Cognitive aging and rich internet applications: Usability problems of Ajax based on the empirical study of older adults


Yuuki Hara, Design Division, Hitachi, Ltd., Akasaka Biz Tower, Akasaka 5-3-1, Minato-ku, Tokyo 107-6323, Japan. (E-mail:


Ajax is a new technology that supports asynchronous input-output of data and has better operability and more representational power than simple HTML. For all users to take advantage of it, Ajax needs to be presented in a way that is easy to use. In this study, three experiments were conducted using usability testing methods. We identified several usability problems of Ajax websites for older adults (Experiment 1) and created some possible design solutions for three of the problems related to the essential features of rich internet applications like Ajax. We then tested these solutions (Experiments 2 and 3) to demonstrate the effectiveness of the three design strategies applied to them.

The internet has played an important role in improving our quality of life over the last 15 years. To meet users' needs, the functions of and information on the internet have increased dramatically. Rich internet applications (RIAs) have been developed as part of these changes. A RIA is a web application that has better operability and more representational power than those made using simple HTML. A HTML-based web application is like a stack of static cards, where clicking a link on a page leads to refreshing the whole page and then displaying the next page. When searching for some information, users have to wait for the whole page to be refreshed every time they change the search criteria to obtain better results. In contrast, RIAs support the asynchronous input-output of data, which enables the screen to partially refresh without page transition. This feature gives users real-time system responses to operations and reduces waiting time significantly.

RIAs have without doubt enhanced the usability of information browsing and web services for younger adults who are familiar with information technology in general. However, can older adults really become accustomed to the new rules of the user interface brought about by new web technology? For example, users who are not expecting it sometimes do not notice when pages were partially reloaded, which is one of the essential features of RIA. To enjoy the benefits of RIA, users have to notice that a part of the page has been changed, when they may have expected to open a new page, and to recognize the differences between old and new information. Performing these cognitive activities requires selective attention and episodic memory, which have been found to deteriorate with age in cognitive aging studies (Craik, 2000; Rogers, 2000).

According to a survey conducted by the Ministry of Internal Affairs and Communications (2009), 75.3% of Japanese people who are 5 years old or greater use the internet. However, the internet use rate for older adults is less than half: 37.6% for those between 65 and 69 years old, 27.7% for those between 70 and 79 years old, and 14.5% for those over 80 years old. Some people are concerned that the information gap between younger and older adults is becoming a serious problem. Web designers need to know that RIAs can cause new usability problems for older adults and learn how they can help older adults use web applications such as RIAs comfortably with new technologies.

In this study, we specified the usability problems of RIA websites for older adults (Experiment 1), created some possible design solutions for three of the problems related to the essential features of RIA, and then tested these solutions (Experiments 2 and 3) by usability testing, which is a method for finding critical issues of human-artifact interaction in a realistic setting (Dumas & Redish, 1999; Harada, 1993).

Experiment 1

The purpose of Experiment 1 was to investigate the usability problems of RIA for older adults by conducting usability tests of Ajax (Asynchronous JavaScript + XML) websites. Ajax is one of the RIA technologies. A primary characteristic of Ajax is that it increases the responsiveness and interactivity of web pages by exchanging small amounts of data with the server “behind the page,” so that entire webpages do not have to be reloaded each time data is fetched from the server. Ajax has been adapted to various websites.


Participants.  Eighteen older adults ranging in age from 60 to 70 years old (nine women and nine men, average age 66.6 years) were recruited from the local senior personnel centre. All were novice PC users with fundamental website operational skills, such as being able to use a mouse and keyboard and being able to browse websites by themselves.

According to the World Health Organization, older adults are defined as those who are over 65 years old; however, we have often observed that people in their early 60s face similar problems to those over 65 years old in testing the usability of various websites. Therefore, we have decided to recruit people over 60 years old as the participants in this study.

Participants were assigned to each of the two task sets (A or B); the first ten participants were assigned to task set A and the other eight participants were assigned to task set B.

Apparatus.  A desktop PC with a 17-in. LCD (1280 × 1024 pixels), a keyboard, and a wheel mouse were set up. Digital video cameras were set for recording participants' behaviors and comments.

Procedure.  Usability testing with the think-aloud method was conducted one participant at a time. First, the task description sheet was given, and a participant was asked to read aloud. Before starting the task, the participant was instructed to state their thoughts during the operation, for example “I don't know where this link goes, but I don't seem to have any other choice,” and to try to complete tasks by his or herself. If participants could not continue the task and expressed their desire to “give up” to the experimenter, the task was regarded as incomplete.

