Study shows decreased focus on internal facial features in AMD

WHY do age-related macular degeneration patients have trouble recognizing faces?

Unlike people with normal vision focus, those with AMD don't focus on "internal features" (the eyes, nose and mouth) when looking at the image of a face, according to the study "Abnormal Fixation in Individuals with AMD when Viewing an Image of a Face" by William Seiple, PhD, and colleagues of Lighthouse International, New York. Their findings appear n in the January issue of Optometry and Vision Science, official journal of the American Academy of Optometry. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.. They write, "Abnormal eye movement patterns and fixations may contribute to deficits in face perception in AMD patients."

Eye movements recorded
The researchers used a sophisticated technique called optical coherence tomography/scanning laser ophthalmoscopy (OCT-SLO) to examine the interior of the eye in nine patients with AMD. Age-related macular degeneration is the leading cause of vision loss in older adults. It causes gradual destruction of the macula, leading to blurring and loss of central vision.

Previous studies have suggested that people with AMD have difficulty perceiving faces. To evaluate the possible role of abnormal eye movements, Dr Seiple and colleagues used the OCT-SLO equipment to make microscopic movies of the interior of the eye (fundus, including the retina and macula) as the patients viewed one of the world's most famous faces: the Mona Lisa.

This technique allowed the researchers to record eye movements and where the patients looked (fixations) while looking at the face. They compared the findings in AMD patients to a control group of subjects with normal vision.