As part of your AAOT Foundation Learning, you have been asked to complete the recommended Vision Australia learning for Occupational Therapists and support workers.

We have included this learning because vision can have a substantial effect on occupational performance, mobility, safety, communication and community participation. Yet vision-related difficulties can sometimes be overlooked, misunderstood or attributed to another disability.

This is particularly important in assistance-animal practice. A person may be referred for an assistance animal because they are having difficulty with:

• navigating environments;
• recognising obstacles;
• travelling independently;
• locating objects;
• judging steps or changes in surface;
• reading signs or information;
• coping in unfamiliar environments; or
• safely participating in the community.

The fact that somebody already has another diagnosis does not mean that diagnosis necessarily explains every difficulty they experience.

For an AAOT, the important question is:

What is actually causing or contributing to this person’s occupational difficulty?

Sometimes the answer may involve vision.

Vision Is More Than Visual Acuity

When people think about vision impairment, they often think primarily about whether someone can read an eye chart.

Functional vision is considerably more complex.

Different conditions can affect:

• visual acuity;
• visual fields;
• contrast sensitivity;
• depth perception;
• peripheral vision;
• central vision;
• colour perception;
• light sensitivity;
• visual processing;
• adaptation between different lighting conditions; and
• the ability to use available vision efficiently in everyday environments.

A person may therefore experience significant vision-related functional difficulties without simply describing their experience as:

“I can’t see.”

An AAOT should avoid reducing vision assessment to whether somebody wears glasses or can read standard print.

Understanding Light and the Electromagnetic Spectrum

Before considering colour vision, it is useful to understand what human beings actually mean by visible light.

Light forms part of the much broader electromagnetic spectrum.

In simplified order, the electromagnetic spectrum includes:

radio waves → microwaves → infrared → visible light → ultraviolet → X-rays → gamma rays

What humans call visible light represents only a very small portion of this spectrum, approximately 380–700 nanometres, although the precise boundaries vary somewhat between individuals and sources.

Radiation outside the human visible range still exists even though we cannot see it. \

Different species have evolved different sensory systems. Therefore:

The fact that a human cannot perceive a particular part of the environment does not mean that another species experiences that environment in the same way.

This becomes particularly important when the intervention itself involves an animal.

How Humans Perceive Colour

Human colour perception results from the interaction between light, objects, the eye and the brain.

Humans typically have three types of cone photoreceptors contributing to colour vision and are therefore described as having trichromatic vision.

Different wavelengths of visible light stimulate these receptors in different combinations, allowing most humans to distinguish a very large range of colours.

However, not everybody has the same colour perception.

A person with a colour-vision difference may have difficulty distinguishing particular colours or combinations of colours while having otherwise useful vision.

This is another reason that:

vision impairment ≠ simply seeing less

and

colour-vision difference ≠ blindness.

Dogs Do Not See the World the Way Humans Do

This is particularly relevant to assistance-animal practice.

Dogs do not have human-like colour vision.

Where humans are typically trichromatic, dogs have dichromatic vision. Their colour perception is principally associated with blue and yellow ranges, together with variations in brightness.

It is therefore common to simplify canine colour vision by saying:

Dogs primarily see blue, yellow, black, white and shades between them.

More precisely, colours that humans perceive as red, orange or green are not differentiated by dogs in the same way and may appear as yellowish, brownish, greyish or otherwise less distinct shades.

Dogs are not simply seeing a black-and-white world, but neither are they seeing the full range of colours experienced by a person with typical human colour vision.

This has practical implications for:

• training equipment;
• toys;
• target objects;
• environmental markings;
• assistance-animal equipment;
• visual cues; and
• assumptions about what an animal can visually discriminate.

Two objects that look dramatically different to a human because of their colours may be much less visually distinct to a dog.

This illustrates an important AAOT principle:

Never assume that another species perceives an environment in the same way that you do.

Colour Vision Is a Useful Assistance-Animal Example

Colour-vision difference provides a useful example of why diagnosis alone should not determine an assistance-animal recommendation.

Imagine a young adult with a colour-vision difference has difficulty identifying colour-coded files, equipment, clothing or information within everyday activities.

Someone suggests:

“Perhaps an assistance dog could identify the colours for them.”

Before considering an animal, the OT should identify the actual occupational barrier.

