The future of optogenetics

The brain is an extremely complex organ with cells called neurons that intertwine in a multitude of directions. Neurons communicate with the body an one another with chemical and electrical signals. When a neuron receives a signal it releases and electrical pulse to signal, other neurons it is connected to.
There are many varieties of neurons each with unique molecular shapes, sizes and connections to provide a task for the brain. Some have short ranges to inhibit neighboring neurons while other neurons spread over larger distances to stimulate their connecting neighbors. As it stands, human understanding of the brain is very limited and only areas of the brain can be understood for various functions.
Remarkably, the organism responsible for the discovery of this field is a pond alga called Chlamydomonas. In order to swim towards light for photosynthesis, the alga uses an organelle called an eyespot. The eyespot contains a light sensitive protein family called channelrhodopsin. By shining a wavelength of blue light at the proteins, the protein releases ions and depolarizes the cell it’s connected to.
When channel rhodopsin is inserted into a cell membrane and then illuminated, the neuron can be electrically simulated allowing scientists to turn specific neurons on. Other proteins have been discovered as well like archaerhodopsin and halorhodopsin that react to orange light and inhibit the neurons. The light-sensitive protein components of these proteins are called opsins and can be embedded into cells through safe methods commonly used in gene therapy. With both kinds of proteins at disposal, scientists are now able to turn specific neurons on or off and observe the behavior allowing a better understanding of how the brain works.
It is now possible to control the activity of specific neurons to understand how the brain functions at a lower level rather than doing a series of trial and error experiments. A study on altered genes of some fruit flies caused them to turn violent towards each other and was revealed as a chemical deficiency in some of the brains structures. By isolating which neurons are responsible for the aggressive behavior, I think that scientists will be able to confirm a relationship with the neurons and common brain diseases we are faced with today.
At this point it opens up the possibility of inhibiting specific neurons to simulate diseases, or stimulating neurons that the brain might not be able to in order to restore function to the brain.
Already there are a variety of experiments and methods being used to test this new discovery. Light is shown on treated body parts of mice in order to see how the nervous system reacts and scientists are almost able to induce seizures.
With fiber optics, light can be shown precisely in areas of interest to do these kinds of experiments and there’s definitely a potential use for this technology in medical science.
Physical augmentations could solve problems that seemed hopeless a year or two ago. The thought of people walking around with tubes coming out of their heads seems like a colorful future for cyborg enthusiasts.687px-PLoSBiol4.e126.Fig6fNeuron

Be the first to comment

Leave a Reply