A new brain scanning system that shines tiny lights onto the head works just as well as magnetic brain scanner, researchers have revealed.

The new system requires wearers to don a ‘smart cap’. It works by detecting light transmitted through the head and capturing the dynamic changes in the colors of the brain tissue.

Researchers say the new optical approach is ideal for children and for patients with electronic implants, such as pacemakers, cochlear implants, and deep brain stimulators that are used to treat Parkinson’s disease.

The magnetic fields in magnetic resonance imaging (MRI) often disrupt either the function or safety of implanted electrical devices. Researchers have been developing the technology, called diffuse optical tomography (DOT), for more than 10 years, but the method had been limited to small regions of the brain.

The new dot instrument covers two-thirds of the head and for the first time can image brain processes taking place in multiple regions and brain networks such as those involved in language processing and self-reflection (daydreaming). ‘When the neuronal activity of a region in the brain increases, highly oxygenated blood flows to the parts of the brain doing more work, and we can detect that,’ said Joseph Culver of Washington University, who led the project.

It’s roughly akin to spotting the rush of blood to someone’s cheeks when they blush.’ The technique works by detecting light transmitted through the head and capturing the dynamic changes in the colors of the brain tissue.

Although DOT technology is now used in research settings, it has the potential to be helpful in many medical scenarios as a surrogate for functional MRI, the most commonly used imaging method for mapping human brain function. Functional MRI also tracks activity in the brain via changes in blood flow, and is used to diagnose and monitor brain disease and therapy.

Another commonly used method for mapping brain function is positron emission tomography (PET), which involves radiation exposure. 

Because DOT technology does not use radiation, multiple scans performed over time could be used to monitor the progress of patients treated for brain injuries, developmental disorders such as autism, neurodegenerative disorders such as Parkinson’s, and other diseases.

Unlike fMRI and PET, DOT technology is designed to be portable, so it could be used at a patient’s bedside or in the operating room. The researchers say DOT, could be used to learn more about how deep brain stimulation helps Parkinson’s patients, imaging the brain during social interactions, and studying what happens to the brain during general anesthesia and when the heart is temporarily stopped during cardiac surgery.

For the current study, published online in Nature Photonics, the researchers validated the performance of DOT by comparing its results to fMRI scans. Data was collected using the same subjects, and the DOT and fMRI images were aligned. They looked for Broca’s area, a key area of the frontal lobe used for language and speech production.