Could the problem instead be addressed through:

• written labels;
• symbols;
• patterns;
• high-contrast markings;
• accessible digital information;
• colour-identification technology;
• smartphone accessibility tools; or
• redesigning the environment so important information is not communicated by colour alone?

These interventions may provide a much simpler and more reliable solution.

There is also an obvious problem with assuming a dog can simply compensate for human colour-vision differences:

Dogs themselves do not have typical human colour vision.

A dog might potentially learn to distinguish particular objects using brightness, shape, position, scent, texture or other cues, but that is different from assuming that the dog understands or perceives human colour categories in the way we do.

The correct professional question is therefore:

What information does this person actually need, and what is the safest, simplest and most effective way of making that information accessible?

Not:

“They have a colour-vision difference, therefore they need an assistance animal.”

This reinforces a principle that applies throughout AAOT:

Do not begin with “What can we train an animal to do?” Begin with “What is the occupational barrier, and what is the most appropriate way of addressing it?”

Vision Difficulties Can Be Missed

Some people live with unrecognised or insufficiently assessed vision difficulties for considerable periods.

This may be particularly important where someone already has another disability.

For example, a child with autism may:

• avoid particular environments;
• appear hesitant on stairs;
• become distressed in visually complex spaces;
• struggle with particular classroom activities;
• move unusually through unfamiliar environments; or
• appear reluctant to participate in some activities.

It may be tempting to attribute all of these behaviours to autism.

But what if the child also has an unidentified vision impairment?

The broader principle is:

An existing diagnosis should not become the automatic explanation for every new functional difficulty.

Diagnostic Overshadowing

Diagnostic overshadowing can occur when symptoms, behaviours or functional difficulties are attributed to an existing diagnosis without adequately considering alternative explanations.

For example:

“They avoid unfamiliar places because they are autistic.”

may overlook:

“They cannot reliably see obstacles in part of their visual field.”

Likewise:

“They are anxious when walking outside.”

may overlook a visual difficulty affecting safe navigation.

The same problem can occur for people with:

• intellectual disability;
• acquired brain injury;
• psychosocial disability;
• neurological conditions;
• developmental disability;
• ageing-related conditions; or
• multiple disabilities.

An AAOT should remain professionally curious.

Observe Function, Not Just Diagnosis

Occupational Therapy is particularly well placed to identify discrepancies between a diagnosis and a person’s actual functional performance.

Consider what happens when the person:

• moves through unfamiliar environments;
• transitions between light and dark spaces;
• uses stairs;
• locates objects;
• reads information;
• identifies hazards;
• navigates crowds;
• reaches for objects;
• performs self-care;
• uses technology; or
• interacts with an animal.

You are not expected to diagnose an ophthalmological condition.

You are expected to recognise when:

“Something about this person’s visual function may require further assessment.”

and refer appropriately.

Know the Limits of Your Scope

An AAOT is not expected to become an:

• ophthalmologist;
• optometrist;
• orthoptist;
• orientation and mobility specialist; or
• specialist vision-rehabilitation practitioner

unless separately qualified in that area.

When vision concerns arise, appropriate interdisciplinary assessment may be necessary.

The goal is not to diagnose beyond your competence. It is to recognise when vision may be contributing to occupational performance and not overlook it simply because the referral is about an assistance animal.

Assistance Animals Are Not the Automatic Response to Vision Impairment

Discovering a vision impairment does not automatically mean:

“This person needs a Dog Guide.”

As throughout AAOT, assessment should begin with the person’s:

• functional needs;
• goals;
• existing strategies;
• environment;
• preferences;
• capabilities;
• risks; and
• available alternatives.

Depending upon the person’s needs, appropriate interventions might include:

• environmental modification;
• lighting changes;
• contrast modification;
• magnification;
• accessible technology;
• orientation and mobility training;
• mobility aids;
• human assistance;
• occupational strategies;
• specialist vision rehabilitation; or
• combinations of approaches.

A Dog Guide may be appropriate for some people.

It is not the universal intervention for vision impairment.

Dog Guide and Vision Dog Terminology

Within AAOT, we use Dog Guide or Vision Dog as broad descriptive terminology where appropriate.

You may also encounter terms such as Guide Dog and Seeing Eye dog in everyday language, organisational names and international contexts. Some terminology may be associated with particular organisations or protected branding.

