The brain can represent reality without the help of the senses

The brain has the innate ability to represent reality even when it does not receive sensory stimuli, such as images and sounds.The discovery, entirely Italian, sheds new light on a capacity of the most complex of organs and indicates that there are no scientific bases to discriminate against those who do not see or hear. "The result confirms that the ability to represent reality is programmed and that, even in the absence of specific sensory information, there can be the same functional architecture," say Pietro Pietrini,. director of the Molecular Mind Lab of the IMT School of Lucca and one of the authors of the research published in the journal Nature Human Behavior. The study, coordinated by Emiliano Ricciardi and whose leading author is Francesca Setti, was also assisted by the University of Turin.

Point of arrival of more than 20 years of studies conducted by this research group, the study was conducted on people who are deaf and blind from birth, and on a control group of people able to see and hear and is the result of more than 20 years of studies conducted by this research group. Every volunteer listened or watched the children's film ‘One Hundred and One Dalmatians’: the blind listened to the audio description of the film, while the deaf watched the version with subtitles without sound. The same experimental conditions were used for hearing and sighted participants, and each group's reactions were recorded by means of Functional Magnetic Resonance Imaging, Setti said.

Comparing the data of each group, "a high degree of similarity in sensory activity between those who see only and those who only hear emerged". This, she added, means that a part of the cerebral cortex, called the superior temporal cortex, reacts very similarly in all individuals to arrive at an integrated perception. That is to say that this part of the brain is activated exactly in the same way in all cases, even when it does not receive visual or auditory stimuli and the reason is that it has been genetically programmed in this way. "Any brain response in common between these individuals - observed Ricciardi - is indicative of an innate function, present regardless of sensory experiences that occurred after birth".

This unties a knot of the debate, open for years, on how much the human brain depends on sensory experience and how much it is instead predetermined, that is, on how innate it is and how much it is instead learned. "It is an important result because - observed Pietrini - it constitutes a further step to promote policies of inclusion of disability. We can argue that the more we know about the brain, the more we realize that there are no scientific grounds to discriminate against people with disabilities." It is a matter of "intervening on the ways in which the content is used", he added. "Our brains are programmed from birth to overcome the obstacles that stand between us and the world around us."