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RFS, those are his initials, it is an individual of 70 years of age with a brain anomaly unique in the world. Can not recognize the numbers 2 to 9 . When shown a digit, only sees a mix of lines that are described as “spaghetti” and not have the slightest idea of what digit you’re looking at. Moreover, his vision is normal. For example, can identify letters and other symbols. The cause is an atrophy extensive in the cortex and the basal ganglia.
For the researchers of Johns Hopkins University in Baltimore, Maryland (USA), RFS shows that humans can have a processing extensive brain without any awareness . That is to say, that our brain can identify something as a face or a word without us to realize.
This patient, who was 60 years old when the researchers began the study in 2011, has a rare neurodegenerative condition called degeneration corticobasal (CBD) . “It is somewhat like alzheimer’s. Is degenerate, so that their symptoms get progressively worse. The symptoms begin late in life and still it is not known why some people develop it and others do not. However, unlike alzheimer’s disease, the presenting symptoms are usually not memory-related, but are the motor and somatosensory”, explains in an email to ABC David Rothlein, a graduate of Johns Hopkins and now at the VA Boston Healthcare System. In addition to the problem with digits, RFS has severe tremors and difficulty speaking due to problems of motor control with your jaw and other symptoms.
The inability to see the numbers is something unique. The team is not aware of any case like. The analogous nearest points Rothlein, it could be a phenomenon called prosopometamorfopsia by the fact that some people, due to seizures or some other disruption of the functioning of the brain (stroke, etc), they see the faces distorted (for example, half a face seems to be melting ). As in the case of RFS, this type of transformation is highly selective for one visual category, since it does not lead to the distortion of objects that are alike, “but unlike the RFS, the distortion is selective to faces and the extent of the interruption perceptive of reported cases seems to be less severe: it may still recognize that you are looking at a face!”, notes the scientist.
Interestingly, according to published authors in “Proceedings of the National Academy of Sciences”, so that the brain of RFS to function as a particular needs to be able to identify the digits. The serious problems occur only with the numbers and nothing more. “When you look at a digit, your brain has to ‘see’ that it is a digit before that you can’t see it, it is a real paradox,” explains cognitive scientist Michael McCloskey, lead author of the study. “In this document, what we did was to try to investigate what processing was done outside of his knowledge.”
A violin on a three –
The researchers found that RFS could not see anything placed near or on top of a digit. When I showed a 3 bed with a picture of a violin drawn, could not see the violin. If the image was sufficiently far away from the number, could see it normally.
To investigate the brain activity that occurs when the RFS receives stimuli are critical, the team conducted a few experiments using electroencephalography (EEG). In this way, they could record brain waves while RFS was watching a number with a face embedded. The recordings showed that his brain detected the presence of a face, despite the fact that he was not aware of this. In fact, their brain response was the same as when they showed him a face that could be seen clearly.
“These results show that the brain of RFS is performing a complex processing in the absence of awareness,” said Rothlein. “Your brain has detected the faces in the digits without his knowledge,” he adds. A second experiment of EEG with words embedded in numbers showed that the brain of RFS was recognizing the words, even though he doesn’t see it.
The key to consciousness
neuroscientists assume commonly that the visual consciousness goes hand in hand with this level of neural activity, but the team’s findings suggest that is a required neural processing additional to the consciousness, and it is this additional processing that is affected in RFS. The complex processing required to detect and identify faces, words and other visual stimuli is not sufficient for consciousness if the additional processing does not continue. “The big question is then: what makes us conscious of what we see? While we don’t have a definitive answer to this, our results are consistent with the notions that consciousness coincides with the integration of information at multiple levels of processing,” notes Rothlein.
Is it possible that something similar occurs in the brains of people with other pathologies, neural, and we have not been able to identify it? “We are busy! The symptoms that do not fall into conventional categories may be overlooked or discarded. Alternatively, a diagnosis of agnosia, dyslexia or dyscalculia would not have captured the nature of this particular problem,” argues the researcher.