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Usually, research on the brain goes from something presented to the brain--an image, for example--to brain activity in response to that image. However, in this line of research, the researchers are doing the opposite. They started with brain activity that was generated when participants viewed something and then tried to infer what that something was. Really cool stuff!

What you are seeing in this video is a compilation of the brain activity of three subjects. If you watch carefully, for each stimulus on the left, you will see three brief recreations of what the brain recorded on the right, one from each subject.

I was especially struck that the subjects "saw" scenes with Steve Martin but their brains didn't register the details of the set behind him. This is consistent with research on inattentional blindness; astonishingly, our sense of a unified and rich reality is an illusion. We actually attend to three or four things in our environment, and the rest is filled in by the brain. I find this very profound. Do you?

This morning my brother sent me this photo of a place in northern Minnesota that is dear to both of us; its beauty was such that I gasped out loud when I saw it. Later in the day I thought of that involuntary gasp at beauty when I came across this article from Scientific American on "the neuroscience of beauty"

"the aesthetic system of the brain evolved first for the appraisal of objects of biological importance, including food sources and suitable mates, and was later co-opted for artworks such as paintings and music.."

So my anterior insula lets me know when something is tasty/yummy or nasty/vile, not only with edibles such as apples but also with intangibles such as art and music. I find that fascinating.

In today's class, Dr. Gewirtz described the neural impulse (or action potential) and neural communication from the pre-synaptic cell to the post-synaptic receptor. You can find terrific animations of this process on YouTube. I have one that I'd like to share with you, but I can't embed it (because embedding was disabled.) So, I'll use a screenshot and import some visual interest and post THIS LINK to the video on YouTube. Click on the link and bingo!

This video shows the stages of neural communication:
1) the dendrites receiving an electrical impulse,
2) (about 10 second in) the electrical impulse racing down the axon, negative ions leaving the cell
3) (around 18 secs) positive ions entering the axon;
4) (around 31 seconds) the message reaching the terminal field and the release of neurotransmitters from the synaptic vesicles into the synapse;
5) the neurotransmitters reaching the post-synaptic receptors.

It does not illustrate the final step in neural transmission, that of the clearance of the neurotransmitter from the synapse either through recycling/reabsorption or through degradation via enzymes. Does this video help you visualize the process?

By the way, has it occurred to you that you are learning the British pronunciations for these processes (and sometimes the British term?) thanks to our British professor?

This post from Section 23 on eyewitness identification reminded me of work at the University on prosopagnosia, the inability to recognize faces. On Wednesday, we'll see a video of a woman with this condition. I was shocked to learn that it may be more common than previously thought.

"Imagine you're a school-aged child and this is your reality: You go to school and nobody looks familiar; your classmates are essentially a sea of faces, none of which is recognizable from the day before. A girl walks over to chat and she seems to know a lot about you, but you can't place the face--and she seems equally perplexed, if not a bit agitated. "

"Then, at a family gathering, you find out that the strange faces in your house are actually cousins, although you wouldn't know them from your classmates, whom you wouldn't know from anyone else on the street. "

"The condition is known as prosopagnosia, or "face blindness," and according to U professor Al Yonas, it may affect 1 to 2 percent of the population. The problem is, very few people are aware of it, which makes proper diagnosis problematic. Yonas is hoping to change that reality."

So think about it. Imagine a police line-up, where they want you, the eye witness, to identify a criminal. What if you were one of those 1-2% of people who don't realize they have prosopagnosia? Would justice be served? Would you be able to identify the culprit?

The image above is from the original article. According to the caption, there is one recurring face in each row...can you see it? Are you ready to be an eyewitness?