minibrain

A minibrain is a small, simplified neural network grown in vitro from neural tissue or stem cell–derived neurons. Usually cultured on a flat substrate and sometimes integrated with microelectrode arrays, these networks can generate spontaneous activity and controlled responses suitable for studying basic neural dynamics.

Minibrains serve as experimental models to investigate how neural circuits develop, form synaptic connections, and exhibit plasticity. Researchers record activity with microelectrode arrays or observe calcium signaling, and may use optogenetics or pharmacology to perturb the network. Studies often explore learning rules and how architecture influences dynamics.

Cell sources include embryonic or neonatal rodent tissue or human pluripotent stem cell–derived neurons. Cells are grown with supportive glia and growth factors, sometimes on patterned substrates to guide connectivity. The term minibrain is informal; in scientific contexts these are usually described as neuronal cultures, engineered networks, or brain-on-a-chip systems. They are distinct from brain organoids, which aim to resemble 3D brain structure more closely.

Applications include modeling development and disease-related changes in connectivity, screening drugs that affect network activity, and studying fundamental mechanisms of network dynamics in a controlled setting. While informative, they are simplifications of brain tissue and findings may not generalize to intact systems.

Limitations include small size, simplified circuitry, absence of vascularization and full brain architecture, variability between preparations, and potential ethical considerations when using human-derived cells. Nonetheless, minibrains provide a versatile tool for neuroscience research and education.