Where an individual or organisation uses particular terminology, respect that terminology where appropriate.

Blindness Does Not Automatically Mean Someone Wants a Dog Guide

A blind or low-vision person may never have considered a Dog Guide.

Others may have considered one and decided against it.

Some people may prefer:

• a long cane;
• electronic navigation;
• human guiding;
• environmental strategies;
• orientation and mobility techniques; or
• combinations of supports.

Some people simply do not want to live or work with a dog.

Do not assume:

blind person = Dog Guide

The person’s preferences remain central.

A Dog Guide Is Not a Replacement for Orientation and Mobility Skills

A Dog Guide and handler work as a team.

The dog is not expected to independently decide where somebody wishes to go and simply transport them there.

The handler remains actively involved in navigation and decision-making.

This distinction is important because participants, families and other professionals can have unrealistic expectations about what Dog Guides actually do.

Specialist orientation and mobility input may therefore be important when this form of assistance animal is being considered.

What Is the Animal Actually Being Asked to Do?

Vision-related referrals provide an excellent example of why AAOTs must identify the actual task rather than relying upon broad statements such as:

“The dog helps with their vision.”

Ask:

• What does the person actually have difficulty doing?
• What does the animal actually do?
• What sensory information is the animal using?
• Is that behaviour trainable?
• Is it reliable?
• What functional outcome does it produce?
• Is specialist Dog Guide expertise required?
• Is another intervention more appropriate?

Understanding differences between human and canine sensory perception becomes particularly relevant here.

We should not attribute human reasoning or sensory abilities to an animal simply because the trained behaviour produces a useful outcome.

Children and Vision-Related Assistance-Animal Referrals

Vision difficulties in children may present differently from those in adults.

Importantly, a child may not know that their visual experience differs from everybody else’s. They may have no reference point for what constitutes typical vision.

Adults may instead notice:

• unusual positioning;
• reluctance to move through particular environments;
• difficulty finding objects;
• frequent collisions;
• difficulty with stairs;
• avoidance of visual activities;
• distress in particular lighting;
• apparent clumsiness;
• difficulty recognising people or objects; or
• inconsistent performance.

Where a child has another disability, these observations should not automatically be attributed to that diagnosis.

Ask:

Could something else be contributing?

Listen to Parents and Carers—But Also Observe the Person

Parents, carers, teachers and support workers can provide extremely useful information.

However, distinguish between an observation and an interpretation.

For example:

“She refuses to go down stairs because of her autism.”

contains both.

The observation is:

She is reluctant to use stairs.

The explanation:

because of autism

requires further assessment.

Separate what is happening from assumptions about why it is happening.

Vision, Neurodivergence and Sensory Processing Can Overlap

Vision-related difficulties may coexist with:

• autism;
• ADHD;
• sensory-processing differences;
• neurological disability;
• intellectual disability;
• physical disability;
• psychosocial disability; or
• other conditions.

A person may simultaneously experience:

visual impairment + sensory differences + anxiety + environmental barriers

Each may affect occupational participation differently.

Good assessment allows complexity rather than forcing every difficulty into one diagnostic explanation.

Environmental Modification May Be Powerful

Sometimes relatively straightforward environmental changes can substantially improve participation.

Depending upon individual needs and specialist recommendations, examples may include:

• improved lighting;
• reduced glare;
• increased contrast;
• clearer pathways;
• tactile indicators;
• enlarged information;
• accessible digital formats;
• symbols or patterns rather than colour alone;
• consistent organisation;
• removal of hazards; or
• changes to environmental layout.

An assistance animal should not be recommended simply because it appears more sophisticated than a straightforward environmental intervention.

The intervention should fit the occupational need—not the other way around.

Assistance Animals Can Introduce New Risks

An animal may assist with mobility while simultaneously changing the person’s environment.

Consider:

• lead or harness management;
• positioning;
• stairs;
• crowds;
• public transport;
• other animals;
• emergency evacuation;
• environmental obstacles;
• animal behaviour;
• the person’s physical capacity; and
• interactions between mobility aids and the animal.

The AAOT should consider the whole occupational system, not simply the proposed animal task.

Vision Impairment and Animal Care

A blind or low-vision person can absolutely provide excellent animal care.

