Psychology researchers have long understood and accepted the importance of an individual's brain activity in motor areas when interpreting the actions of others. However, much less was known about the role the body plays in helping individuals process and understand the same information.
With the help of two patients suffering from an extremely rare degenerative neurological condition, a Rutgers-Newark Psychology Professor and his team of researchers have established that the body plays a significant role in helping humans to perceive and understand the actions of others.
In the article, "Understanding Another's Expectation from Action: The Role of Peripheral Sensation," that will appear in the October 2005 issue of Nature Neuroscience, Rutgers-Newark Psychology Professor Guenther Knoblich is among a group of researchers who contend that individuals use the human body's senses to understand others actions and expectations. The researchers reached this conclusion by performing experiments with two individuals suffering from the rare neurological disorder of selective and complete haptic deafferentiation due to sensory neuronopathy. The participants are the only two known individuals in the world whose sense of touch and body movement was completely eradicated by the degenerative disease.
The individuals participated in tasks that tested their ability to gauge the weight of boxes which were lifted by other individuals and their ability to infer weight expectations of the observed individuals. Their performance was compared against a control group comprised of healthy individuals.
"In order for an individual to perform a motor activity simulation, you need to know how it feels to perform the action," Knoblich notes. "The two deafferented individuals do not feel their bodies. They must see their bodies to perform the simplest actions, such as standing upright. We asked whether their lack of body perception would also affect their ability simulate others' actions while observing them."