The scientists ran an experiment with mice using ultrasound imaging to measure and record brain activity. The mice were shown visual stimuli, either an object or a scrambled image showing no distinct object. They found a small number of brain areas that fired especially when the mouse looked at objects. These areas were found in a brain region called the postsubiculum which specializes in keeping track of where the animal is facing at any given time. Each direction activates a specific cell in the postsubiculum. Objects in the mice’s vision increased the firing of the cell responsible for the direction in which the mouse was looking. They also inhibited cells responsible for directions where the mouse was not looking. Together, this activity reinforced the mouse’s perception of where it was relative to the object.

Diagnosing dementia early is challenging due to variability in symptoms and limited access to advanced imaging tools. In a pilot study, researchers tested broadband near-infrared spectroscopy (bNIRS), a portable and noninvasive neuromonitoring technology that measures both blood oxygenation and concentration of oxidized cytochrome c oxidase (oxCCO), a metabolic mitochondrial enzyme linked to Alzheimer’s disease. In this study, participants with mild cognitive impairment, early Alzheimer’s dementia, and healthy controls observed a visual stimulus while bNIRS recorded brain responses. Statistical analysis showed a strong correlation between derivatives of bNIRS signals and cognitive test scores, which weakened significantly when oxCCO metrics were excluded. These results suggest that bNIRS, particularly with its ability to measure oxCCO, could provide an accessible portable technique for diagnosing and monitoring dementia.