In which language do by birth deaf &blind people think?
People suffering from total deafblindness communicate via tactile signing. I assume that their thoughts would reflect this but like healthy people not all thoughts are in natural language but emotions, sensory perceptions etc.
Language is just our way of expressing an organizing our ideas/emotions. I would have to think that without Language their though processes would be much less efficient?
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2805429/ "Neuroplasticity Associated with Tactile Language Communication in a Deaf-Blind Subject"
This study looked at brain activity associated with reading braille and other tactile communication "input" modes between normal control subjects and one subject who had early loss of hearing and sight. The regions activated with aural language and reading in normal brains were also activated in the one subject as well. This study does not speak to vision exactly, IMO.
Language is built into our brain, hardwired, as is the ability to compensate for changes from normal. The above result is very much what you would expect - tactile input that has to do with language activates language centers in the brain, regardless of the mode of input. (My interpretation YMMV)
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