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Mini Brains In A Dish Grow Eye-Like Structures


Benjamin Taub


Benjamin Taub

Freelance Writer

Benjamin holds a Master's degree in anthropology from University College London and has worked in the fields of neuroscience research and mental health treatment.

Freelance Writer

Brain organoid with optic cups

Brain organoid with optic cups. Image: Elke Gabriel

Miniature brains created from stem cells have spontaneously sprouted embryonic eye-like structures called “optic cups,” according to a new study in the journal Cell Stem Cell.

While the resulting blobs may look like confused lychees, researchers hope to use them to learn about the early stages of eye development and gain new insights into the underpinnings of retinal disorders.


Stem cell-derived brain organoids are often used to study various aspects of neural development, although the challenge of creating mini-brains with other organs attached had until now not been overcome. After treating their organoids with certain compounds related to vitamin A, however, the study authors observed that optic cups began to appear on the surface of these tiny brains after around 30 days, becoming fully developed in 50 to 60 days.

The optic cup is the structure that gives rise to the retina and the majority of the eyeball, yet much remains unknown about the processes behind this development. Scientists have previously managed to grow isolated optic cups from stem cells, although such experiments failed to reveal how these nascent eye-like organs become integrated with the brain.

Crucially, therefore, the optic cups that appeared in this study developed several types of retinal cells that became organized into neuronal networks and displayed connectivity with other regions of the brain organoids, becoming fully integrated. As such, they displayed an ability to respond to light, allowing the researchers to observe some of the complex interactions mirroring those that occur between the eyes and brain of a developing embryo.

The optic cups took about 60 days to become fully developed. Image: Elke Gabriel

The study is also remarkable for what it reveals about the nature of stem cell-derived brain organoids. Previously, these structures had been considered highly chaotic tissues lacking a back or a front – yet the emergence of two symmetrically placed optic cups suggests that these mini-brains are in fact capable of self-patterning.


Importantly, researchers were able to reliably reproduce these findings, demonstrating that the spontaneous development of eye-like structures was not a random event. In total, they produced 314 separate mini-brains, 72 percent of which grew optic cups.

“Our work highlights the remarkable ability of brain organoids to generate primitive sensory structures that are light sensitive and harbor cell types similar to those found in the body,” explained study author Jay Gopalakrishnan in a statement.

 “These organoids can help to study brain-eye interactions during embryo development, model congenital retinal disorders, and generate patient-specific retinal cell types for personalized drug testing and transplantation therapies.”



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healthHealth and Medicine
  • tag
  • stem cells,

  • organs,

  • eyes,

  • brains,

  • organoids