Featured Research

from universities, journals, and other organizations

Full body illusion is associated with a drop in skin temperature

Date:
July 30, 2013
Source:
Frontiers
Summary:
Researchers used virtual reality technology with a specialized robotic system to test what happens when the mind is tricked into identifying with another body.

(A) This is a picture of the experimental setup. It shows the participant lying on robotic stroking device. (B) This is the robotic stoking device shown from feet perspective. The top shows the padding removed for motor view and the bottom shows the robot with padding as used in the experiment. (C) This is a schematic representation of the stroking regions (dashed red line), tactile vibrators (blue triangles), and thermocouple placement (green x).
Credit: Roy Salomon et al (2013) Frontiers in Behavioral Neuroscience, CC-BY 3,0

Researchers from the Center for Neuroprosthetics at the Swiss Federal Institute of Technology (EPFL), Switzerland, show that people can be "tricked" into feeling that an image of a human figure -- an "avatar" -- is their own body. The study is published in the open-access journal Frontiers in Behavioral Neuroscience.

Twenty-two volunteers underwent a Full Body Illusion when they were stroked with a robotic device system while they watched an avatar being stroked in the same spot. The study is the first to demonstrate that Full Body Illusions can be accompanied by changes in body temperature.

Participants wore a 3D high-resolution head-mounted display to view the avatar from behind. They were then subjected to 40 seconds of stroking by a robot, on either their left or right back or on their left or right leg. Meanwhile, they were shown a red dot that moved synchronously on the same regions of the avatar (see image).

After the stroking, the participants were prompted to imagine dropping a ball and to signal the moment when they felt that the ball would hit the floor. This allowed the researchers to objectively measure where the participants perceived their body to be.

The volunteers were asked questions about how much they identified with the avatar and where they felt the stroking originated from. Furthermore, to test for physiological changes during the illusion, the participants' skin temperature was measured on four locations on the back and legs across 20 time points.

Results showed that stroking the same body part simultaneously on the real body and the avatar induced a Full Body Illusion. The volunteers were confused as to where their body was and they partly identified with the avatar. More than 70% of participants felt that the touch they had felt on their body was derived from the stroking seen on the avatar.

Data revealed a continuous widespread decrease in skin temperature that was not specific to the site of measurement and showed similar effects in all locations. The changes in body temperature "were highly significant, but very small," write the authors in the study, adding that the decrease was in the range of 0.006-0.014 degrees Celsius.

The recorded temperature change was smaller than an earlier study found (0.24 degrees Celsius) that looked at fluctuations during rubber hand illusion, probably because the latter used a hand-held thermometer over longer periods and different regions of the body, the authors explain.

"When the brain is confronted with a multisensory conflict, such as that produced by the Full Body Illusion, the way we perceive our real body changes. This causes a decrease in our body temperature, " says Dr. Roy Salomon, a postdoctoral fellow at the EPFL and the lead author of the study.

The scientists also say that the field of cognitive neuroprosthetics carries great promise for new prosthetics that are based on a neuroscientific understanding of the link between body and mind.

"This study helps us to understand the brain mechanisms that underlie the bodily aspects of consciousness and idea of 'self'. It may contribute to the design of novel prosthetic devices and treatment of pain, for example, after stroke, amputation, or tetraplegia," says Prof. Olaf Blanke, director of the newly founded Center for Neuroprosthetics.

"This type of research may also help to understand and treat psychiatric disorders, such as schizophrenia and depression. We hope that by identifying the mechanisms involved in these processes and how they are altered in psychosis we can help these patients," adds Dr. Salomon.

Dr. Salomon and colleagues are currently investigating how to help treat psychiatric disorders through understanding the cognitive and neural mechanisms involved in these disorders as part of the National Center of Competence in Research (NCCR)'s project titled The Synaptic Bases of Mental Diseases (SYNAPSY), financed by the Swiss National Science Foundation.


Story Source:

The above story is based on materials provided by Frontiers. Note: Materials may be edited for content and length.


Journal Reference:

  1. Olaf Blanke, Roger Gassert, Christian Pfeiffer, Melanie Lim, Roy Salomon. Full body illusion is associated with widespread skin temperature reduction. Frontiers in Behavioral Neuroscience, 2013; 7 DOI: 10.3389/fnbeh.2013.00065

Cite This Page:

Frontiers. "Full body illusion is associated with a drop in skin temperature." ScienceDaily. ScienceDaily, 30 July 2013. <www.sciencedaily.com/releases/2013/07/130730123247.htm>.
Frontiers. (2013, July 30). Full body illusion is associated with a drop in skin temperature. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2013/07/130730123247.htm
Frontiers. "Full body illusion is associated with a drop in skin temperature." ScienceDaily. www.sciencedaily.com/releases/2013/07/130730123247.htm (accessed September 2, 2014).

Share This




More Mind & Brain News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
Coffee Then Napping: The (New) Key To Alertness

Coffee Then Napping: The (New) Key To Alertness

Newsy (Aug. 30, 2014) Researchers say having a cup of coffee then taking a nap is more effective than a nap or coffee alone. Video provided by Newsy
Powered by NewsLook.com
Young Entrepreneurs Get $100,000, If They Quit School

Young Entrepreneurs Get $100,000, If They Quit School

AFP (Aug. 29, 2014) Twenty college-age students are getting 100,000 dollars from a Silicon Valley leader and a chance to live in San Francisco in order to work on the start-up project of their dreams, but they have to quit school first. Duration: 02:20 Video provided by AFP
Powered by NewsLook.com
Baby Babbling Might Lead To Faster Language Development

Baby Babbling Might Lead To Faster Language Development

Newsy (Aug. 29, 2014) A new study suggests babies develop language skills more quickly if their parents imitate the babies' sounds and expressions and talk to them often. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins