For their investigations, researchers led by Alysson Muotri from the University of California in San Diego, bred numerous three-dimensional organoids from special stem cells and let them grow in the laboratory for ten months. They created the environmental conditions necessary for the development of the cerebral cortex of a human brain. The structures grew on a plate with numerous electrodes. This enabled the scientists to determine the electrical activity of the developing neuronal network. They were also able to cultivate nerve cells with GABA receptors.
 
These measurements were compared with those of brain activity of premature infants had been taken by other researchers.

Cleber A.Trujillo, Richard Gao, Priscilla D. Negraes, Jing Gu, Justin Buchanan, Sebastian Preissl, Allen Wang, Wei Wu, Gabriel G. Haddad, Isaac A. Chaim, Alain Domissy, Matthieu
Vandenberghe, Anna Devor, Gene W. Yeo, Bradley Voytek & Alysson R.Muotri (2019). Complex Oscillatory Waves Emerging from Cortical Organoids Model Early Human Brain Network
Development. Cell Stem Cell 25: 1-12. https://doi.org/10.1016/j.stem.2019.08.002

Further information:
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