KNOWLEDGE BASE

Glossary of Terms

The ocu•vio glossary is our knowledge base on daily care for the visual comfort of the whole family. ocu•vio missions provide recreational support for good habits at home — fun, relaxation, and awareness in short, thoughtfully designed sessions. If your child is under the care of a specialist, always consult with the caregiver before choosing any home activities.

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20-20-20 Rule

The 20-20-20 rule is one of the most frequently cited and easily remembered standards of visual work hygiene worldwide: every 20 minutes of screen time, look at an object at least 20 feet away (about 6 meters) for a minimum of 20 seconds.

Accommodation of the Eye (Focusing Ability)

Accommodation is the eye's ability to automatically change focus depending on the distance of the viewed object — exactly like a camera lens adjusts focus between near and far objects, but in the eye, this happens without conscious control.

Accommodative Spasm

Accommodative spasm (spasm of accommodation, sometimes referred to as accommodative pseudomyopia) is a condition in which the ciliary muscle — the ring-shaped muscle surrounding the lens inside the eye — remains excessively and involuntarily tense for an extended period, instead of freely relaxing between episodes of near work.

Amblyopia (Lazy Eye)

Amblyopia is a condition in which vision in one eye develops more poorly than in the other, despite the absence of any visible structural defect in that eye — the brain, receiving a clearer signal from one eye for an extended period, gradually begins to favor it at the expense of the other, whose signal is increasingly suppressed at the cortical processing level.

Anisometropia

Anisometropia is a condition in which each eye has a different refractive error — one may be hyperopic, while the other sees normally, or both may have the same error but with distinctly different values.

Anti-Suppression Therapy

Anti-suppression therapy is a procedure aimed at breaking suppression — a mechanism in which the brain suppresses the image coming from one eye.

Art Therapy (Creative Expression Supporting Development)

Art therapy as a formalized field emerged in the mid-20th century independently in several locations: in the United States, the term and practice were developed by figures such as Margaret Naumburg and Edith Kramer, while in the United Kingdom, the term "art therapy" was coined by Adrian Hill, a painter who discovered the therapeutic value of drawing during his own recovery in a tuberculosis sanatorium in the 1940s and began to introduce it among other patients.

Astigmatism

Astigmatism is a refractive error resulting from an irregular shape of the cornea or lens of the eye — instead of a perfectly spherical surface, the curvature of the eye resembles the shape of a rugby ball, causing light rays to focus in more than one point.

Binocular Fusion

Binocular fusion is the brain's ability to combine two slightly different images — one from each eye — into a single, cohesive, non-doubled view.

Binocular Vision and Anaglyphs

Binocular vision is the brain's ability to combine two slightly different images — one from each eye — into one cohesive view that carries additional information: depth.

Blinking and Eye Comfort (Tear Film)

Each blink spreads a tear film across the surface of the eye — a thin, yet precisely structured protective layer composed of three cooperating layers.

Blue Light — Facts and Myths

Blue light is part of the visible spectrum with a wavelength of approximately 400–490 nanometers — the shortest and therefore most energetic among visible colors to the eye.

Convergence (Eye Convergence)

Convergence is the coordinated, inward movement of both eyeballs "toward the nose," which allows for a single, sharp image of an object located close to the face.

Convergence Insufficiency

Convergence insufficiency is difficulty keeping the eyes converged when looking at something up close.

Critical Period of Visual System Plasticity

The critical period is a time in a child's development when the connections in the brain's visual cortex are still susceptible to change based on the signals received from both eyes — thus, a time when uneven visual development can still be most effectively reversed.

Decompensation

Decompensation is the moment at which a compensatory mechanism stops being enough — a system that until then coped with some abnormality without symptoms loses control of it, and complaints appear.

Digital Eye Strain (DES)

Digital eye strain (also known as Computer Vision Syndrome, CVS) is not a single ailment but a collection of symptoms resulting from prolonged, focused work with screens: feelings of dryness, burning, and "sand under the eyelids," temporary blurring of vision, increased sensitivity to light, tension headaches localized around the eyes or forehead, as well as secondary discomfort in the neck and shoulders.

Digital Family Hygiene (Screen Time)

Recommendations regarding children's screen time have significantly evolved over the past decades — from simple numerical limits to a more complex approach that primarily considers the quality of content, context of use, and impact on other areas of a child's life.

Eye Motor Skills (Eye Movements)

Each eye is moved by six extraocular muscles, precisely coordinated to allow a full range of motion: the medial and lateral rectus muscles (horizontal movement), the superior and inferior rectus muscles (vertical movement), and the superior and inferior oblique muscles (rotational movements).

Heterophoria (Latent Squint)

Heterophoria is a tendency of the eyes to drift out of parallel alignment which stays invisible in everyday life, because the brain holds the eyes in the correct position through the mechanism of fusion — the merging of two images into one.