After the completion of the task, a brief interview was conducted. Participants' behavior and comments were digitally recorded throughout the session.

Materials.  The main feature of Ajax websites is that sections of pages can be reloaded individually without page transition. In this experiment, six Ajax websites including the features described above were presented to the participants. These websites were grouped into two types in accordance with their information search methods: search query and search parameters. The Ajax websites with a search query display suggested that search keywords of text be entered into the search query field; this helps users to enter relevant search keywords. The Ajax websites with search parameters display results in a section of the same page without page transition, immediately after each search parameter is chosen; this enables users to search for information more interactively and quickly.

Tasks.  Six tasks in Table 1 were designed to investigate the use of search query (Tasks 1 and 2) and search parameters (Tasks 3, 4, 5, and 6) in Ajax websites. The operational steps for each task included entering search keywords or choosing search parameters, and then finding the information reloaded in a section of the page. Due to the time limitation, participants were divided into two groups: ten participants were assigned to Tasks 1, 2, 3, and 4, and eight participants were assigned to Tasks 2, 5, and 6.

Table 1.  Task description for Experiment 1
Task numberTask descriptionSet A (N = 10)Set B (N = 8)
1Search for the actor 
2Search for the home appliance product information
3Search for your house on a map 
4Search for the real estate 
5Search for the hotel 
6Search for the restaurant 


Of the ten participants who were assigned to Tasks 1, 2, 3, and 4, two participants could not execute Task 4 due to the time limitation; therefore, only eight participants' Task 4 data were analyzed.

Participants' behavioral and verbal data were transcribed from video data, and problems were identified. Operation errors and task incompletion were extracted as the problems. Operation errors occurred when operations deviated from their correct course; the most efficient and the shortest operational steps to complete each task had been defined as the correct operation prior to the experiment. Task incompletion was when participants could not continue the task and asked for help.

From the results, we found fifteen problems throughout Tasks 1–6. Of the fifteen, two problems were attributed to the essential features of Ajax. The other thirteen problems found in Tasks 1–6 were fairly regular web usability problems, such as unrecognizable link designs and inadequate guidance messages. These are commonly observed in regular web usability tests and will not be discussed further in this study.

Problem 1 Inability to notice the result is displayed.  Six participants in Task 4, three participants in Task 5, and one participant in Task 6 did not notice when the result was displayed. Two error patterns were observed. The first pattern is that, on choosing a set of parameters, participants clicked a link button unrelated to the task and looked at the search result area, even though the search result had already been displayed on the same page they were looking at. Another pattern was that, after choosing a set of parameters, participants kept staring at the wrong area of the page, aiming to find the search result. A small reloading icon was displayed in the results section, but no participant said that they had noticed it. Detailed behavior is described in Figure 1.

Figure 1.

Errors observed in problem 1.

Problem 2 Inability to select tabs to look for search parameters.  To complete Task 6 (Restaurant Search), participants had to choose a set of parameters such as “Omotesandou-station” and “noodles” to find the restaurant that matched the search criteria. The search parameters were grouped using four tabs: “area”, “station”, “food”, and “preferences”. To find the restaurant, participants had to move from one tab to another and to choose the set of search parameters.

Five participants did not select any tabs. Consequently, they could not narrow down the results. After the task, participants said they did not realize that there were tabs. Detailed behavior is described in Figure 2.

Figure 2.

Errors observed in problem 2.


In tasks where problem 1 (the inability to notice the result was displayed) was extracted, the search parameter area and the result area were separate on the screen. Immediately after selecting search parameters, a small reloading icon emerged for a few seconds in the result area, and the new result was displayed. Participants later remarked that they did not notice any changes in the result area while they were selecting search parameters. Harada and Akatsu (2003) reported, in their comparative study of older and younger adult performance, that the older adults tend to overlook any changes in information on the screen. It is possible that under certain conditions it becomes difficult for older adults to shift their attention from search parameters to the result area. Problem 1 showed that the presentation of a standard Ajax reloading icon was not visible enough to draw the attention of the participants who were focusing on the search parameter section.