Do not assume that vision impairment means somebody cannot feed, groom, exercise, train, monitor or care for an assistance animal.

Instead, identify the strategies and supports that person uses.

Practical considerations might include:

• recognising subtle physical changes;
• accessing medication information;
• administering treatment;
• inspecting equipment;
• monitoring wounds;
• identifying environmental hazards; or
• accessing veterinary information.

Accessible strategies and supports can be developed where required.

The appropriate question is:

What does this particular person need to care for this particular animal safely and sustainably?

The Animal’s Welfare Remains Central

As with every assistance-animal intervention, benefit to the person does not override the animal’s welfare.

Consider the animal’s:

• health;
• temperament;
• training;
• workload;
• rest;
• environmental stress;
• equipment;
• veterinary care;
• behavioural welfare; and
• suitability for the required work.

Dog Guide work can be physically and cognitively demanding.

The animal is not simply a mobility device.

Existing Dog Guide Teams Require Respect for Established Expertise

An AAOT may encounter someone who already works successfully with a Dog Guide provided or supported by a specialist organisation.

General assistance-animal knowledge does not automatically make you the appropriate professional to alter established Dog Guide training or handling practices.

Where relevant, collaborate with:

• the handler;
• specialist Dog Guide professionals;
• orientation and mobility practitioners;
• vision professionals;
• veterinarians; and
• other members of the person’s team.

Recognising the expertise of other disciplines is part of competent interdisciplinary practice.

Avoid Unnecessary Assumptions About Independence

A person’s use of a:

• Dog Guide;
• cane;
• human guide;
• assistive technology;
• support worker;
• environmental modification; or
• combination of supports

does not determine whether they are “independent”.

Independence should not simply mean:

doing everything without assistance.

Autonomy, choice, control and meaningful occupational participation are more useful considerations.

What This Means for an AAOT

Your external vision-related learning should encourage you to ask:

Could vision be contributing to this person’s functional difficulty?

Am I attributing everything to an existing diagnosis?

What have I actually observed rather than assumed?

Does this require specialist vision assessment?

What is the person’s actual occupational goal?

What alternatives or environmental modifications have been considered?

Does the person actually want an assistance animal or Dog Guide?

What is the animal actually being asked to do?

What sensory information is the animal capable of perceiving?

Am I incorrectly assuming that a dog sees the environment as a human does?

Is the proposed task safe, realistic and proportionate?

Do I need specialist Dog Guide or orientation and mobility input?

What are the animal-welfare implications?

The key principle is:

Do not allow an existing diagnosis, a vision diagnosis or an assistance-animal referral to substitute for individual occupational assessment and professional reasoning. Understand the functional problem first, then determine the most appropriate intervention.

Continue This Topic in Your Reflective Workbook

You have now completed the foundation material for:

Topic 12 — Vision-Related Practice

Please complete the recommended Vision Australia learning for Occupational Therapists/support workers identified in your AAOT Foundation Learning requirements and then refer to the corresponding section of your AAOT Foundation Learning Reflective Workbook.

The workbook will ask you to apply this learning to realistic assistance-animal situations involving:

• possible undiagnosed vision impairment;
• diagnostic overshadowing;
• autism and vision;
• functional observation;
• referral to vision professionals;
• the electromagnetic spectrum and visible light;
• human and canine visual perception;
• colour-vision differences;
• environmental accessibility and colour coding;
• blind and low-vision participants;
• Dog Guide choice;
• orientation and mobility;
• environmental modification;
• accessible animal care;
• interdisciplinary practice; and
• animal welfare.

In particular, you will encounter situations where the obvious explanation may not be the correct one—including a child whose difficulties have been attributed to an existing disability and a young adult who has been told that an assistance animal could solve a colour-vision-related occupational difficulty.

The purpose is not to turn you into a vision specialist. It is to develop the professional habits of asking:

“What else might explain what I am seeing?”

and, importantly when working with assistance animals:

“Am I assuming the animal sees and interprets the world in the same way that I do?”

You may return to these activities throughout AAOT as your knowledge develops. Your reflections may also contribute to your Capstone Portfolio, Capstone projects and later integrated case work.

Once you have completed or commenced the corresponding workbook activities, continue to Topic 13 — Manual Handling and Safe Lifting.