Scientists at Harvard Medical School have stimulated new neurons to grow in the neocortex of the brains of laboratory mice, which was not thought to be possible.
The neurons were induced by triggering stem cells, or precursor cells, that already exist in the brain. Previous research had found that transplanted brain cells can form new neurons, but the results of this research indicate that this may not be necessary.
The new cells integrated themselves into the existing brain circuitry by moving to areas of the brain which had dead neurons, and grew axons (connections) into the proper tissue.
During the research, which was performed by neuroscience professor Dr Jefrey Macklis, Sanjay Magavi and Blair Leavitt, growth in specific neurons was triggered by killing others. However, this is not thought to be required for any potential future treatments.
The research is to continue by examining what triggers the creation of neurons, and the development of drugs that does not involve the killing of cells.
The researchers added that any new treatments for neurological conditions were many years away.
Bruce Dobkin, director of the neurological rehabilitation and research programme at the University of California at Los Angeles was cautious of the research saying, "We just have to keep in mind that you can do things in the brain of a mouse that you can't necessarily do in people." He continued saying, "and the fact that a connection sprouted does not mean it functions like the neuron it replaced."