In this blog, we are summarizing the six core visual skills that AmblyoPlay is targeting to improve. By strengthening the fundamental visual skills, we can address a wide range of vision issues, such as amblyopia, strabismus, convergence insufficiency, double vision, etc. We outline the characteristics of each visual skill and the role it has in one’s vision health. There are also some symptoms mentioned that may help you recognize any anomalies.
Convergence
Convergence insufficiency happens when eyes do not work as a team and cannot converge efficiently. In other words, the eyes point behind an object rather than directly at it. Individuals with convergence insufficiency have problems maintaining binocular vision when looking at near objects, which affects their everyday activities. While the number of people with convergence problems is far from low (up to 15 %), we still don’t completely understand why convergence insufficiency ensues. Luckily, convergence insufficiency can be treated even later in life, and adults who perform eye exercises are able to achieve very high levels of improvements. Convergence excess refers to when the eyes point in front of an object than directly at it. If it is insufficient, one will experience discomfort and eyestrain when performing near activities such as writing or reading. Sometimes people can also experience headaches, fatigue and tension that often result in reading problems.
Divergence
It is the opposite of converge and means simultaneous outward movement of both eyes away from each other when looking at the object in distance. Divergence insufficiency is a condition of eye misalignment when eyes can not diverge properly, resulting in pointing in front of the object rather than at it. Another condition is divergence excess when the two eyes point behind the object rather than directly at it. The symptoms include double vision when looking at distance, wandering eye, headaches, and tired eyes.
Depth
It refers to the ability to discern whether objects are closer or further away in relation to one another and to see the world as three-dimensional. Depth perception is one of the most important visual skills. Binocular vision, commonly referred to as stereopsis, is a prerequisite for depth perception. However, depth impairment definitely has an impact on life. It can decrease a kid’s ability to learn. Furthermore, there is difficulty driving and navigating the appropriate road. For sports professionals, the poor depth prevents the development of their full potential. It also has an effect on career development as it prevents you from obtaining a position requiring strong depth perception skills.
Alignment
To achieve binocular vision, the eyes must be aligned. Eye alignment refers to looking in the same direction and focusing on the same object. If not, eye alignment problems occur, such as strabismus and amblyopia. We can check alignment using a torch, pay attention for abnormal head posture, do the cover test, and test ocular movements and double vision.
Recognition
Recognition refers to the ability to track an object when it moves across the vision field. It is one of the core visual skills that are needed for good vision in everyday life. Benefits of recognition training are observed in the most profound way in the outdoor activities.
Movement
Eye movements help stabilize images on the retina, enabling clear vision even while the subjects and the person are moving. Generally, there are four types of eye movement:
– Saccades: Saccades are quick eye movements when the focus of fixation rapidly shifts. For instance, they can be as little as the movements performed when reading or as large as those made while looking around a room. Saccades are also the rapid eye movements that take place during a critical stage of sleep.
– Smooth pursuit movements: These are significantly slower tracking movements of the eyes. Such movements are controlled voluntarily. The observer has the option to monitor a moving stimulus or not.
– Vergence movements: Vergence movements align the fovea of each eye with targets located at different distances from the observer.
– Vestibulo-ocular movements: Vestibulo-ocular movements balance out head movements by stabilizing the eyes’ position in relation to the outside world.
In conclusion, all the visual skills described are crucial for an overall vision health. If any of these visual skills are decreased, problems for a person occur. Luckily, many eyecare digital solutions exits, including AmblyoPlay to treat variety of vision condition.
Sources:
1. Luna, B., Velanova, K., & Geier, C. F. (2008). Development of eye-movement control. Brain and Cognition, 68(3), 293–308. https://doi.org/10.1016/j.bandc.2008.08.019
2. Purves D, Augustine GJ, Fitzpatrick D, et al., editors. Neuroscience. 2nd edition. Sunderland (MA): Sinauer Associates; 2001. Types of Eye Movements and Their Functions. Available from: https://www.ncbi.nlm.nih.gov/books/NBK10991/