Interesting thing I learned in Class

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I learned in neurobiology today about something called "Blind Sight"...

This is where ppl have a lesion somewhere in their brain (i forget specifically, lol)... but it basically jacks their visual cortex so that they are completely blind. But the interesting thing is, they are still able to process visual information.

If you shine a light at the person's face and ask them, "Can you see "this," they'll say no. But if instead, they shine the light and say, "point towards the light," the person is able to do so.

Same thing happens if you hold objects in front of their face.... They say they can't see anything but if you ask them to grasp the object, the person extends their hand out in the correct direction... And if you hold a basket ball versus a golf ball and ask them to reach for it, the person is able to do so and also adjust their hand accordingly to appropriately grasp a Bball or golfball.

Also, they are able to recognize facial expressions from pictures ~ 70% of the time as well.... without "seeing" anything

They can do a control to show that people with this condition still have functional eyes: We have what's called a blind spot, where our optic nerve comes into the eyeball... Our striatum automatically fills in that part of the visual field for us and is why you don't see a black spot (or two) when you look at stuff... Anyway, when they shine a light in these people's eyes, they can perceive the light UNLESS it is shined directly onto the blindspot... then the people can't perceive anything.

I found this interesting, given that ASDs have issues with face recognition and motor skills.... Blind sight doesnt make a direct connection to ASDs, but i find it fascinating that there are independant visual pathways outside of our visual cortex. Maybe damage to whatever those pathways are helps to contribute to autism. They don't know what these pathways are.

Daniel Dennett wrote a pretty good explanation of 'Blind Sight' in one of his books. It's a pretty sweet phenomenom.

Yes, I learned about that and a lot of other interesting things in the 2 neurobiology classes I took. There's a book about various interesting results of brain lesions called, "The Man Who Mistook His Wife For a Hat". I've never read it, but I think it's pretty easy to find at public libraries. I don't remember the author's name. The title refers to a famous brain lesion case resulting in the inability to recognize objects. So the patient could see, but he couldn't connect what he was seeing to the name for it. There's another brain lesion that makes it impossible to recognize faces, but other visual information can be processed normally.

Almost like it makes all visual stimuli subliminal!

I am the complete opposite. I can see things and take in that information. But I can't use that information visually. I have no imagination. They often say ASD lack imagination. But I literally can't imagine. Rather than being unimaginative in the general sense I can't see images in my head at all other than what is in front of my eyes or in deep sleep. If you asked me to imagine a tree I couldn't do that. If you pointed at an object and asked me to look away and visualise it I couldn't do that. I don't have a name for this condition but it is fair to say it is debilitating. I sort of think in definitions, but it is somewhat lacking in detail. No I do not think in words because I don't ‘see’ them. I can ‘hear’ my thoughts on an outer level, but that is no good for recall, apart from to express my frustration at it.

I believe that my cognitive problems would be less if I had a visual sketch pad in my mind. I have been pushing hard for a neurophilological evaluation of this and other things, but my consultants have drawn a blank (no pun ) on who to refer to thus far.