United States: Scientists have discovered a new way to help detect Alzheimer’s disease early by listening to the movements of a person’s eyes. This method uses microphones placed in the ears to detect changes in eye movement, called saccades. When someone has Alzheimer’s, their eye movements become slower and less accurate, and this could be one of the first signs of the disease.
As reported by the sciencealert.com, the sort of equipment that would likely be needed to quantify saccades may complicate the analysis but ambulatory microphones to capture the normal sounds of the body probably can be used to measure the motions instead.
A team from École de Technology Supérieure in Canada, led by electrical engineer, Rachel Bouserhal, and neuroscience student, Chris Niemczak of Dartmouth College in the US plan to use the technique on 35 Alzheimer’s patients to establish how effective it is.
‘Eye movements are interesting because they are among the fastest and most accurate movements in the human body so they depend on good motor control and good cognition,’ explains electrical engineer Arian Shamei of École de Technologie Supérieure.
In order to build up a coherent picture of an image or scene, the eyes jump rapidly and in a co-ordinate manner from point to point in the target area, taking about tens of milliseconds on each point.
It is common but unless you have paid particular attention to the nooks and crannies of people’s face as they read or if you have watched them as they proceed through the REM stage of sleep then you may not have come across them.
These are saccades, and for a patient with Alzheimer’s, the tiny motions evolve to be slower and less accurate as motility deteriorates. The symptom is hardly noticeable at the time, the wait is fifteen milliseconds, but it worsens over time or with progression of the disease.
It was hypothesized that saccadic latency can be used as a diagnostic instrument of Alzheimer’s disease one that is cheap, painless, does not require any prior literacy and is not invasive. But eye-tracking equipment is not always portable or accessible, so the researchers thought another option might work: a hearable, which is a special type of technology.
”It is an earpiece with in-ear microphones that captures physiological signals from the body,” says electrical engineer Miriam Boutros of École de Technologie Supérieure.
Our goal is to develop health-monitoring algorithms for the hearables who are capable fo continuous long-term monitoring and early disease detection.