Do we control our neurons or do our neurons control us?

When someone tells you "don't look down," how hard is it to resist? If I tell you not to think of the pink elephant in the corner of the room, do you immediately picture one staring right at you? Or how about this one (my favorite scenario) - what ever you do, don't imagine this: you're in a giant auditorium, center stage, with a spotlight on you, and you're on your knees, fists clenched, screaming at the top of your lungs, "Morrisonnn!"

If you think about it, there are so many things - external stimuli - buzzing around in the world, all competing for your attention. The text you read above is just a tiny, tiny fraction of that. Subconsciously, a colorful bird flying by may break your train of thought and catch your attention; or, a boring professor in class may not grab it at all. Consciously, you might have a hard time concentrating on studying or, on the flip-side, you might have a hard time suppressing the thing that is distracting you. What's going on in the brain during this cognitive power struggle? Or, more boldly, what is going on during active, explicit consciousness? That may never be answered but researchers in the Department of Neurosurgery at the University of California, Los Angeles (along with others at the California Institute of Technology) attempt to investigate this fascinating question.

Dr. Itzhak Fried at UCLA is a neurosurgeon who specializes in treating patients with epilepsy while implementing single-unit recording to study fascinating aspects of the human brain. Before going into surgery, patients consent to being a part of a research study that will occur in the operating room (a procedure that can soar well over $200,000...talk about fMRI being expensive!)

In class we talked a lot about single-unit recording (reading the activity of a single neuron) as being the gold standard of functional neuroimaging, in terms of both spatial and temporal resolution. We also discussed how this method is primarily restricted for use in animals, given how highly invasive the procedure is. Electrodes that are implanted into the brain cut through, damage, and kill cells, including the neuron of interest that is pierced by the electrode during recording. However, under special circumstances, (e.g., a patient going in for brain surgery anyway to have a tumor removed, or in this case, treating epilepsy by lesioning troublesome areas in the brain), single-unit recording has been performed in humans to collect pristine functional data.

The video below describes a fascinating study that evokes very intriguing and controversial questions, may lead to long-sought-after answers, and opens the door to limitless, innovative applications of science and technology. In short, electrodes were placed in neurons in the temporal lobe (think the "what" pathway, specifically the fusiform face area - critical in object recognition) that respond most when images of people's faces are presented to the subject. Researchers found single cells that respond more to one celebrity's face than to that of another celebrity (and, vice versa, a cell that responds more to the second celebrity's face than to that of the first's). Next, when the subject is asked to think of celebrity 1 without being presented with a picture, lo and behold, neuron 1 fires like crazy. Same for celebrity 2. Where this gets even cooler is when these implanted electrodes are hooked up to a computer. The computer is programmed to project celebrity 1's face and celebrity 2's face superimposed over each other, with each picture's opacity controlled by the corresponding neuron's firing rate. This "collage" is projected on a screen in front of the subject and when prompted to think of one celebrity and not the other (i.e., don't think of the pink elephant), we get a visualization of the effortful struggle with attention the subject is attempting to settle - a window into human consciousness.

A few questions I had that I want to open up for discussion are:

1) Do we control our neurons, or do our neurons, in fact, control us? When you think about it, do we think of the pink elephant because the pink elephant neuron is firing, or does the pink elephant neuron fire because we think of the pink elephant ? And who the hell is doing all the decision making?

2) What happens if you find every cell that responds best to Marylin Monroe, and you kill that cell? Would you not be able to respond as well to Marylin Monroe's face anymore? Can surgeons selectively delete a memory? I thought this is the sort of thing my teachers in every neuroscience-related class preached against - the idea that single memories are housed physically somewhere?

3) Think of all of the applications this can have! Imagine if we could hook up cells that respond to shapes and colors to computer software like Adobe Photoshop...an artist could just think of a painting and...boom...a beautiful work of art. If every "object recognition" cell was hooked up to a monitor, could we get a video dramatization of your dreams while you sleep? What other cool or therapeutic applications can you think of? To me, the future always seemed like a place where we could plug our brains in like in the Matrix. Many researchers are pushing boundaries in this field - the brain-machine interface is a booming area in neuroscience.

Here's a YouTube link so you can post it on all of your friends' Facebook walls and have something deep to discuss over dinner in Loyola's delicious dining halls.