Visual Perception
The ability to interpret and use what is seen
Interpretation
A mental process involving cognition and gives meaning to visual stimulus
Perception
Cognitive process that changes as a function of learning, labeling and experience (learning from what is seen and experienced)
Hierarchy of Visual Perceptual Skill Development
(bottom) Oculomotor, Visual Fields, and Visual Acuity---> Attention=Alerting and Attending---> Scanning---> Pattern Recognition---> Visual Memory---> Visuocognition---> Adaption
Oculomotor Control
Efficient eye movement
Visual Fields
Ensures the visual info sent to CNS is accurate, Awareness of physical space
Visual Attention
Being alert and attend to what you see
Scanning
The retina records the detail of the scene systematically
Visual Memory
Ability to retain information for recall (Remembering from what you've seen), short or long term, sequential
-Domain specific: how to, procedural things, facts, events, images
Visual Cognition
Integrates visual info with other senses to problem solve, formulate plans and make decisions (visual attention, memory, discrimination, and imagery)
Adapt
Able to make changes to accommodate visual input
Information Processing
Focuses on how the learner attends to, recognizes, transforms, stores, and retrieves info for later use
-Requires input, processing, and output
-Input: Environmental stimuli (objects, space, events, representations, and symbols)
-Processing: Visual percep
Visual Reception
Receive visual input
Fixation
Focus on stationary object
Pursuit
Focus on moving object
Saccadic Eye Movement
Gaze shift, fixate from one object to another rapidly
Accuity
Fine details of object
Accommodation
Focus on varying distances
Binocular Vision
Combines images from 2 eyes into 1
Stereopsis
Depth perception
Convergence/Divergence
Bring eyes in then out
Selective Attention
Being able to screen out irrelevant info
Vigilance
Concentrates on visual stimuli
Divided Attention
Focus on 2 stimuli at once
Visual Discrimination
Identifying differences in details, requires recognition (key feature relating to memory), matching, and sorting
Object Perception
Form constancy, figure ground, and visual closure
Form Constancy
Recognition of objects
Visual Closure
Recognition with a partial picture
Figure Ground
Seeing objects within busy backgrounds
Spatial Relations
Up, down, oneself
Depth Perception
Seeing distances, how far away something is
Topographical Orientation
How to get to objects (routes, maps)
Matching
Similarities in stimuli
Sorting/Categorization
Note differences (size, shape)
Visual Imagery/Visualization
Seeing things in your mind
Visual Motor Integration
Motor combined with vision
Effected Occupations from Poor Visual Perceptual Development
ADL's, play, reading, writing, spelling, math
Function/Dysfunction Continua in Relation to Visual Perception
Independence<---------->Dependence
-Based on visual reception, visual cognition, and visual discrimination skills
Problems with Visual Reception Skills
No scanning, use finger to follow lines in reading, often lose place when reading, complain of blurry words, squinting
Problems with Visual Cognition (Attention and Memory)
Distracted easily, focus on irrelevant info, fatigue easily, poor attention to detail, poor handwriting
Problems with Visual Discrimination Skills
Difficulty recognizing words/numbers, see letters/numbers in reverse, difficulty finding sleeves in all white or black shirts, could become lost easily, over or under spacing in writing
Neurophysiological Approach to Intervention
Aim to address maturation of the human nervous system and link it to human behavior
Skill Development Approach to Intervention
Attempt made to improve child's ability to profit from standard instruction (practice, repetition)
Compensatory Approach to Intervention
Classroom materials or instructional methods are modified to accommodate the child's limitations
Optometry Approach to Intervention
OT works closely with OD to accommodate environmental modifications
Postulates Regarding Change
3 Main
-Teaching/learning principles utilized to affect change (feedback)
-Environment fosters growth through developmentally appropriate challenges
-Environment encourages development of component parts of skills or specific skills
6 Specific
-Improved v