MIT researchers are exploring transcranial focused ultrasound, a noninvasive technology that can precisely stimulate deep regions of the brain, and in a new roadmap paper they explain how this method could finally let scientists test cause-and-effect in consciousness research, not just observe correlations. This noninvasive technology reaches deeper into the brain with greater resolution than techniques such as EEG and MRI, and works by sending acoustic waves through the skull to focus on areas of a few millimeters, allowing specific brain structures to be stimulated. The approach promises to bridge the gap between neural activity and actual experience. Freeman's team is planning experiments that start with the visual cortex and later move to higher-level regions, with the goal of connecting brain modulation to what someone actually experiences, not just what neurons do.
Finally, a way to ask the brain directly whether it's conscious, rather than asking it nicely.