Holistic Approach (The Human as a Whole)

The holistic approach in the context of health assumes that different systems and functions of the body do not operate in isolation but influence each other — this model has been formalized in academic medicine since the 1970s as the so-called biopsychosocial model, complementing the earlier, narrower purely biomedical approach with psychological and environmental factors.

Hyperopia (Farsightedness)

Hyperopia is a refractive error in which light rays focus behind the retina instead of directly on it — most often because the eyeball is too short relative to the refractive power of the cornea and lens.

Looking into the Distance (Daylight and Vision)

Looking into the distance is not just a moment of rest for tired eyes — it is the natural "default" state of the visual system.

Myopia in Children

Myopia (myopia) is a refractive error where distant objects are focused in front of the retina instead of directly on it, causing faraway items to appear blurry while close objects remain clear.

Neurography (Fluid Lines, Calm Eye)

Neurography was developed by Russian psychologist Pavel Piskariev around 2014, combining elements of intuitive drawing with principles of cognitive psychology.

Orthoptic Exercises (Working with a Specialist)

Orthoptics is a field focused on assessing and improving the cooperation of both eyes — an orthoptist examines, among other things, convergence, eye movement, the presence and angle of any strabismus, and how the brain processes images from both eyes together.

Patching (Occlusion)

Patching is a method of managing amblyopia which consists in temporarily covering the better-seeing eye, so that for that time the child looks with the weaker one.

Presbyopia (Vision After Forty)

Presbyopia is a natural, universal process of aging of the eye: with age, the lens inside the eyeball gradually loses elasticity, and the ciliary muscle — although still functional — has less and less ability to change its shape.

Refractive Error (Parent Term)

A refractive error is a condition in which the optical system of the eye does not focus light rays precisely on the retina — the image forms in front of it, behind it, or at more than one point, resulting in blurred vision at a certain distance.

Saccades (Jumping Eye Movements)

Saccades are rapid, jumping movements of the eyeballs that shift the gaze from one fixation point to another — the fastest movements performed by the human body.

Screen Ergonomics and Distance

Screen workstation ergonomics encompasses several independent but interrelated parameters: distance from the screen, its height relative to the eyes, tilt angle, ambient lighting, and break rhythm.

Sensory Overload (Information Stress)

Sensory overload is a state of the nervous system being overwhelmed by an excess of stimuli arriving simultaneously through various sensory channels — visual (bright colors, fast editing, flashing elements), auditory (sounds, music, notifications), and cognitive (multitasking, constant attention switching).

Smooth Pursuit

Smooth pursuit is the ability to continuously and smoothly track a moving object with the eyes — unlike saccadic jumps, pursuit movement is continuous, without breaks or jumps, as long as the object moves within the capabilities of the visual system.

Stereopsis (Depth Perception)

Stereopsis is the highest, third degree of binocular vision in Worth's classification — the ability to precisely perceive depth and relative distance of objects based on slight differences between the images from the left and right eyes.

Strabismus

Strabismus (Latin: strabismus) is a condition in which the eyes are not aligned parallel — one eye looks straight ahead while the other deviates inward, outward, upward, or downward.

Suppression (Image Suppression)

Suppression is a mechanism in which the brain actively switches off the image coming from one eye, in order to avoid double vision or an image that cannot be merged with the other one.

Sustainable Technologies (Green SaaS)

The "green SaaS" (Software as a Service) model refers to designing digital services with the aim of minimizing their environmental footprint at every stage — from the way code is written, through the choice of server infrastructure, to the product distribution model to the customer.

Vision Screening in Children

A screening test is a short examination carried out in all children of a given age group, whose purpose is not to establish a diagnosis but to single out those in whom a full assessment is worth carrying out.

Vision Therapy

Vision therapy, also known as visual therapy, is a program of exercises conducted by a specialist aimed at improving selected visual functions.

Visual Acuity (Visus)

Visual acuity is the ability of the eye to distinguish fine details — measured by checking how small characters a person can recognize from a specified distance.

Visual Fixation (Gaze Stabilization)

Visual fixation is the ability to stop and maintain gaze on a selected point — a state between successive saccades during which the brain actually registers and processes visual information.

Visual Mindfulness

Mindfulness is the practice of consciously directing attention to what is happening here and now in a non-judgmental way — popularized in the West in a medical context in the 1970s, it is now widely studied for its impact on stress reduction and improvement of mental well-being.

Visual Perception (Analysis and Synthesis)

Visual perception is the brain's ability to interpret and make sense of visual stimuli reaching the retina — mere "seeing" is just the first step; perception is the brain's work that transforms raw signals into a recognizable image of the world.

Visual-Motor Coordination (Hand-Eye)

Visual-motor coordination is the ability to smoothly integrate visual perception with body movement — most commonly the hands: the eye provides information about the target's position, the brain translates this into a movement plan, and the hand executes it, with continuous real-time adjustments.