Dr. Rene Anand who led a team of scientists at Ohio State University claimed to have made a big breakthrough by developing the human brain of the size of a five-week fetus — the size of a pencil erasure, or about 4 x 6 mm. It is an organoid for which human skin cells were collected from an adult which were converted into stem cells ( pluripotent cells ) which can develop into any tissue. A specialized environment was provided to these stem cells to let them be the brain cells of different types. The differentiation is a matter of IPR. The whole process took 15 weeks.

To grow further, the cells would require a network of blood vessels sophisticated enough and an artificial heart. Such brain models enable scientists to study the functioning of the system and to serve as replacements to defective organs. Already in 2013, Vienna scientists at Institute of Molecular Biotechnology had used stem cells to grow a brain larger than the Ohio experiment. But it had much more immature structures. The Ohio brain, though small, resembles a full-sized brain in complexity; and carries 99 percent of the diverse cell types found in an adult brain. Dr. Anand is hopeful of developing the remaining 1 per cent of cells by continuing the experiment.

The organoid has no awareness. It is not connected to any sensory input organs. The ethical issues of consciousness and cognition are thus bypassed.

The brain would be used to study stresses caused by war. In future, neurological diseases and conditions can be studied. If backed by circulatory system, conditions such as stroke can be studied. The environmental toxins affecting the foetal development can be studied. In diagnostics, an organoid can be developed by taking skin cells of a patient and a personalized diagnosis can be made.

Ohio experiment has not so far been peer-reviewed and data has not been released for other scientists on account of patent issues.