Neuroscience research is surprisingly brutal - much of what we have learned about the brain, we have learned simply by opening that organ and poking anything at it. The activity is definitely not for the squeamish. The best tool for this? Most often, these are electrodes - probes in the form of needles that are inserted into the brain. Scientists use electrodes to measure the behavior of individual brain cells, give people control of their prosthetic limbs, or develop new technologies that interact directly with the brain. However, the question remains: is it safe at all?
The other day in the Journal of Neural Engineering, an article appeared on the feasibility of using electrodes in brain research. In it, neuroscientists note that studying the brain using neural electrodes can cause many problems. Some of these problems are relatively straightforward and can be solved by improving technology. For example, the surface of the electrodes that comes into contact with the brain, stimulates or records brain activity, can collapse or slip off - especially in the conscious patient.
This leads to erroneous entries; a leaky electrode will register a signal from a cell that is inactive, or produce a weaker signal than it actually is. Since we cannot always tell why (or even if) this is happening, it can be difficult for scientists to explain or support their findings.
But the biggest challenge the team faced stems from the fact that we really know very little about the brain. In particular, we know little about how brain tissue responds to electrode contact and exposure. Neuroscientists have conducted many experiments to study the brain cells that they killed or damaged when the electrode was inserted.
In fact, there are not many solutions. The article suggests focusing on areas of the visual cortex of the brain. Scientists could understand whether the cells they are studying are alive if the object of their research is to look at the image and observe the response of the cells.
Even so, scientists have concluded that our technology has pushed to the limits of what we actually know about the brain. For neuroscientists to gain confidence in their experimental results, they will need to invest in basic questions about how brains respond to electrodes and other technological interventions.
Ilya Khel