How the brain understands pictures..

[IGBT]

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The figure is famous: a deceptively simple line drawing that at first glance resembles a vase and, at the next, a pair of human faces in profile. When you look at this figure, your brain must rapidly decide what the various lines denote. Are they the outlines of the vase or the borders of two faces? How does your brain decide?
It does so in a fraction of a second via special nerve circuits in the brain's visual center that automatically organize information into a "whole" even as an individual's gaze and attention are focused on only one part, according to Johns Hopkins researchers writing in a recent issue of the journal Neuron.

 

[CycloWizard]

There are entire journals dedicated to the subject of how the brain 'sees' - from its control of the accommodative function (how the brain focuses the eye), to interpreting the retinal signals to form images, to assigning a group of signals to be an object. Very fascinating subject that I've recently become aware of since it loosely pertains to my own research. Visual Neuroscience is probably the best journal dedicated to the topic.

 

[Jeff7]

I get the idea that the brain functions based on patterns. You begin to learn patterns as soon as you are able to perceive anything. These can be in the form of either physical patterns, or ones through time - one event tends to lead to another.
When you see something, the brain uses massively parallel processing and data recall to match what it sees to pattern types. In the vase/face example, the dark central thing stands out, because the brain knows, or has learned, to look at what is in the middle first. The pattern resembles a heavily carved vase. Then, you move to the peripheral of the scene, and notice two undetailed faces in profile.

 

[EightySix Four]

Not completely on subject but it does relate. There was a guy in a car wreck who damaged a very small portion of his brain, after the fact he could NOT recognise human faces in any way. Not even his own. So the brain possibly has different areas used for recognising different kinds of objects?

 

[f95toli]

Originally posted by: crazySOB297
Not completely on subject but it does relate. There was a guy in a car wreck who damaged a very small portion of his brain, after the fact he could NOT recognise human faces in any way. Not even his own. So the brain possibly has different areas used for recognising different kinds of objects?

Yes and no, as far as I remember there is a special area of the brain dedicated to recognizing faces. Or to be more specific, the area is resonsible for making the "connection" between the picture of a face and the person the face belongs to. I.e, when this area malfunctions you still able to understand that you are looking at a face but you are unable to "understand" that it is e..g your wifes face.

Note that is still possible to "compensate" for this on a "higher level", you can still identify faces on an intellectual level in the same way you identity e.g. a building ("I am looking at a face with blue eyes, big nose etc, the conclusion is that it must be my wife"); it is the "automatic" detection that does not work.

Apparantly, there is some evolutionary benefit in having a automatic, rapid, centre for facial recognizion.

 

[MrDudeMan]

Originally posted by: f95toli

Originally posted by: crazySOB297
Not completely on subject but it does relate. There was a guy in a car wreck who damaged a very small portion of his brain, after the fact he could NOT recognise human faces in any way. Not even his own. So the brain possibly has different areas used for recognising different kinds of objects?

Yes and no, as far as I remember there is a special area of the brain dedicated to recognizing faces. Or to be more specific, the area is resonsible for making the "connection" between the picture of a face and the person the face belongs to. I.e, when this area malfunctions you still able to understand that you are looking at a face but you are unable to "understand" that it is e..g your wifes face.

Note that is still possible to "compensate" for this on a "higher level", you can still identify faces on an intellectual level in the same way you identity e.g. a building ("I am looking at a face with blue eyes, big nose etc, the conclusion is that it must be my wife"); it is the "automatic" detection that does not work.

Apparantly, there is some evolutionary benefit in having a automatic, rapid, centre for facial recognizion.

well put and interesting points. i think the evolutionary benefit statement is correct but im not sure how to quantify that. it makes sense, but then it doesnt. the brain is such a crazy and complex system...it makes my head hurt.

 

[Sushifiend3000]

Apparantly, there is some evolutionary benefit in having a automatic, rapid, centre for facial recognizion.

I would hazard a guess that it is to avoid being EATEN.

 

[glorygunk]

How the brain achieves immediate facial recognition is not well understood at all. Of course it makes your head hurt to think about how it is your head can hurt, how you know that your head hurts...etc

However, it's clear that humans are not born with this visual processing intact. If you've ever noticed, babies are very uncoordinated. For example, they often try reaching for things that are clearly out of their grasp, such as mobiles hanging over their crib (depth perception apparently requires a lot of experience). Perhaps why we all have such good facial recognition is because the first things we see as babies are our mother's faces.

Another story worth mentioning:
A man who could not see for 20 years one day received corneal transplants to restore his vision. This was a special case because throughout those 20 years he had functional retinas but his corneas were clouded, thus making him blind except to varying light intensities. Although he was once able to see in his early teens, over the latter 20 years his brain "forgot" all about visual processing. After the operation, the world literally made no visual sense at all. He would stare right at his wife with literally no recognition unless he felt her face. With great effort, he could interpret some of the letters on a printed page. Strangely, the things that interested him the most were all the different colors, and moving objects such as cars. Such things probably require only a very basic level of processing (motion and color.) Nevertheless, living in a "seeing world" presented a great amount of stress on him and caused many headaches. Often he would prefer to close his eyes for days at a time so as not to tax his brain.

OK I'll let you guys talk about it...I'm done typing

 

[Powermoloch]

Originally posted by: crazySOB297
Not completely on subject but it does relate. There was a guy in a car wreck who damaged a very small portion of his brain, after the fact he could NOT recognise human faces in any way. Not even his own. So the brain possibly has different areas used for recognising different kinds of objects?

I heard that story before, well something similar. The guy end up as normal, but his emotional attachment to certain images, or even faces of his parents are not there anymore. There was a neural pathway from the visionary cortex (fromt he back of his occipital lobe) and somewhere in between his limbic area of his brain (the emotional) had torned up apart. Because of this consequence, he could see the objects, but does not feel about it. Even his house, he'll panic like : "where am I, I need to go home". If he speaks with his parents on a phone, he could recognize them perfectly by their voice...pretty amazing.

 

[Torched]

It's funny this thread came up. I saw this article the other day:
http://www.livescience.com/humanbiology/050811_attention_problem.html
Makes me want to try it to see if I am the same.