For the next two weeks, we will dive deeply into image description. Here I'll provide some information on how children who are blind learn about the visual world and things you should consider when providing image description. While you may never be in a situation to create alt text focused for images intended for children, this background information may enhance your understanding of web accessibility in general.

Next week, we will review the most effective ways to describe complex images such as charts, diagrams and illustrations.

In Weeks 4-6, we'll return to broader issues including specific ways to improve web accessibility (and universal design), how to add captions and descriptions to videos, and how web and publishing standards are likely to change in the future.

Week 2: Describing Images for Children and Adults

I. Review of Alt Text or Image Description Practices.

Types of Images

Images that are Eye Candy = Do Not Describe
Images that are really Links and Buttons = Provide function not image description
Images that Convey Information = Require Description

What I Need to Write Image Descriptions:

Detailed knowledge of the subject matter
Good writing skills and an excellent command of the vocabulary associated with the subject
Adequate access to reference and support materials to ensure that the descriptions are as clear and accurate as possible
Descriptions should be reviewed for accuracy by someone other than the original writer

What Do I Write?

Always Consider Context:
Why is the image there?
Who is the intended audience?
If there is no description what will the reader miss?
What information is included in the surrounding text?
Is there an image caption?

II. Describing for Children

Description for children is fundamentally different than description for adults. With adults, one can assume a certain level of exposure, whether it originates with having sight earlier in life or from exposure to language and concepts in literature, TV, films, or in other cultural experiences. The same cannot be said for children with vision loss, whose experiences are limited by the visual impairment and time itself.

Children with blindness and visual impairment obtain information in 3 fundamentally different ways than sighted children.

Inconsistent - things do not always make noise or produce an odor
Fragmented - comes in bits and pieces
Passive - not under the child’s control

As a result, children with visual impairment generally share the following three learning principles:

1. Parts to Wholes

A blind child can only touch an area as large as his or her hand at any one point in time, and then must put together those multiple tactile experiences to get a sense of the whole object.
“It’s a bit like putting together a puzzle without knowing what the end product looks like.”
Example: A blind child's knowledge of the family car might be limited to the car seat that they sit in. The driver's steering wheel, pedals, the size of the car and its relation of other vehicles on the road may not be realized for many years. Whereas a child with sight might imitate their parent's driving habits with a toy steering wheel before they can even speak.

2. Deliberate vs. Incidental

Children with visual impairment usually will not benefit from incidental learning.
Example: In the game of baseball, the batter stands at home plate. Anecdotally, I've heard life-long baseball fans who are blind say that they assume that home plate is shaped like a round dinner plate. Whereas children who are sighted know what home plate looks like within moments of watching their first baseball game or even seeing photos of a baseball field. While knowing the shape of homeplate is not critical to understanding or enjoying the game of baseball, I've always found this to be a profound example of what is missed when one does not have access to incidental learning.
Here's a photo of home plate.

3. Limited Opportunities for Imitation and Practice

Children often learn skills by watching others perform them, trying it themselves, and practicing the behavior repeatedly until they obtain the desired result.
Children with visual impairment do this, too, but they rely on other types of sensory feedback that do not provide the same type of information.
Example: When children learn how to swim, they both listen to the swimming instructor and gaze across the pool to watch how other children are swimming. Without knowing it, they watch the breathing, strokes and kicks of others and imitate them. Children with visual impairments do not benefit from this type of imitation.

When describing for younger children:

Young children generally have short attention spans and may find it difficult to listen to and absorb large amounts of verbal information (RNIB, 2006).
Think about description from the point of view of the child with vision loss. What seems obvious to a sighted child may be totally obscured to a child with vision loss.

Use:

Short sentences
Vocabulary that is age appropriate
Keep it focused on action and emotion
Few details
Emphasize the tactile

Example: Describe a tennis ball as "the size of an apple and fuzzy" as opposed to "bright yellow with the word 'Penn' printed in green."

III. Describing for Older Children and Adults

People with the exact same visual diagnosis, age, and vision loss may have entirely different experiences in terms of concept development: one cannot be sure that every child or adult has had the same experience. Description writers have no control over who is listening to the description and thus they need to prepare for multiple levels of understanding.

When describing for older children and adults:

Assume more experience with visual elements, however, make no assumptions as audience is still varied.
Use longer sentences
Focus on tactile, color, placement of objects
Add social concerns (for example: body language and facial expressions, fashion)
Keep it focused
Vocabulary that is age appropriate

IV. Assignment

* Read: WebAIM's Creating Accessible Images

* Do:

Option 1: Write 2 different alt texts for each of the 6 attached images. Write one alt text for a 6 year old and one for an adult. Keep in mind that these images are out of context so that in this exercise there is no "correct" alt text. Rather, these are intended to be a bit of fun and to spur discussion
Option 2: Provide alt text for images within your own websites.

* Discuss: Your image descriptions and your approaches and challenges. Please use the Forum space for this, ie., Forum topic: "Discussion of Week 2 Image Descriptions"

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