Good morning all,
In our last lecture, we discussed the characteristics of neurons, and how they use electricity (specifically, changes in membrane potential) to send information to their targets. Many of our BIOL 240 lab sections this week explored this concept via EEGs (electroencephalograms), which are recordings of skin potentials that occur due to changes in brain electrical activity.
I also mentioned in lecture that many of our pharmaceuticals are designed to chemically influence neural function. You may also know that electrical manipulation of the bran is not far behind. Scientists have known about the electrical properties of nervous tissue for many decades, and in recent years, we have been able to apply this knowledge to stimulate the brain.
Rather than using electrodes to measure the electricity coming from the brain, what if we use them to apply electricity to it? As you would expect, we can cause neurons to become activated by passing electrical current over them.
There are many different forms of neural stimulation possible, from very local applications to nearly whole-brain methods. Increasingly, we are getting better at using small-scale, focal stimulation to apply electricity at select locations, in order to change the function of circuits in that area. Below is a link to a recent report of one such use of this method.
Think about all of the different aspects of our behavior, emotions, and performance that are controlled neurally. What if we could adjust them, with a battery?
Have a great weekend -
As a sign of how much of the complexity of the nervous system remains to be elucidated, I'm forwarding a link to a news story that came out a few days ago, describing a new type of neuron in human brains that was previously unknown, and which does not appear to have a counterpart in mouse brain. Given how commonly mouse models are used to investigate human neural (and other) function, it's a good reminder of how much we have yet to learn!
And, the fact that this follows on the heels of another report of a new type of neuron in the eye (from a few years ago), this also is a good reminder of how cellularly complex neural tissue is compared to many other tissues - we don't routinely hear reports of new cells types in other organs.
Have a good (long) weekend. See you on Wed - don't forget to take care of those first two quizzes by then.