To complete Task 6, in which problem 2 (the inability to select tabs to look for search parameters) was extracted, participants had to choose a set of parameters, such as “Omotesandou-station” and “noodles,” to find the target restaurant. The correct operation was to click the “food” tab and to select the search parameter “noodles,” and the restaurant that matched the task description would be displayed in the result area along with three or four other restaurants. Participants who experienced problem 2 failed to click the “food” tab. To narrow down the results, participants had to look for possible links; however they failed to find the links on the screen. According to Suzuki, Motomiya, Hara, Sutou, Satou, Kumada, and Kitajima (2009), older adults with an age-related cognitive decline in selective attention had more difficulty in finding a link on a screen that had many elements.

Problem 2 indicated that the tab design in the website of task 6 was not discernible enough for the older adults. On the website used for Task 6, various links were closely arranged by the tab area. Even though these links were unrelated to the task, the crowded layout might have lowered the participants' ability to discern tabs from other elements. Ajax website design suffers from constraints associated with its functionality features. In particular, layout constraints (meaning sections of search parameters and results must be separated) require users to shift their focus constantly between two areas. Consequently, various parameters have to be arranged within the limited space, which often creates “layout crowdedness” in the search parameter area. This makes it even harder for users to understand the operating procedure of search parameters.

Problems 1 and 2 were caused by the fact that participants could only focus on one specific area of the page, but not on the other critical area. The websites used in Experiment 1 did not provide sufficient visual cues to steer the participants' focus to the right elements or sections. To solve these problems, more visible reloading icons and more distinctive tabs must be designed.

Experiment 2

The purpose of Experiment 2 was to examine the following design solutions for the problems found in Experiment 1. First, by minimizing elements such as guidance and links around a tab, and applying a distinctive graphical design to the tab to make it stand out on the screen, we aimed to convey clear visual messages to direct the older adults to where they could select search parameters (tabs). Second, a large reloading icon that covers almost all the result area was designed. The first solution aimed to promote participants' smooth tab operation. The second solution was designed to make participants aware of the result area.


Participants.  Ten older adults ranging in age from 60 to 70 years old (seven women and three men, average age 69.5 years) were recruited from the local senior personnel centre. The screening conditions were the same as for Experiment 1.

Apparatus and procedure.  The apparatus and procedure were the same as for Experiment 1.

Materials.  An Ajax prototype of a stock price search (version 1.0) made by the authors was presented to the participants. The following graphical design solutions were applied to the prototype, as illustrated in Figure 3. The first solution was to make the tab area B distinguishable by eliminating the visual noise around the tabs. The second solution was to design a large page-reloading icon that occupied areas A and C. These two design solutions were applied to the prototype (version 1.0), along with the specifications for a typical commercial stock price search website.

Figure 3.

Prototype (version 1.0).

Tasks.  Three tasks were assigned to the participants. These tasks were designed to evaluate the solutions applied to the prototype.

  • 1 Task 1: Search for the stock price of a specific construction company.
  • 2 Task 2: Search for the medical company whose stock price has risen the most recently.
  • 3 Task 3: Search for the service business company whose stock price has risen the most recently.


Problem 3 Inability to understand which search parameters are currently selected.  Six participants could not complete Task 2 because they could not remember the parameters they had selected. Participants were asked to find the stock price of a certain company in Task 1 and then to find another company's stock price in Task 2. All they needed to do in Task 2 was to change only one parameter (the industry); however, participants repeatedly changed one tab and then another, returned to the top page by using the back button of the browser, and then gave up. Detailed behavior is described in Figure 4.

Figure 4.

Errors observed in problem 3.


All participants realized when the new information had been reloaded. After looking at the search results, participants narrowed down the search parameters to obtain the result that matched the task descriptions. For the tabs, all participants successfully selected one tab and then another to look for the search parameters they wanted. No participant showed difficulty in finding the tabs this time. The results suggested that the two solutions made in the prototype (designing more visible page-reloading cues and more distinguishable tabs) are effective in solving the problems found in Experiment 1. The page-reloading visual cue was designed to occupy the entire result section. Even though participants were focusing on the search parameter area, it seemed that the change happening in the result area caught their attention. The tab area was designed so that it stood out most on the page, by minimizing the “visual noise” around it. For example, the elements that are unnecessary for basic operation were arranged at the lower part of the page. This attempt successfully drew the participants' visual attention to the tab area and helped them to understand the search operation procedure.

A new problem (problem 3) was found in this experiment: “Inability to understand which search parameters are currently selected.” Even though both the website in Task 6 (in Experiment 1) and the prototype (version 1.0) used tabs in the search parameter area, the operational steps of selecting search parameters were slightly different. On the website used for Task 6, if a participant wanted to change a search parameter within a tab, all he/she had to do was to click a new search parameter, which automatically deselected the previously selected parameter. In contrast, the prototype (version 1.0) required different operational steps in order to follow the specifications of the typical stock price website.

