stimulation over the visual cortex or another control site not involved in Braille reading. Results showed that when TMS was applied over the visual cortex, congenitally blind individuals made significantly more mistakes, and they reported distortions in tactile perception. In the second study, undertaken in 2006, the effect of repetitive TMS (rTMS) was tested on Braille reading performance. A difference from the first study mentioned above, is that in this study, the effect on Braille reading was measured after and not during the TMS application. In brief, a group of congenitally blind participants were asked to read as quickly as possible, a list of Braille words that were written in an unfamiliar (Finnish) language. Both reaction times and number of errors were measured. The same list was repeated three times in a row, a procedure which induces repetition priming, meaning that time needed for reading the word list will be shorter with each successive repetition. Next, rTMS was applied for 15 minutes over the visual cortex or SI (control). Immediately thereafter, participants received a new word list which they had to read again three times. Results showed that following rTMS over visual cortex, compared to SI, blind participants made significantly more errors and were significantly slower. In addition, the repetition priming effect was significantly smaller following rTMS over the visual cortex. Together, the results of both studies show that the visual cortex is indeed functionally involved in Braille reading in congenital blindness. It is mentioning a unique case report of a congenitally blind proficient Braille reader, who after bilateral damage to the visual cortex following a stroke was no longer able to read Braille, despite the fact that tactile perception remained unchanged. Indeed, the patient did not notice any impairment in touch discrimination when trying to identify the roughness of a surface or locate items on a board. A question that may emerge is whether similar functional reorganization can also happen in individuals with normal vision who have learned to read Braille. This was examined in a quite recent study in 2016, where healthy sighted people were trained to read Braille. The authors monitored changes in brain activity that occurred following 9 months of daily training with Braille reading. Subjects showed enhanced activity for tactile reading in the visual cortex, including the visual word form area (VWFA) that was modulated by their Braille reading speed and strengthened resting-state connectivity between visual and somatosensory cortices. Moreover, TMS disruption of VWFA activity
stimulation over the visual cortex or another control site not involved in Braille reading. Results showed that when TMS was applied over the visual cortex, congenitally blind individuals made significantly more mistakes, and they reported distortions in tactile perception. In the second study, undertaken in 2006, the effect of repetitive TMS (rTMS) was tested on Braille reading performance. A difference from the first study mentioned above, is that in this study, the effect on Braille reading was measured after and not during the TMS application. In brief, a group of congenitally blind participants were asked to read as quickly as possible, a list of Braille words that were written in an unfamiliar (Finnish) language. Both reaction times and number of errors were measured. The same list was repeated three times in a row, a procedure which induces repetition priming, meaning that time needed for reading the word list will be shorter with each successive repetition. Next, rTMS was applied for 15 minutes over the visual cortex or SI (control). Immediately thereafter, participants received a new word list which they had to read again three times. Results showed that following rTMS over visual cortex, compared to SI, blind participants made significantly more errors and were significantly slower. In addition, the repetition priming effect was significantly smaller following rTMS over the visual cortex. Together, the results of both studies show that the visual cortex is indeed functionally involved in Braille reading in congenital blindness. It is mentioning a unique case report of a congenitally blind proficient Braille reader, who after bilateral damage to the visual cortex following a stroke was no longer able to read Braille, despite the fact that tactile perception remained unchanged. Indeed, the patient did not notice any impairment in touch discrimination when trying to identify the roughness of a surface or locate items on a board. A question that may emerge is whether similar functional reorganization can also happen in individuals with normal vision who have learned to read Braille. This was examined in a quite recent study in 2016, where healthy sighted people were trained to read Braille. The authors monitored changes in brain activity that occurred following 9 months of daily training with Braille reading. Subjects showed enhanced activity for tactile reading in the visual cortex, including the visual word form area (VWFA) that was modulated by their Braille reading speed and strengthened resting-state connectivity between visual and somatosensory cortices. Moreover, TMS disruption of VWFA activity
braille_report_final_version.docx