After decades of research, scientists still struggle to explain how the brain produces consciousness and creates our thoughts and emotions. Researchers at MIT may be able to answer this fundamental question in the near future, through their discovery of a new brain imaging technology. Transcranial focused ultrasound (tFUS) utilizes sound waves to reach and activate deep areas in the brain without surgery. With direct manipulation of these regions, it could become possible to identify which specific neurons are responsible for conscious experiences.

Other brain scanning technologies, such as magnetic resonance imaging (MRI) and electroencephalography (EEG) , show brain activity patterns, but scientists can not link these signals to consciousness. They can observe brain regions becoming active when individuals feel certain emotions, but these scans do not provide enough evidence to prove that those regions produce conscious experience. This is where the tFUS technology comes in, sending acoustic waves through the skull to a precise area of the brain. The machine’s ability to target deep regions of the brain, such as subcortical structures , has made it possible to study neural pathways that were previously difficult to reach.

tFUS helps separate correlation from causation, and MIT researchers plan to use this emerging technology to explore various theories of consciousness. The cognitivist approach , a prevailing framework of consciousness, focuses on how the brain’s cognitive processes interact across networks in the frontal cortex. Another belief argues consciousness does not involve higher-level cognition, but from the activity in deeper subcortical regions . A focused ultrasound could allow scientists to target specific brain areas and investigate how those regions influence consciousness.

Researchers believe that studying vision and pain can provide helpful fundamental data for future experiments with tFUS technology. They can activate the visual cortex of the brain and observe whether this changes what the individual consciously interprets. Scientists are also intrigued by how innate reflexes allow people to withdraw from potentially harmful stimuli, such as pulling their hand away from a hot surface, often before consciously experiencing the pain.. Manipulating different regions of the brain with tFUS could help them test which brain areas are responsible for the particular conscious experience.

Although transcranial focused ultrasound is still an emerging technology , it could transform how scientists analyze consciousness. Researchers stress that they do not yet completely understand how useful or effective tFUS will be in addressing the theories of consciousness, and that in-depth experiments are necessary. Nonetheless, tFUS shows promise in its highly accurate method for stimulating deep brain activity and connecting this to the conscious experience. Considering all of this information, focused ultrasounds could bring the world closer to understanding one of the greatest scientific questions.