Autism Spectrum Disorders (ASD) are a group of conditions that may affect a person’s social interaction, communication, gastrointestinal system, motor coordination, and several other aspects of life. ASD is generally diagnosed around 2-3 years of age and is 4-5x more prevalent in boys than girls. The CDC estimates that 1 in every 88 children is diagnosed with an Autism Spectrum Disorder.
The causes of ASD are still being researched at this time. Researchers have determined that ASD is a combination of a genetic predilection as well as an environmental cause. The environmental causes have yet to be determined but it is hypothesized that they are most likely to affect the individual while they are in utero or during the birthing process. Researchers have determined that ASD is not caused from immunizations, which was previously hypothesized.
ASD is a unique condition because it includes a wide variety of ways it is expressed. No one individual with ASD is the same as another individual with ASD. Individuals with ASD are also prone to having ocular and visual conditions. As previously mentioned, ASD has a multitude of systemic presentations, and this variety holds true for the visual system as well. Patients with ASD demonstrate a variety of vision conditions that include eye teaming, eye focusing, and visual perceptual deficits. Some people may have a hyperactive visual system, which makes colorful and abrupt visual stimuli disturbing. Others may demonstrate a hypoactive visual system and they are drawn to colorful and bright visual stimuli because it stimulates their visual world.
Autism Spectrum Disorder has several effects on the visual system, which include:
Significant refractive errors (farsightedness / nearsightedness)
- Uncorrected refractive error affects how a person interacts with their world.
- Uncorrected farsightedness makes it extremely difficult to keep objects clear at near. In fact, if the farsighted prescription is high enough it can cause blurry vision at both distance and near.
- Uncorrected nearsightedness results in blurry vision at distance. If the prescription is high enough, the person will also experience blurry vision at a typical reading or computer distance. To compensate for this blurry vision, you will often see a person with uncorrected nearsightedness hold reading material closer than normal.
- When significant amounts of farsightedness, nearsightedness, and astigmatism go uncorrected, amblyopia can result. Amblyopia is a condition where vision is reduced in an eye that otherwise appears healthy. Fortunately this condition is treatable.
- Strabismus, commonly referred to as "crossed" or "wandering eyes", occurs when one or both eyes turns in or out, up or down. The condition is caused by the brain's inability to coordinate both eyes simultaneously. The brain is the master control center of vision, and somewhere early in a child's vision development, the brain failed to develop "binocularity," or the ability to use both eyes at the same time. It is important that strabismus receive prompt treatment. Children do not outgrow crossed eyes, and the condition can worsen over time.
- Because the brain has not learned to align the eyes and use them together, each eye aims independently of the other. In other words, both eyes do not point at the same place at the same time. When each eye is looking at a different place, the brain receives two different "pictures". This would normally result in double vision. However, these children's brains learn to protect themselves from seeing double by suppressing, or "turning off" the crossed eye. The brain refuses to receive the visual input from the turned eye; children with a crossed or wandering eye only see out of one eye at a time.
- There are multiple treatment options for the treatment of strabismus. Some of these approaches are designed to physically reduced the magnitude of the eye turn so that it is less noticeable (even if the person continues to see double or suppress an eye), while others are designed to both improve the appearance of the eye turn and improve the binocular vision abilities; allowing for clear, comfortable, three-dimensional, vision with both eyes. Our residency-trained doctors can discuss all treatment options for strabismus and help you decide which approach is best.
Amblyopia (Lazy Eye)
- Amblyopia is a condition that results in reduced clarity of vision in an otherwise healthy eye. The most common causes of amblyopia include uncorrected refractive error and certain types of eye turns. If amblyopia is suspected, the best first step is to have the child examined by a residency-trained pediatric optometrist. Amblyopia is a treatable condition, with glasses often times being the first step. In the capable hands of an optometrist with residency training in the area of amblyopia, a treatment plan can be developed to improve the reduced vision.
Hyperactive Visual System
- Focusing on tiny pieces of dust/particles
- Dislike of the dark and bright lights
- Dislike of sharp flashes of light
- Looking down most of the time
- Covering/closing eyes at bright lights
Hypoactive Visual System
- Attracted to light
- Looking intensely at objects or people
- Moving fingers in front of eyes
- Fascination with reflections and/or brightly colored objects
- Running hands around the edges of objects
Preferred fixation in extreme lateral gaze with head turned in opposite direction
- Helps regulate excessive amounts of local detailed information
Fixation abnormalities (ability to keep eyes focused on a target)
- Poor ability to keep one’s eyes “locked on” to a target can create many difficulties. In school, fixation abnormalities will make it extremely difficult to take in visual information.
- Fixation abnormalities will make it difficult to copy information from the board, read, or complete other classroom assignments.
Saccadic abnormalities (ability to jump from target to target)
- Saccades are coordinated jumps of the eyes (think of shifting your attention quickly from the television to your phone when someone calls. These eye jumps are essential for most visual tasks. In school, saccades allow a person to copy information from the board and read efficiently. People with saccadic abnormalities will notice that they often skip lines or re-read lines of text.
Pursuit abnormalities (ability to smoothly follow a target)
- Pursuits are smooth eye tracking movements. We use pursuits when following slow moving objects. Smooth eye movements are necessary to be a smooth and fluid reader.
- Excel with visual search tasks
- Excel on block design sub-test (IQ test battery)
- Difficulty in a range of color discrimination tasks (Results similar to that of a child 3 years younger)
- Increased stress response with person looking straight at them
- Difficulty with the ability to process the eye region of the face
- Prefer to shift attention from object-to-object as opposed to person-to-person
- Difficulty recognizing complex facial expressions