Researchers from the Sleep Laboratory of the Faculty of Medicine of the University of Lisbon have dealt with the question concerning the ways in which blind people dream; scholars have come to a curious and unexpected conclusion establishing that the dreams that animate the sleep of blind people from birth … are the same as ours!
The study by the Portuguese university integrated previous studies on the subject, which dealt with the topic from a psychological point of view, with other methods of analysis. The researchers, in fact, used both qualitative and quantitative tools for measuring dream activity, coming to discover that blind people, in their dreams, view images just like us, although they have never had experience of them.
Helder Bértolo, biophysicist in charge of the study, says that as with the sighted, even in the REM sleep phase of the blind, both the occipital visual cortex, that is the part of the brain where the images arrive, is activated. This would mean that dream activity is visual even in the blind.
Another “proof” of the visual character of the dreams of blind people since birth was the result, always in the same study, of the so-called graphic analysis of the drawings on the dreams made by the volunteers (both blind and non-blind) made upon awakening. The researchers explain that, taking the drawing of the human figure as an example, between the blind and the blind, the graphic analysis shows that on as many as 51 lines of graphic identification, the only discordant element is found in the part of the ears, which the blind they draw significantly larger (probably because they are touched in a person’s recognition process).
Having ascertained that blind people dream exactly like blind people, it is normal to ask another question: how do blind people see (albeit in a dream) things they have never actually seen? The scientific community, for now, is only speculating. It is believed, in fact, that images can be generated by the “cooperation” between the activity of the visual cortex with the activity of the other sensory organs, such as touch, hearing, smell and taste. It is not excluded, however, that the human being possesses a sort of database of “innate” images, used to preserve the species.
Published in “Cognitive Brain Research”, the research of the sleep laboratory of the University of Lisbon was awarded at the congress of the European Sleep Research Society.