Neuroscientists propose looking for the source of consciousness in the brainstem, not the cortex

Hypothesis: basic experience resides in subcortical structures

Neuroscientists Marshall Devor and Mark Baron have proposed looking for the source of the basic subjective sense of existence not in the cerebral cortex, but in the brainstem. Their theoretical work is published in the journal The Neuroscientist; as reported by Gazeta.Ru. The authors distinguish between the content of experience — for example, a visual image — and the sense of being a perceiving being: they consider the cortex important for complex information processing, but place the basic experience itself in ancient subcortical structures.

What the argument rests on

One line of argument concerns pain: the authors discuss cases in which extensive cortical damage did not eliminate pain experiences, whereas small lesions in certain areas of the upper brainstem could be accompanied by coma. Another part consists of experiments on rodents: injecting anesthetics into a small area of the upper brainstem produced signs of anesthesia, while destroying the narrowest area itself and more extensive damage to the surrounding zone produced different results. On this basis, the authors suggest that what matters is a network in the surrounding area, not a single 'switch' point. In their evolutionary model, the capacity to experience pain emerged in ancient vertebrates, while later systems made use of the already existing mechanism of subjective experience.

Context and limitations

This is a theoretical work, not the result of a new experiment: the conclusions rest on a reinterpretation of already known data on pain, anesthesia, and nervous system damage. Separately, Gazeta.Ru mentions an earlier report in which neuroscientists stated that emotions are a 'theater for others,' not what we actually feel; that publication goes beyond the new hypothesis and is cited by the outlet as related news.