We’ve discussed eye tracking’s use in researching Alzheimer’s and autism, as well as its functions in assistive technology for individuals with multiple sclerosis. However, there is much more that eye tracking technology could do in the realm of auto-immune diseases, mental disorders, and disabilities than researchers may be aware of.
Eye movement is closely linked to the central nervous system. Because of this, disorders and diseases that affect the parts of the brain that control the nervous system also affect the way the eyes move. Recent research has shown that certain diseases, disorders, or conditions move the eyes in separate ways, which can indicate to researchers or doctors which part of the brain is damaged.
For example, people infected with AIDS can sometimes contract a disorder called AIDS Dementia Complex, or ADC. Much like normal dementia, ADC affects a person’s cognition, behavior, motor skills, and mood. ADC also affects the smooth pursuit movements of the eyes. Patients infected with HIV-1 may have smooth pursuit impairments before the onset of other, more detrimental symptoms. Eye tracking can be a way to detect these changes in eye movements and is less invasive than an MRI or a lumbar puncture. It also allows for the patient to have constant, day-to-day monitoring.
Another condition that leaves a unique eye-pattern is dyslexia. Children with dyslexia exhibit longer fixations and increased regressions while reading than do children without dyslexia, though researchers argue if it is the abnormal eye movements that lead to dyslexia or dyslexia leading to the eye movements. Studies have also shown a correlation between abnormal saccades and reading disabilities.
One disorder that has had researchers studying eye-movements for years is schizophrenia, and it is still an active research field. Schizophrenia is proven to impair smooth pursuit and increase saccade frequency, particularly catch-up saccades during smooth pursuit. These studies also believe that this kind of smooth pursuit impairment may be a promising indicator for the predisposition for schizophrenia.
There are many other conditions that directly affect the movements of the eyes, such as the above-mentioned Alzheimer’s, autism, and multiple sclerosis, as well as being under the influence of a variety of drugs, such as alcohol, cocaine and heroin. These conditions open more unique outlets for eye tracking technology. With it, it is possible for physicians, researchers, and psychologists to revolutionize the way their patients are seen and treated for disorders that were, up until recently, harder to diagnose and treat.
Vidal, Melodie; Turner, Jayson; Bulling, Andreas; Gellerson, Hans (2011). Wearable eye tracking for mental health monitoring. Computer Communications.