Posted by alexandra_k on February 17, 2020, at 3:07:43
In reply to Re: No person born blind has ever been Schizophrenic:, posted by undopaminergic on February 13, 2020, at 13:07:33
A person who has never been able to see doesn't know what it is like to be able to see. As such, they wouldn't be able to say whether they were having seeing-like experiences or not.
Similarly for a person who has never been able to hear and auditory-like experiences.
There is some evidence of neural plasticity so that the brain regions devoted to processing information from one source may be co-opted to processing information from a different source when that usual source is absent.
For example, if a person is born blind then the parts of their occipital cortex that would, in a sighted individual, be activated in response to visual stimuli, can, instead, come to be activated in response to auditory stimuli or tactile stimuli or vibrational stimuli.
People who are born blind develop hyper or super or special sensistivity in processing auditory / tactile / vibrational stimuli. They can sense when a person is in the room etc because they are more sensitive to / attentive to vibration.
There is some evidence that when a person experiences hallucination what is going on is that there is cortical activity without sensory input. So, for example, when a person is having an auditory hallunication they are experiencing activation of the auditory cortex but the activation is abnormal in the sense that it isn't occuring in response to external information but is being top-down driven (as it may be in dreams).
When a person thinks to themselves in words hearing or sub-vocal speech / motor areas of the cortex may be activated.
When a deaf person thinks to themselves in sign language...
Does the auditory cortex activate?
If a person is blind and they have activation to their visual processing cortex without external stimuli being present (e.g., in a dream) then what sort of experience do they have? A visual one? What sort of stimuli would trigger that activation in them if that activation was triggered by external stimuli?
I don't know.
I guess I was wondering, somehow, if all the extra brain power devoted to one modality may make it more resilient to breaking.
Like how if you are genuinely bilingual (two languages before 7ish years old) then language is more distributed in your brain so you are more resilent to losing language if you have localised trauma e.g., stroke.
poster:alexandra_k
thread:1108443
URL: http://www.dr-bob.org/babble/20200104/msgs/1108485.html