Organoids are 3D lab-grown structures from stem cells that mimic real organs, aiding biomedical research, drug testing, and personalized medicine. Cerebral organoids (mini-brains) show neural activity similar to a fetal brain, raising ethical concerns about potential sentience. Techniques like the Perturbational Complexity Index, based on Integrated Information Theory, could measure consciousness in these organoids, as done for brain-injured patients. If sentience is detected, ethical debates on their use in research and practice become necessary.
The mind-body problem—how consciousness arises from brain processes—has long been considered a philosophical puzzle but is now being tackled empirically. This review describes progress since Crick and Koch (1998) proposed searching for the neural correlates of consciousness (NCC). It covers content-specific NCCs, which link particular brain activity to specific experiences, and the full NCC, which supports entire conscious states. The authors discuss methodological advances for isolating conscious experience from enabling functions, suggest that reconsidering the frontal cortex's role may refine NCCs, advocate for objective brain-based measures of consciousness independent of sensory or executive processes, and show how animal studies reveal network phenomena relevant to consciousness mechanisms.