The scientific community is in danger of overstepping (or may have already breached) its ethical responsibilities in a rush to study and understand the mysteries of the brain via experimentation with artificially grown substitutes, researchers warn.
But while these lab-grown analogues grown from stem cells aren’t technically considered human or animal organs, they’re becoming functionally close enough to warrant serious ethical concerns – if not an outright ban on their use, according to some neuroscientists.
In a presentation this week at the world’s largest gathering of neuroscientists, a team led by researchers from the Green Neuroscience Laboratory in San Diego made the case for why there is an “urgent need” for scientists to develop a framework of criteria that stipulates what ‘sentience’ is, so that future research using mini-brains and stem cell cultures can be bound by a developed set of ethical rules.
“The compositional and causal features in these cultures are – by design – often very similar to naturally occurring neural substrates,” the team explains in their abstract.
“Recent developments in organoid research also entail that the anatomical substrates are now approaching local network organisation and larger structures found in sentient animals.”
There’s a lot of evidence to support this. In recent years, scientists have promoted mini-brains as an economical and practical alternative to animal testing, and advancements in nurturing stem cells are helping scientists figure out how to mimic the complex neural subtypes of human brain tissue.
Mini-brains grown in dishes have enabled researchers to probe the differences between humans and chimpanzees, and the rapid pace with which the field is evolving is almost scary.
In March, scientists grew a mini-brain – said to be roughly analogous in complexity to a human foetal brain at 12 to 13 weeks – and, in the context of their model experiment, it spontaneously connected itself to a nearby spinal cord and muscle tissue.
A few months later, in a separate experiment, researchers detected electrical activity exhibited by organoids that looked startlingly similar to human brain waves.
While the scientific teams behind these incredible accomplishments are usually quick to observe that the organoids we’re capable of developing today are far removed from showing the neural sophistication of human and animal brains, Ohayon and his team’s computational models suggest we’re getting awfully close to growing sentient brains in a dish.