type of research are beneficial for some industrial applications, for example in the field of virtual reality, telerobotics or telepresence.
What future studies would you like to do?
I would probably want to investigate more exactly which areas of the brain are involved in producing this feeling of body ownership and various ways to manipulate this. In particular, it would be interesting to see if one could affect this illusion pharmacologically, and how the illusion is correlated to the features of the subjects, because interestingly, not everyone experience this illusion.
What are the presently most pressing open questions in the field?
Here are some examples:
- What are the exact characteristics (i.e. type, receptive field etc) of the neuronal population involved in the neural computation of body ownership?
-What is the exact role of each node in the neural network indentified to be associated with the sense of owning a body. With other words what is the specific role of the ventral premotor cortex, the intraparietal cortex, the putamen, and the cerebellum?
- What is the interplay between body ownership and the sense of agency in the mechanism of self-awareness?
Do you see any relevance for physics or a role for physicists in that kind of research? If so, what?
Of course! Aside from all the technical equipment that is needed to perform these studies, e.g. MRI-scanners, galvanic skin electrodes etc., this research brings up a lot of fundamental questions about how we perceive ourselves and our surroundings, how we make decisions, how effects on different scales interplay, and I believe physics can contribute a lot to those discussions.
For somebody interested in this research, what further reading can you recommend?
One could read some scientific articles about it, however those can be hard to understand if you do not have a background in medicine or neuroscience. I would recommend those who are interested to read bookchapters about this kind of research, which exist in most of the new books in cognitive neuroscience, for example this.
If I'm in Stockholm and interested volunteering for your or similar research, how do I get in contact?
If you are in Stockholm and interested in participating, the best thing to do would probably be to send me an email, my email-adress is: zakaryah.abdulkarim[at]stud.ki.se. The requirements differ depending on the study, but usually there is some experiment in our lab that one can participate in.
Zakaryah is a medical student at Karolinska Institute. In his free time, when he isn’t at Alba Nova taking some evening course that is, he likes exercising, hanging out with friends, and enjoying what the vegetarian cuisine has to offer.