Using human stem cells, researchers successfully grew "cerebral organoids" in the lab, effectively creating miniature brains which may lead to new levels of understanding how the brain develops from an embryo and what causes neurological disabilities such as autism and schizophrenia.

Researchers have previously grown pieces of brain tissue from stem cells, but this is the first time a complex, three-dimensional organoid has been created, according to The Telegraph, which reports the mini-brain resembles that of a nine-week-old embryo.

Paul Matthews, a professor of clinical neuroscience at Imperial College London who was not involved in the research, told Reuters that the study "offers the promise of a major new tool for understanding the causes of major developmental disorders of the brain ... as well as testing possible treatments."

To create the brain tissue, the researchers began with human stem cells and treated them with a combination ot nutrients in order to grow tissue called neuroectoderm -- the portion of the early embryo that gives rise to the central and peripheral nervous systems.

The cells were cultivated for months before they began to resemble developing brain regions such as the retina, choroid plexus and cerebral cortex, Reuters reported after sitting in on a telephone conference with the researchers.

After two months the organoids had grown to a size of 4 millimeters (0.16 inches), which appeared to be their maximum because of a lack of blood supply. Although diminutive and nowhere near the size of a fully functional brain, there were still active neural connections and distinct types of neural tissue in the mini brains, Reuters reported.

"Our system is not optimized for generation of an entire brain and that was not at all our goal. Our major goal was to analyze the development of human brain (tissue) and generate a model system we can use to transfer knowledge from animal models to a human setting," Juergen Knoblich of Austria's Institute of Molecular Biotechnology told reporters. "This is one of the cases where size doesn't really matter."

Knoblich said growing a larger, more functional brain in the lad is not a goal of their research, the Telegraph reported. 

Regarding possible advancement of understanding neurological diseases, Knoblich said the research team was able to model microcephaly, or abnormal smallness of the head.

"But ultimately we'd like to move to more common disorders like schizophrenia or autism. We are confident that we might be able to model some of these defects," Knoblich said, according to The Telegraph.

The research has received a round of applause, but Dean Burnett, lecturer in psychiatry at the University of Cardiff, issued a word of caution not to overestimate the impact of the research.

"The human brain is the most complex thing in the known universe and has a frighteningly elaborate number of connections and interactions, both between its numerous subdivisions and the body in general," he said, according to Reuters.

"Saying you can replicate the workings of the brain with some tissue in a dish in a lab is like inventing the first abacus and saying you can use it to run the latest version of Microsoft Windows; there is a connection there, but we're a long way from that sort of application yet."