FIGURE 1.

The continuum of moral significance in organoid research. Organoids vary widely in their complexity, so it becomes important to consider if, and where, different organoids fall on this continuum of moral significance. For example, an organoid using a protocol, which generates a cerebral organoid with varying populations of cells from different brain regions, would likely be lower on the hierarchy than a region-specific organoid, which contains more mature organization. Moving up the pyramid, co-culturing region-specific organoids creates reciprocal connections that begin to form primitive circuits. Connectoids offer even further maturation of function. The addition of more region-specific organoids, non-neural cell types like endothelial cells or microglia, external perfusion systems, and bioengineering will allow organoids to grow in size, cell number, and synaptic density. This will continue to increase the complexity and thus the moral significance of such organoids.