Scientists at the California Institute of Technology have developed a way of implanting an optical lens directly into the amygdala of a living mouse’s brain to watch the neural activity taking place. The lens is a thin glass rod that is pushed deep into the brain, while an imaging microscope connected to it lets the scientists have a look inside.
Of course, the brain is naturally dark and there aren’t any sparks whenever you come up with a brilliant idea. But, using a bit of genetic engineering, the scientists introduced a fluorescent protein into the neurons of the mice being studied so that the cells release it whenever they’re active.
The researchers then introduced the mice to other mice, both males and females, and watched which neurons were being activated. They found that some neurons only lit up when males were present, while others reacted only to females, and yet others lit up to both sexes. Correlating the social activity of the mice to the neural activity taking place inside their brains allowed the scientists to make new findings, such as actually how the brain changes over extended periods while the mouse adapts to new social situations. They were able to conduct studies for time periods as long as three months, an impressive feat that opens up a world of other studies that will help us to understand how our brains work and how to fix the diseases that they’re susceptible to.
Related papers: Study in Nature: Social behaviour shapes hypothalamic neural ensemble representations of conspecific sex…; Study in Cell: Neuronal Representation of Social Information in the Medial Amygdala of Awake Behaving Mice…