Dyslexia and web interaction: Seeing through dyslexics’ eyes Areej Al-Wabil, Panayiotis Zaphiris, Stephanie Wilson Centre for HCI Design, City University London

Overview Dyslexia and web interaction Exploratory study of web navigation: Strategies and personalised approaches Investigating dyslexics’ visual search of web pages through eye tracking March 11, 2008

Dyslexia and web interaction

Exploratory study of web navigation: Strategies and personalised approaches

Investigating dyslexics’ visual search of web pages through eye tracking

What is dyslexia? C ognitive difficulty with the written form of language I ndependent of intellectual, cultural, and emotional causation N eurobiological in origin, persistent condition H ighly individual condition – combination of difficulties and abilities that affect people to varying degrees of severity D ifficulties: reading, writing, spelling, auditory processing, visual processing, directional confusion, weakness in short term memory, organisation, sequencing, orientation S trengths: Intuitive problem solving, creativity, good at visualisation, making links between things and seeing connections March 11, 2008

C ognitive difficulty with the written form of language

I ndependent of intellectual, cultural, and emotional causation

N eurobiological in origin, persistent condition

H ighly individual condition – combination of difficulties and abilities that affect people to varying degrees of severity

D ifficulties: reading, writing, spelling, auditory processing, visual processing, directional confusion, weakness in short term memory, organisation, sequencing, orientation

S trengths: Intuitive problem solving, creativity, good at visualisation, making links between things and seeing connections

How does dyslexia affect technology use? March 11, 2008 Akiyoshi Kitaoka, Rotating Snakes (2003). This picture by Kitaoka appears to move due to the luminance contrast between the black, blue, white, and yellow.

Visual processing difficulties March 11, 2008

Visual processing difficulties March 11, 2008

Technology assistance Dyslexia is a highly individual condition Previous work has focused on interface design issues concerned with readability. Navigating the web is affected by a range of issues beyond the readability of text working memory order perception skills visual-spatial abilities March 11, 2008 SeeWord SpeakOut

Dyslexia is a highly individual condition

Previous work has focused on interface design issues concerned with readability.

Navigating the web is affected by a range of issues beyond the readability of text

working memory

order perception skills

visual-spatial abilities

Exploratory Study: Web navigation Sense Making Methodology: User-centred approach to studying and understanding users and designing systems to serve their needs March 11, 2008

Sense Making Methodology: User-centred approach to studying and understanding users and designing systems to serve their needs

Example 1 – Navigating within a web site Consistent location of main navigation Inconsistent navigation causes disorientation Scrolling difficulties – visible navigation Dynamic navigation Sensitivity to cursor movements Eye hand coordination / Dyspraxia Overlapping text Reading difficulties Reduces onscreen complexity Visual Processing March 11, 2008

Consistent location of main navigation

Inconsistent navigation causes disorientation

Scrolling difficulties – visible navigation

Dynamic navigation

Sensitivity to cursor movements

Eye hand coordination / Dyspraxia

Overlapping text

Reading difficulties

Reduces onscreen complexity

Visual Processing

Most participants were not aware of their existence – even on sites they visit often Were not perceived as useful aids exacerbate their difficulties too much information ‘ I find those - pointing to sitemaps - difficult to look at… The text gets blurred and starts moving around. Sometimes I feel a bit of anxiety coming and I need to take a break.’ Example 2 – Sitemaps March 11, 2008

Most participants were not aware of their existence – even on sites they visit often

Were not perceived as useful aids

exacerbate their difficulties

too much information

Exploratory study: Key findings Dyslexics face many of the same problems that users experience on the web, but with greater severity and in some cases to a degree in which these problems inhibit access to web content (e.g. animations and sitemaps) Dyslexic difficulties and strengths directly influence their search strategies on the web  consistency in the design  provide alternative aids Despite the existence of many standards-conforming web sites, the web still suffers from many deficiencies in support for navigation, particularly for users with dyslexia March 11, 2008

Dyslexics face many of the same problems that users experience on the web, but with greater severity and in some cases to a degree in which these problems inhibit access to web content (e.g. animations and sitemaps)

Dyslexic difficulties and strengths directly influence their search strategies on the web

 consistency in the design

 provide alternative aids

Despite the existence of many standards-conforming web sites, the web still suffers from many deficiencies in support for navigation, particularly for users with dyslexia

Investigating the visual search of web pages The exploratory study yielded results suggestive of the presence of patterns in scanning web pages by dyslexic users that may be different from typical web users. March 11, 2008  Investigate the visual scanning of web pages by examining dyslexics’ visual attention and web exploration patterns through eye tracking. Image source: Tobii.com

The exploratory study yielded results suggestive of the presence of patterns in scanning web pages by dyslexic users that may be different from typical web users.

