Scientists make ‘ghost’ in laboratory

London: In a first, Swiss researchers have succeeded in recreating a ghost illusion in the laboratory. Patients, suffering from neurological or psychiatric conditions, have often reported feeling a strange “presence” that is felt but unseen, akin to a guardian angel or a demon.

 

Researcher Olaf Blanke’s team at Ecole Polytechnique Federale de Lausanne, Switzerland, was able to recreate the illusion of a similar presence in the laboratory and provide a simple explanation.

 

They showed that the “feeling of a presence” actually results from an alteration of sensorimotor brain signals, which are involved in generating self-awareness by integrating information from our movements and our body's position in space.

 

Blanke’s team interfered with the sensorimotor input of participants in such a way that their brains no longer identified such signals as belonging to their own body, but instead interpreted them as those of someone else.

 

The experts first analysed the brains of 12 patients with neurological disorders, mostly epilepsy, who have experienced this kind of “apparition.” 

 

MRI analysis of the patients’s brains unveiled interference with three cortical regions: the insular cortex, parietal-frontal cortex, and the temporo-parietal cortex. These three areas are involved in self-awareness, movement, and the sense of position in space.