Specific areas of the brain can be controlled by using light to target genetically modified neurons, a technique called optogenetics It can treat everything from paralysis to blindness.
Now, using the same technique, a group of scientists from Northwestern University have managed to schedule social interactions among mice for the first time, something that may help to better understand how hierarchies and relationships are formed in complex groups of individuals.
Optogenetics is based on the idea that some cells contain proteins that make them more sensitive to light than others, and by inserting genes that confer these characteristics into new cells, their behavior can be altered when exposed to light. Scientists from Northwestern University They were able to do this in genetically modified mice by equipping them with neurons altered with a gene from light-sensitive algae, with the help of a newly developed brain implant.
The implant is half a millimeter thick and is placed under the skin, on the outer surface of the skull. A thin, flexible probe equipped with LEDs is then placed down into the brain, so that researchers can operate the light in real time via near-field wireless communication from a nearby computer.
Being a wireless technology, it allows mice to move freely while being analyzed.
Thus was born the first optogenetic study of social interactions between groups of animals. They succeeded in activating neurons in the brain region associated with higher-order executive function. This led to an increase in the frequency and duration of social interactions between the mice, which could be reversed by turning off the stimulation. Scientists could also arbitrarily select a pair of mice for further interaction.
The technique is not currently approved for use in humans, but it will aid in research and in the study of complex group interactions and how the brain functions when we communicate with other people.
We now have the technology to investigate how ties are formed and broken between individuals in these groups and to examine how social hierarchies emerge from these interactions.
The research was published in the journal Nature Neuroscience.