Our 'free will' spot lies at back!

23 May, 2009

There are specific brain regions that are involved in the consciousness of one's movement. In six out of the seven cases, the cancers were located far from the parietal cortex and other areas.

FRENCH RESEARCHERS have found the place where the free will resides in the brain. Scientist, Angela Sirigu, who is a neuroscientist at the CNRS Cognitive Neuroscience Centre in Bron, said that the place lies towards the back of the human brain called the parietal cortex.

The findings have been based on the analysis of an experiment by Sirigu’s team which included Carmine Mottolese, on about seven patients who underwent brain surgery to remove the tumours.

The researchers discovered this spot when a neurosurgeon electrically jolted this area in patients undergoing surgery. They felt the desire to wriggle their finger, roll their tongue or move a limb. Stronger electrical pulses convinced the patients that they had actually performed these movements, in spite of their bodies remaining motionless.

Sirigu said that it tells us that there are specific brain regions that are involved in the consciousness of one’s movement. Out of the seven, in six cases the cancers were located far from the parietal cortex and other areas that Mottolese stimulated.

All the patients were awake during the surgery. The teamwork points to two brain areas involved in making the decision to move a limb and then execute the action.

Sirigu believes that the parietal cortex predicts the future movements and sends instructions to another brain area, the premotor cortex, which returns the outcome of the movement to the parietal cortex. The scientist said that in day-to-day life, we rely on both the regions of the brain to move about. We need both systems, the parietal and premotor cortex to generate intention and check whether this is followed through.

These findings were published in the ’Science’ journal.