Neuroscience Seeking the Self

Experimenting with a rotating chair

Experimenting with a rotating chair

To be presented next year at the largest scientific conference in the US, EPFL researchers search for the seats of self-consciousness by studying brain activity in a rotating chair.

Questions concerning the notion of the self, such as “Who am I?” and “What is the self and where are its boundaries?” have long lived in the domains of philosophy and psychology. But behavioral neurobiologist Olaf Blanke and his team from the Brain Mind Institute at EPFL are studying the self through a series of unconventional empirical studies. He will present his research next February at the AAAS 2011 conference in Washington D.C. One research project employs a rotating chair—much like those used to train fighter pilots and astronauts—to discover how the brain processes bodily perception.

Human centrifuge

The rotating chair (or human centrifuge) is used by Blanke and his team to investigate the vestibular system, a “sixth sense” of sorts originating in the inner ear and essential for maintaining balance and spatial coordination. The scientists hope to find out how and where in the brain this balance system is represented, the so-called vestibular cortex, by systematically and mechanically provoking vestibular sensations while recording brain activity.

“In contrast to conceptual notions of self-consciousness, a new, data-driven theory based on the neurobiology of body representation during a variety of experiments is emerging,” asserts Blanke.

A neurobiological model of the self

Previous work in Blanke’s lab suggests that many different senses, but especially the vestibular system gives the brain a crucial reference to represent the self and its location in space. How is the self related to the balance system? And what happens when the visual input and spatial input don’t match up, as in the familiar case of two parallel, stationary trains and the feeling of forward movement of the self when the adjacent train begins to roll in the opposite direction. In the complete darkness of the rotating chair chamber, the subject experiences the movement of her body thanks to her vestibular system, although no visual input is there to back it up. Blanke is using this chair to manipulate and probe the relationship between visual and spatial information in the hopes of unlocking some of the secrets of self-consciousness.

Blanke is convinced that a deeper neurological understanding of these phenomena will lead to concrete answers that may have therapeutic results. “Decoding how the brain processes bodily perception may lead to a comprehensive neurobiological model of self-consciousness and a better understanding of altered states in neurological and psychiatric diseases,” he explains.

After three years of painstaking research, Blanke’s team at the Laboratory of Cognitive Neuroscience (LNCO) plan to publish their results from the human centrifuge experiment early next year.

For images of the experiment, please click here.

Author: Michael Mitchell + 41 79 810 31 07

Source: EPFL