Research, Why Our Eyes Don't Jump

When our eyes are looking at the world, they move 4-5 times a second or, in other words, 150 thousand times a day. So why is it that the world doesn't move with them, but is perceived as being fixed? An all-Italian research has understood why. The study, published in August's number of Nature Neuroscience, is signed by two scientists from the Faculty of Psychology at the università Vita-Salute San Raffaele: Concetta Morrone, a lecturer at the university on via Olgettina and researcher at the Institute of Neuroscience of the National Research Council in Pisa, and David Melcher, the American 'brain' who has chosen to work in Italy.

The first question is this, said Morrone: 'When we walk, run, jump and move, why is it that the objects we see remain fixed in the same position?'. It's all thanks to neurons. By means of a mechanism that's still being researched, 'they act like lots of small, super-intelligent film cameras'. Each one keeps its lens fixed on a precise area and, thanks to clever direction by the brain, it comes into operation when it's needed and prevents the world from moving along with us.

What are the practical benefits of the discovery? 'Medical and technological', Morrone replied, 'it could help patients who have unstable vision as a consequence of an ictus, for example, or for research into new film cameras that are able to reproduce the signal from the brain'. But our work is above all cognitive. 'What we have discovered about sight might also be true for the other senses, starting with hearing'.