Fifteen years ago, optogenetics made its way in the world of science. Optogenetics is a method of studying nerve cells, or neurons, by activation through the use of laser lights.
Just recently, a group of scientists in New York experimented with lasers, aiming them into the brains of some mice, making them perceive lines that are not really present. This is the first time, according to the researchers that visual perception has been created in the laboratory.
Neuroscientist and psychiatrist Conor Liston from Weill Cornel Medicine describes their work as "technically amazing" and says that neuroscientists will be very interested in their experiment as monitoring and controlling neurons could be a big step in answering major questions about how the brain works.
Lead researcher Karl Deisseroth, along with his team, first monitored the neurons in the brains of the mice that were able to view lines, either horizontally or vertically oriented. Then the mice have been trained to lick water coming from a small spout placed in front of them whenever they saw the orientation of lines, depending on which orientation they were trained on. The researchers initially showed the mice some very faint real lines that were gradually becoming fainter. When the lines got so faint that the mice started to struggle with the experiment, scientists proceeded with optogenetic stimulation to improve their performance.
After that, the researchers subjected the mice to total darkness without any kind of visual input. Here, they found that stimulation of around 20 of the many neurons that respond to sight helped the mice see the correct lines and lick the spout as they were trained.
Of course, leading to the success of the experiment were precise lasers carefully controlled by liquid medium and the recent discovery of ChRmine, a protein stimulated by light. ChRmine can be activated by very dim light, which is a useful trait not only for this experiment but also for the practicality that too much light can cause damage to the brain.
This experiment has led Deisseroth to think that a similar approach may be made in the study of other senses and perceptions and may possibly aid in more understanding and controlling more complex brain activities.
