A novel method for detecting Alzheimer’s disease at an early stage is gaining attention.
Researchers have found that subtle changes in eye movement, particularly a type of movement known as saccades, could serve as an early indicator of Alzheimer’s. The innovation lies in using a device that listens to these movements through microphones placed in the ears, potentially offering a simple and cost-effective way to monitor cognitive health.
Saccades are quick, involuntary eye movements that occur when we shift our focus from one point to another. For instance, when reading, the eyes make rapid jumps from word to word. In healthy individuals, these movements are fast and precise, but in those with Alzheimer’s disease, they tend to become slower and less accurate. This change is one of the earliest signs of cognitive decline in Alzheimer’s patients, though it is subtle at first, typically measured in milliseconds.
Traditionally, detecting abnormalities in saccadic eye movements requires specialized eye-tracking equipment, which is expensive and not always accessible. However, researchers from Dartmouth College and the École de Technologie Supérieure in Canada have developed a new approach using an in-ear device called a “hearable.” This device, which features sensitive microphones, captures vibrations caused by eye movements, even those as small as the saccades. While these vibrations are usually imperceptible to the human ear, the hearable can detect them and potentially use this information to help diagnose Alzheimer’s earlier.
The researchers, led by electrical engineer Rachel Bouserhal and neuroscientist Chris Niemczak, plan to test this technique on a group of 35 Alzheimer’s patients and 35 healthy individuals. They hope that this method will not only help in diagnosing Alzheimer’s more efficiently but also provide a tool for tracking the disease’s progression over time. Furthermore, while the current study focuses on Alzheimer’s, the same principles could be applied to other neurodegenerative diseases in the future.
Eye movement patterns, including saccadic latency, have been linked to the early stages of Alzheimer’s disease. In fact, a 2022 study by Loughborough University found that abnormalities in eye movements could reliably predict dementia in individuals with mild cognitive impairment. However, not everyone with altered saccadic patterns will necessarily develop Alzheimer’s, meaning these changes are a potential but not definitive sign of the disease.
The development of hearable devices for continuous monitoring represents a significant step toward making Alzheimer’s diagnosis more accessible. Traditional eye-tracking devices, though effective, are not widely available and can be cost-prohibitive. The hearable device could offer a portable, affordable alternative for individuals in clinical settings or even at home, potentially allowing for earlier detection of Alzheimer’s and other diseases.
Alzheimer’s disease currently affects millions of people worldwide, and with an aging population, the number of cases is expected to rise. Early diagnosis is critical because while there is no cure for Alzheimer’s, treatments can help manage symptoms and delay the disease’s progression. Researchers hope that with tools like the hearable device, they can improve early detection and, ultimately, the quality of life for those affected by the disease.
In addition to Alzheimer’s, researchers envision that the technology could be expanded to monitor other conditions, such as Parkinson’s disease, that also affect eye movement. The ability to track symptoms through in-ear sensors could eventually offer a low-cost, non-invasive method for monitoring multiple neurological disorders, providing valuable data for both patients and doctors.
With input from the Daily Mail and Science Alert.
