Binocular Vision Assessment

Vision is a very complex process that serves as our dominant sense. In fact, 80% or more of classroom learning occurs through the visual system. While being able to see 20/20 is important, it is only a small portion of overall visual performance. In addition to seeing clearly in the distance, one must have an efficient visual system with the ability to sustain clear, comfortable, single-image vision while scanning and interpreting the visual environment.


An inefficient visual system can result in a number of symptoms, including:

  • Blurred vision
  • Difficulties performing visual tasks (such as reading or computer work)

  • Double vision

  • Eye strain

  • Fatigue

  • Poor working memory

  • Processing speed deficits

  • Tracking difficulties


Unfortunately, the eye chart fails to identify many vision conditions that impact daily visual functioning. Vision conditions that affect one's visual performance include:

  • Accommodative dysfunction (eye focusing deficits)

  • Binocular vision dysfunction (difficulties with eye teaming - including strabismus)

  • Oculomotor dysfunction (eye tracking deficits)

  • Prolonged visual processing speed (slow to extract visual information)

  • Visual perceptual deficits (difficulties interpreting visual information)


A Binocular Vision Assessment with Advanced Vision Therapy Center is specifically designed to assess several visual skills that are typically overlooked during a routine eye exam. Several areas of visual performance will be evaluated using age-normed, standardized tests. This allows the doctor to identify visual deficits in a developing child as well as adults. The information gathered during the Binocular Vision Assessment is used by our team to identify areas of visual deficits in order to develop a customized treatment plan for improvement. 

Who Should Have a Binocular Vision Assessment?

A Binocular Vision Assessment is designed for both children and adults.



A Binocular Vision Assessment is recommended for children who struggle with visual tasks or who are symptomatic. The types of vision conditions identified during a Binocular Vision Assessment can affect both academic and athletic performance. It is estimated that 1 in 4 children have a vision problem significant enough to affect academic performance. This occurs because the child has difficulties efficiently taking in and interpreting visual information. In the classroom, vision conditions commonly affect reading, computer or other screen-time activities, and taking notes from the board. These tasks are extremely visually-demanding and require efficient eye tracking, eye teaming and eye focusing.


Symptoms of these vision conditions vary greatly. An underlying vision problem should be suspected by the parents and teacher if a child complains of:

  • Blurred or fluctuating vision

  • Double vision (even intermittent)

  • Eye strain, discomfort or soreness

  • Headaches after visual tasks

  • Visual fatigue

  • Words moving or floating on the page


Not all children voice complaints about their visual performance (many think how they see is 'normal'). Parents and teachers should look for the signs of an underlying vision problem:

  • Abnormal posture during near tasks (tilting or turning the head, leaning very close to the page, constant moving and re-positioning while working)

  • Avoidance of visual tasks, such as reading (would rather be 'read to' or refuses to read)

  • Covering or closing one eye (especially while reading)

  • Difficulties completing visual tasks (reading, taking notes, etc) in the time allowed

  • Drastic improvement with verbal tasks as compared to visual tasks

  • Frequent blinking

  • Skipping or re-reading words or lines of text

  • Squinting

  • Use of a finger (or line guide) to keep place while reading



Children do not grow out of the types of vision conditions identified during a Binocular Vision Assessment. As adults, they continue to experience the same symptoms as they did as children (blurred or fluctuating vision, double vision, eye strain or headaches). Many have found ways to compensate for their visual conditions; often by avoiding or limiting visual tasks. Others have accepted their visual limitations as 'normal for them'.


A Binocular Vision Assessment should be performed for adults with symptoms such as:

  • Blurred or fluctuating vision despite correction with glasses or contacts

  • Difficulties with 3D movies or TV (poor depth perception, discomfort, nausea)

  • Double vision (even intermittent)

  • Eye strain or discomfort with visual tasks (such as reading or computer work)

  • Headaches following reading, computer work or time on electronic devices

  • Visual fatigue

Why Have a Binocular Vision Assessment?

A Binocular Vision Assessment allows our team to identify several vision conditions often missed during a typical eye exam or vision screening. These vision conditions include: accommodative dysfunction (eye focusing deficits), binocular vision dysfunction (difficulties with eye teaming - including strabismus), oculomotor dysfunction (eye tracking deficits), visual perceptual deficits (difficulties interpreting visual information) and prolonged visual processing speed (slow to extract visual information).


Vision is a critical component to learning and most tasks of daily life. Undiagnosed vision conditions can impede academic success or one's ability to use their eyes comfortably and efficiently during work and hobbies. Identifying a vision problem allows a treatment plan to be put in place to effectively remove visual barriers to success.

Which Visual Skills are Evalauted During a Binocular Vision Assessment?

Our team evaluates several aspects of visual function during a Binocular Vision Assessment using age-normed, standardized testing. Based on the results, our doctors will prescribe an individualized treatment plan. Skills tested include:

  • Accommodation (eye focusing skills): The strength, flexibility, and accuracy of the eye focusing system is evaluated. Deficits in accommodation result in blurry vision during near work, blurry vision when transitioning from near to distance tasks (such as copying notes from the board in school), and eye strain or fatigue. Our doctors assess every aspect of the accommodative system and compare the results against age-based norms to identify deficits and prescribe the most appropriate treatment plan.

  • Depth Perception (3D vision): Often called “3D vision”, depth perception is dependent on the ability to use both eyes together at an optimum performance level. Deficiencies in depth perception can result in a lack of 3D vision or headaches and eye strain during 3D movies. There are multiple types of depth perception, all of which are assessed by our doctors during a binocular vision assessment.

