Vision and Visual Perception Overview

Question 1

Optic Nerve

Answer 1

Blind spot

Question 2

What is the fovea of the eye?

Answer 2

• Light sensitive lining of the eye
• Sends light from lens to the fovea to send neural signals to the brain to stimulate neural recognition
• Of the eye, it has the greatest ability to process detail

Question 3

What does the macula do?

Answer 3

• It is the most highly developed (most keen)

- It is inside the fovea

Question 4

What does it mean if someone is not capable of convergence of the eyes?

Answer 4

• An ocular muscle may not be working and prevent the eyes from converging. If this happens then coordination and proprioception are impacted

Question 5

Vision

Answer 5

• Primary sensory system used to acquire information about the environment
• One of the most complex systems of sensation, furthest reaching, and fastest

Question 6

Optical System vs Cortical System

Answer 6

• The optical system gives individuals the ability to see objects
• The cortical system is used to interpret what is being seen

Theses systems are integrated in order for individuals to be able to adapt

OT analyzes the functional impact of visual disturbances. OT can provide treatment but it must be justified and ethical. If it is out of the scope of practice a referral is needed

Role in:

1) Anticipatory process
2) Language and comprehension
3) Oculomotor dysfunction

Question 7

Visual Processing

Answer 7

• Influences motor planning and postural control
• Allows us to anticipate information necessary for successful adaptation to the environment

Occurs in two modes: focal and ambient

Question 8

Visual Processing - Focal

Answer 8

• Attentive vision

- Provides attention to important features of an object for perception and discrimination

Question 9

Visual Processing - Ambient

Answer 9

• Peripheral or pre-attentive vision
• Works in connection with proprioceptive, kinesthetic, tactile, and vestibular systems
• Organizes and stabilizes visual field
• Detects events in environment and their location in space/distance from individual

Question 10

Information Processing

Answer 10

• Optical input: eye health/integrity of optical system
• Integration: sensory information is blended and results in plan which guides response
• Output: ocular-motor response

Question 11

Adaptation Through Vision

Answer 11

• Hierarchy as opposed to independent skills
• Visuocognition is the ability to integrate sensation and make plans
• If there are problems at the bottom of the pyramid then there will be problems above

Question 12

What is pattern recognition?

Answer 12

• Identifying the salient features of an object and using these features to distinguish the object from its surroundings
• The ability to identify the holistic aspects of an object; to see its general shape, contour, and features
• The ability to identify specific features of an object such as details of color, shading, and texture
• Both aspects of recognition must occur for accurate identification
• Pattern recognition can’t be accomplished without organized and thorough scanning of the visual scene

Question 13

What is visual memory?

Answer 13

• The ability to create and maintain a picture of an object in the minds eye, keeping and storing an image and calling it up at a later date
• Before an image can be stored in memory, there must be recognition of the pattern making up the image. Must be able to store and recall from ST and LT memory