Consciousness is the most personal concept about reality and possibly the most mysterious phenomenon known. No reductionist framework has been developed to identify the precise neural mechanisms that give rise to it. Many experiments have difficulty distinguishing between consciousness experiences and the act of reporting what we have experienced, so it is difficult to know if the brain activity that we measure relates to consciousness or our other cognitive processes. Moreover, these experiments normally apply to humans and primates, neither of which can easily be described in terms of reductionist mechanisms.

This project, led by Nikhil Bhatla and Hillel Adesnik’s lab at UC Berkeley, applies a recently developed paradigm for consciousness analysis in the mouse. For the purpose of the experiment, we assume that mice are indeed conscious to some extent, and that the brain mechanisms that allow them to be conscious are close enough to humans that we can discover meaningful information. The project involves a blindsight model, where most of the brain works well enough that brain activity responds to light, but the mouse seems unconscious of what it ought to see. Blindsight is a useful phenomenon also studied in humans, where people respond to things they see, but seem unaware of those things and they can’t completely explain their responses.

The project will examine this mouse model to discover cell types and brain areas specifically required for the conscious component of vision but expendable for the unconscious component. This can’t be done in humans because no technology exists to examine individual cells so carefully.

If successful, these discoveries will help researchers identify what kinds of brain cells might be uniquely necessary for consciousness. It could therefore make progress on the Big Question of how the brain creates consciousness by identifying specific parts that make up the puzzle. Just as the discovery of the structure of DNA helped resolve some of the mystery surrounding the nature of life, similarly, these discoveries may form the foundation for a mechanistic analysis of consciousness.

The experiment will test the hypothesis that there will exist specific cellular types a the part of the brain that is required for vision (primary visual cortex) that support conscious vision. Such findings can lead to new questions that other researchers can build on to cover more ground. Findings from this project may provide new evidence that can be used to either support existing theories of consciousness, such as global neuronal workspace theory or integrated information theory, or form the basis for development of a new, empirically-grounded theory.