  • Fusion: Fusion is the ability to use both eyes together. When an individual has a fusion deficit, they will either see double or the brain will adapt and suppress (or ignore) one of the eyes. Suppression can happen 100% of the time or intermittently, depending on the cause of fusion deficit. Our doctors evaluate your ability to use both eyes together in a variety of settings (for example at near versus distance) to determine if any fusion deficits are present. Depending on the cause of the fusion deficit, the doctor will design a customized treatment plan to eliminate the double vision and improve your ability to use both eyes together.

  • Ocular Motility (eye movements): The quality of your eye movements is related to the neural connections to the brain as well as the integrity of the eye muscles themselves. When evaluated by a residency trained eyecare provider, eye movements can be used to determine the presence of central nervous system dysfunction (such as that arising from tumors, inflammation, or neurological conditions). Additionally, ocular motility testing allows our doctors to evaluate eye tracking skills that are used during reading.

  • Ocular Posture (resting position): Ocular posture, or the resting position of the two eyes, is evaluated to determine the presence or absence of strabismus(eye turn). Eye position is also related to headaches, eyestrain, fatigue, and double vision. Assessment of ocular posture allows our doctors to determine the cause of any abnormal resting position and prescribe the most appropriate treatment plan.

  • Presence of Conditions That Affect Binocular Vision Function: There are several conditions that affect binocular vision function. Some of these conditions are ocular (such as amblyopia, strabismus, cataracts, glaucoma, and several other ocular diseases) while others are systemic (such as diabetes, stroke, thyroid dysfunction, autism, and cerebral palsy to name a few). Our doctors work with your other health care providers to ensure a multi-disciplinary team approach to your overall care.

  • Vergence (eye teaming): The strength and flexibility of the eye teaming system is evaluated. Deficits in eye teaming result in double vision, eyestrain, fatigue, headaches, or dizziness. Our doctors assess all aspects of eye teaming and compare them to age-based norms to determine the most appropriate treatment plan to improve eye teaming abilities.

  • Visual Acuity: How clearly you see is the foundation of a strong binocular vision system. If you do not see equally out of each eye it has the potential to affect eye teaming. Should you not see 20/20 out of each eye, our doctors will determine the cause of your reduced vision and the effect on binocular vision function.

  • Processing Speed: This is a measure of how quickly you process visual information. Deficiencies in processing speed will result in delayed reaction time (such as during driving or sports) or difficulties finishing timed tests, class assignments, or homework in a timely manner.

  • Spatial Awareness/Planning: This perceptual skill allows one to know right from left,orient themselves in space, and determine proper orientation of letters and numbers. Difficulties with spatial awareness and planning results in letter or number reversals, sloppy handwriting, misalignment of numbers in math problems, and other challenges with judging distances or directions.

  • Visual Integration: The integration of visual information with the other senses is critical. Making sense of your world relies on all of the senses working harmoniously. The integration of visual and fine motor skills is important for handwriting just as the integration of the auditory and visual systems is important for learning in the classroom. Advanced Vision Therapy Center works with other professionals (such as occupational therapists and speech/language pathologists) to coordinate therapy goals.

  • Visual Perception: This group of skills includes visual discrimination (determining likeness), spatial relations (determining differences), form constancy (determining sameness even when changed in size or orientation), visual memory, visual sequential memory, figure-ground (extracting valuable information from the background), and visual closure (ability to put the pieces together to form the whole). These perceptual skills are essential for academic success and learning.

  • Working Memory: This perceptual skill is critical for the acquisition of new material and concepts. Deficits in working memory can result in challenges learning new concepts; such as spelling. Those who struggle with working memory often find that no matter how hard (or how long) they try, the desired results are not achieved.

When Should a Binocular Vision Assessment be Performed?

A Binocular Vision Assessment should be performed as soon as concern arises from the eye doctor, the teacher, therapists who work with the child, the parents of the child or the individual themselves. While binocular vision conditions can be successfully treated in both children and adults, it is ideal to treat these vision conditions as early as possible. Early diagnosis and intervention allows a child to reach their full potential.


Unfortunately, vision conditions often go undiagnosed or are misdiagnosed (vision conditions are commonly mistaken for ADHD and dyslexia). Children with undiagnosed vision conditions often struggle in school. 80% or more of classroom learning occurs through the visual system. Visual deficits put a child at a huge disadvantage and prevent them from performing to their potential. When a child struggles in school, it is important to schedule a Binocular Vision Assessment to rule out a visual component to their struggles. Classroom tasks, such as reading or taking notes, rely on an efficient visual system. One of the early stages of intervention should be to treat any vision conditions that are present. Extra help with reading, tutors and fluency programs will not solve underlying vision conditions. You must first ensure that the child sees the book with clear, comfortable, single vision before asking them to read with greater fluency and comprehension. Image how difficult it would be to read if the text became blurry, split into two or moved on the page. 

Binocular Vision Assessments do not Require a Referral

If you suspect binocular vision deficits with yourself or someone you know, call Advanced Vision Therapy Center (208)377-1310 to schedule an appointment.

Improvement Starts Here

With over 25 years of proven success, you can trust Advanced Vision Therapy Center to provide the care you need.

Our Clinical Director is Idaho's only residency trained optometrist in vision therapy and neuro-optometry and is a Fellow of the American Academy of Optometry.  His residency at University of California, Berkeley means he has the expertise and experience to treat even the most complex cases.

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Contact Us

7960 W. Rifleman Street, #155
Boise , Idaho , 83704 USA
Phone:  208-377-1310
Fax:  208-321-1952