Understanding how the brain creates conscious experience remains one of science’s most difficult challenges. Brain scans and behavior studies have linked awareness to certain neural patterns, but those links rarely show cause and effect. Activity can appear alongside a conscious experience without actually producing it. A new paper argues that progress now depends on tools that can directly test which brain structures generate conscious perception. That argument comes from researchers at the Massachusetts Institute of Technology, the University of Florida, Brigham and Women’s Hospital, and Harvard Medical School. The team outlines how an emerging technology, transcranial focused ultrasound, could allow scientists to move beyond correlation and begin testing causality in healthy human brains. Their work appears in the journal Neuroscience and Biobehavioral Reviews. The authors include Daniel Freeman of MIT Lincoln Laboratory, Brian Odegaard of the University of Florida, Seung-Schik Yoo of Brigham and Women’s Hospital and Harvard Medical School, and Matthias Michel of MIT’s Department of Philosophy and Linguistics. Together, they describe the paper as a roadmap for using ultrasound to probe the biological …