How can eye tracking help my work? User population Difficulties in articulating their thoughts Faulty eye movements Causes of the problem are still debated by researchers Attentional processes Eye-mind hypothesis Reliable measure of attentional mechanisms March 11, 2008 Do Don’t do Diagonal of indecision Benefit of doing Cost of doing Low High High  Decision-plane model of the costs and benefits of using eye tracking in my study Adapted from (Rosenthal & Rosnow, 1984)

User population

Difficulties in articulating their thoughts

Faulty eye movements

Causes of the problem are still debated by researchers

Attentional processes

Eye-mind hypothesis

Reliable measure of attentional mechanisms

Eye tracking: Seeing through dyslexics’ eyes Eye movement researchers have used eye tracking devices to examine the visual scan path of dyslexics It has been established that visual scan paths of dyslexics differ in reading and non-reading tasks Dyslexic readers make longer fixations, more fixations, shorter saccades and more regressions than non-dyslexic readers. March 11, 2008

Eye movement researchers have used eye tracking devices to examine the visual scan path of dyslexics

It has been established that visual scan paths of dyslexics differ in reading and non-reading tasks

Dyslexic readers make longer fixations, more fixations, shorter saccades and more regressions than non-dyslexic readers.

Seeing through dyslexics’ eyes: Investigating dyslexics’ visual scan paths on the web In depth observation study: compare eye movement behaviour of dyslexic and non-dyslexic users in their interaction with the web The problem of how cognitive deficits associated with dyslexia affect web navigation is addressed in this investigation March 11, 2008 Video: Gaze replay

In depth observation study: compare eye movement behaviour of dyslexic and non-dyslexic users in their interaction with the web

The problem of how cognitive deficits associated with dyslexia affect web navigation is addressed in this investigation

Study design Data collection Performance Measures Efficiency – time on task Effectiveness – number of errors Process measures Fixations Attention switching Scan path similarity User selection Representative sample Experimental and control groups Task and Stimuli selection Navigation – ‘find a page..’  menus Informational – ‘find the contact number for..’  read/scan Exploration – free viewing  memory March 11, 2008 Accessible Inaccessible Site Nav Info Task Experimental design

Data collection

Performance Measures

Efficiency – time on task

Effectiveness – number of errors

Process measures

Fixations

Attention switching

Scan path similarity

User selection

Representative sample

Experimental and control groups

Task and Stimuli selection

Navigation – ‘find a page..’  menus

Informational – ‘find the contact number for..’  read/scan

Exploration – free viewing  memory

Dealing with data: preparation & recording March 11, 2008 Cognitive Profile

Preparing data for analysis March 11, 2008 Creating segments and defining scenes Creating filters and generating plots & maps

Design: Seeing through dyslexics’ eyes Think-Aloud Concurrent Retrospective - with or without gaze replay Care with movement run through a task Audio/Video capture Annotating gaze replay March 11, 2008

Think-Aloud

Concurrent

Retrospective - with or without gaze replay

Care with movement

run through a task

Audio/Video capture

Annotating gaze replay

Design: Seeing through dyslexics’ eyes Do dyslexics exhibit distinctive web navigation behaviour? March 11, 2008 Dyslexics Control Group

Do dyslexics exhibit distinctive web navigation behaviour?

Design: Seeing through dyslexics’ eyes Example: Strategic search patterns March 11, 2008 Dyslexics Control Group

Example: Strategic search patterns

Analysis: Dyslexics’ visual search What are the dyslexic impairments that can cause functional difficulties specifically in relation to interacting with web navigation structures? March 11, 2008 Gaze Plot Heat Map

What are the dyslexic impairments that can cause functional difficulties specifically in relation to interacting with web navigation structures?

Explore how dyslexic difficulties (e.g. weak short term memory) relate to behaviour and performance measures? Analysis: Dyslexics’ visual search March 11, 2008 Direction of scanpaths, # of fixations Dwell time, spatial density of fixations Apply filter WeakMemory  Examine data

Explore how dyslexic difficulties (e.g. weak short term memory) relate to behaviour and performance measures?

Analysis: Dyslexics’ visual search March 11, 2008 Export to statistical software packages Statistical analysis provided by Studio

Final notes Performance data does not always tell the whole story. Eye movements provide a more complete picture of interaction by filling in the gaps between observable events. Participant set-up is important Apply selectively to the right problems Temptation to over interpret Relating eye tracking metrics to cognition March 11, 2008

Performance data does not always tell the whole story. Eye movements provide a more complete picture of interaction by filling in the gaps between observable events.

Participant set-up is important

Apply selectively to the right problems

Temptation to over interpret

Relating eye tracking metrics to cognition

Thank you Areej Al-Wabil, Panayiotis Zaphiris, Stephanie Wilson Centre for HCI Design, City University London, UK [email_address] [email_address] [email_address] March 11, 2008