Reading is a relatively modern and human talent. Therefore, how the words were recognized visually became an enigma for neuroscientists. Because the nervous system responsible for reading could not have evolved for this purpose.
Assist. From the Department of Neurosurgery, University of Pittsburgh. Assoc. Dr. According to Avniel Ghuman, parts of the brain dedicated to reading have been the subject of a violent debate for almost 200 years. Leading neuroscientists of the 19th century, Wernicke, Dejerine and Charcot, discussed whether there was a visual center for words in the brain.
In recent years, discussions have focused on the left middle fusiform gyrus, some of which are referred to as the “visual word field”. A recent study by neuroscientists from Pittsburgh points to these debates and sheds light on our understanding of the neurobiology of reading.
Ghuman, Elizabeth Hirshorn of the Pittsburgh Learning Research and Development Center and colleagues from the Center for Informatics Neural Basics in the study published on July 19 in the journal Proceedings of the National Academy of Sciences 19 visual vocabulary ” In order to study the role of the brain, they examined neural recordings and brain stimulation of four epileptic patients. Patients preferred surgical treatment for drug-resistant epilepsy and volunteered to participate in the study. Neurosurgeons placed electrodes in the visual word field of patients as part of the surgery. This provided a unique opportunity to understand how the brain recognizes written words.
First, patients’ ability to read words was counteracted and painless electrical brain stimulation was used by electrodes to prevent the usual function of the visual word field. One patient perceived the letters significantly wrong. Another had the feeling that some words and parts of words were there, even though they were not actually in the text. The excitation of this area did not have a disturbing effect on the naming of objects and faces (a short video about excitation can be seen here: https://youtu.be/N4FYG7UW-vM).
In addition to stimulation by electrodes, the activity of the relevant field was also recorded while patients read the words. If analysis of brain activity spread over several hundred milliseconds using machine learning techniques, it could be said by the researchers which words the patients were reading at a given moment. This shows that the neural activity of the area involved encodes information about visual words and can be used to distinguish even words with only one letter of difference.
“This study shows that the visual vocabulary field is elegantly tuned to the finer details of written words, and this field has an important role to play in the brain representation of what we read. Stimulation of the perception of words and letters as a result of stimulation provides direct evidence that the visual vocabulary field plays a special role in reading, Hir says Hirshorn. Sonuç These results also provide important implications for the understanding and treatment of reading disorders. The activity of the visual vocabulary field, together with its interaction with other brain regions involved in language processing, may be a sign of further reading. A better understanding of this neural system can be important for diagnosing reading disorders and developing targeted therapies. ”
According to Ghuman, with modern techniques of brain recording and advanced analysis methods, we are ultimately able to answer centuries of questions about the brain and mind and contribute to the understanding of reading disorders.