205 #3 hand/vision/oral motor development

Eye Dominance

“stronger” or lead eye, typically same as dominant hand,
but not always

Eye Position

position of eyes at rest; should be in neutral and equal; lack of a neutral position (inward or outward deviation) could mean a muscle imbalance

Central Vision

vision in front; processes “what is it”

Peripheral Vision

side vision; processes “where is it,” deals with motion

Accommodation

ability of eyes to adjust focus

Binocular Vision

the ability to use both eyes together

Convergence

ability of eyes to smoothly follow a moving target from distance (far) to midline (near) – crossing eyes

Divergence

ability to eyes to smoothly follow a moving target from near to far

Fixation

ability to direct a gaze and hold an object steadily in view. It is a foundation skill for all oculomotor behaviors.

Eye Tracking

the ability of the eyes to smoothly and effortlessly follow a moving target.

Saccades

rapid, ballistic movements of the eyes that abruptly change the point of fixation; shifts from one target to another, voluntary.

Smooth Pursuits

much slower tracking; the eye’s ability to smoothly follow a moving target; designed to keep a moving stimulus on the fovea. Such movements are under voluntary control

Vestibulo-ocular movements/reflex

moves the eyes at same speed but opposite direction of the head in order to stabilize the eyes relative to the external world, prevents visual images from “slipping” on the surface of the retina as head position varies. Automatic, involuntary

Convergence Insufficiency

eye teaming problem

Amblyopia

lazy eye”

Diplopia

a single object is perceived as two rather than one; double vision.

Nystagmus

rhythmic oscillations or tremors of the eyes which occur independent of the normal eye movements. not curable,
but it is manageable. Treatments include prescription glasses or contact lenses, prisms, and vision therapy.

Strabismus

misalignment of eye(s); turned eye (s), eyes send conflicting images to the brain, and the brain cannot
combine these images as it would in normal vision. The brain compensates by ignoring one image in favor of the other, causing a loss of depth perception. Strabismus in more common in children and affects 4% of all children (although it may also appear later in life).

Esotropia (ET)

a condition in which an eye is turned either
constantly or intermittently inward toward the nose. Esotropia is a type of strabismus.

Exotropia (XT)–

a condition in which an eye is either constantly or
intermittently turned outward toward the ear. Exotropia is a type of strabismus. It may also be called divergent strabismus, wandering eye, or wall eye(s).

Visual Perception

umbrella term; combination of vision and cognition; using eyes to receive visual information and brain interprets it

Visual Motor Integration/ Eye Hand Coordination

combining visual information with movements of your body

Visual Perceptual Disorders

information processing dysfunctions of the visual system; can be a directionality/laterality disorder, visual form dysfunction, visual memory dysfunction, and visual-motor dysfunction. Vision therapy is a treatment option.

Object Perception incldues?

form constancy, visual closure, figure ground

Spatial Perception includes

position in space, depth perception, topographical orientation, object focused spatial abilities

Visual Cognitive Abilities

visual discrimination, visual memory, visual attention

Form constancy

Ability to recognize forms and objects as the same,
regardless of size, color or orientation, ex. child can
recognize a triangle regardless of which way it is turned,
how big it is or what color it is

Visual closure

Ability to mentally visualize what something looks like,
even if it is only partially visible, ex. child can visualize
what the whole pencil looks like even if it is half covered
by the pencil case

Visual figure ground

Ability to distinguish an object/figure from its
background, ex. finding a particular toy in the toy box,
finding your spot on the page or on the blackboard

Position in space

Ability to recognize the spatial relationship between
yourself and objects in the environment, as well as
relationship between objects, important for directional
language such as up and down; in front of and behind;
between, left and right

Depth perception

Ability to judge how far away something is from
yourself or another object, ex. judging the depth of
stairs when walking up or down

Topographical Orientation

ability to understand route to destinations through
understanding of position of objects

Visual attention

Ability to orient and maintain focus on
external stimuli

Visual discrimination

Ability to look at objects or pictures and
recognize whether they are alike or different.
This is important for matching and categorizing

Visual memory

Ability to remember, even for a short period,
something you have seen