Early and accurate diagnosis of dementia remains a major challenge. Standard approaches such as MRI and PET scans can provide valuable information about brain structure and function, but they are expensive, not always accessible, and often too expensive for repeated use.

A team of researchers in the UK has now demonstrated that a compact, noninvasive technology—broadband near-infrared spectroscopy (bNIRS)—may offer a new way to detect brain changes linked to Alzheimer’s disease, even in the early stages.

In this pilot study reported in the Journal of Biomedical Optics, scientists used bNIRS to monitor both blood oxygenation and brain metabolism in response to visual stimulation.