Mini-brains may already be sentient and suffering, scientists warn

Author: Stephen Johnson

Neuroscientists are “perilously close” to crossing serious ethical lines by experimenting with mini-brains that might be complex enough to feel pain. In fact, experiments with mini-brains (also called organoids) might have already crossed those lines.

“If there’s even a possibility of the organoid being sentient, we could be crossing that line,” Elan Ohayon, the director of the Green Neuroscience Laboratory in San Diego, California, told The Guardian. “We don’t want people doing research where there is potential for something to suffer.”

On Monday, Ohayon and his colleagues presented a computational study at Neuroscience 2019, the world’s largest annual meeting of neuroscientists. The study aimed to establish guidelines for scientists to determine when exactly a mini-brain develops consciousness.

“Assessment informed by the models and associated dynamics suggests that current organoid research is perilously close to crossing this ethical Rubicon and may have already done so,” the paper states. “Despite the field’s perception that the complexity and diversity of cellular elements in vivo remains unmatched by today’s organoids, current cultures are already isomorphic to sentient brain structure and activity in critical domains and so may be capable of supporting sentient activity and behavior.”

Stand-ins for human brains

Mini-brains are tiny lumps of tissue made from stem cells that are capable of generating rudimentary neural activity, and researchers use them in neuroscience experiments. The main benefit of mini-brains is that scientists can conduct important research that sheds light on the human brain all without having to use actual human or animal brains.

As Big Think’s Robby Berman noted in March, mini-brains are relatively rudimentary. The most advanced organoid possesses a couple million neurons — twice that of a cockroach, but far fewer than an adult zebrafish. The human brain, meanwhile, has some 100 billion neurons. But mini-brains are becoming more complex.

This story originally appeared at Big Think.