This prototype allowed the user to select only one of a predefined set of option buttons; participants first needed to reclick the selected search parameter they wanted to deselect, and then a new search parameter become available for selection.

To complete Task 2, the following cognitive steps should have occurred.

  • 1 Find the “Medical” (search parameter) under the industry tab.
  • 2 Realize that the “Medical” (search parameter) is not currently selectable.
  • 3 Recognize the need to change the “Medical” parameter to selectable status.
  • 4 Think of possible ways to select “Medical”; “Construction” has been selected in the previous task and has to be deselected.
  • 5 Find the operational steps to deselect “Construction” (either click “Reset” or click “Construction” again).

Participants who experienced problem 3 seemed to have difficulty in proceeding to the fourth step. Participants repeatedly moved between the tabs to look for why they could not select “Medical,” but they could not come up with the answer. In order to understand the reason for not being able to select “Medical,” it is thought that participants need to remember their operations for the previous task. However, it appeared that they could not remember the operations. It is possible to assume that this phenomenon is related to working memory. Considering that the primary cause of this problem is the unsuccessful retrieval of previous task operations, this phenomenon is interpreted as resulting from an age-related decline in episodic memory. Similar findings have been reported from the Web-Accessibility Empirical Study Office (2002), which found that, while engaged in complicated tasks, the older adults tended to forget the results of operations that they had performed immediately before. Tabs made it impossible for users to see all search parameters at the same time, because the search parameters under unselected tabs were hidden. It is thought that the fact that participants were unable to see the selected search parameters at the same time interfered with remembering that “Construction” had been selected previously.

The tab expression and lower visibility of the current setting area was considered to be the primary cause of problem 3. To solve problem 3, search parameters that can be seen at the same time and more recognizable current setting areas must be designed.

Experiment 3

The purpose of Experiment 3 was to examine design solutions for the problems found in Experiment 2. First, instead of tabs, all search parameters were designed in list form. Compared to tabs that hide search parameters under unselected tabs, a list makes it easier to see the search parameters all at once. Second, the selected search parameter areas were graphically designed to stand out more than other areas. Both solutions were aimed at making it easier for the participants to confirm and recall selected parameters visually.


Participants.  Six older adults ranging in age from 60 to 75 years old (three women and three men, average age 71.5 years) were recruited from a local senior personnel centre. The screening conditions were the same as for Experiments 1 and 2. Because the purpose of Experiment 3 was to evaluate the effects of design improvements applied to prototype 2, it was considered that five participants should be set as the minimum number of participants, based on the previous study (Nielsen, 1994).

Apparatus and procedure.  The apparatus and procedure were the same as for Experiments 1 and 2.

Materials.  An improved prototype of the stock price search website (version 2.0) was made by the authors. On the basis of the results of Experiment 2, the graphical design of the search parameter selection B and the visibility of the current setting area C were improved, as illustrated in Figure 5.

Figure 5.

Prototype (version 2.0).

Tasks.  The tasks assigned to the participants were the same as for Experiment 2.


Five participants completed the tasks without errors. One participant who could not complete the task displayed difficulties in understanding the general concept of stock and could not correctly understand the task explained by the experimenter. The results indicated that designing the search parameters so that users could capture everything at a glance, and raising the visibility of the current setting area, was effective in enhancing users' awareness of which parameters were currently selected.


The results supported the idea that listing search parameters made it easier for participants to understand which parameters were selected and which were not selected. Participants occasionally looked at the current setting area to make sure the right search parameters were selected, which confirmed that the improved design of the current setting area in the prototype (version 2.0) was visible enough for the participants. The results of Experiment 3 show that designing search parameters in a way that users can see everything all at once and designing an eye-catching current setting area contributed to solving problem 3. Harada (2006) argued that it is difficult for older adults to learn new systems while they are operating those systems. While younger adults can learn how to use the system while they are using it, older adults are not good at doing so. Episodic memory plays an important role in learning something that they do not already know (Tulving, 2002). The reason that older adults often have difficulty in learning new systems can be explained by the degraded episodic memory caused by aging. Craik (2000) suggested that episodic memory performance can be enhanced in older people by providing supportive contextual material at encoding and retrieval. It is assumed that the eye-catching current setting area was effective in providing the contextual material of encoding, and an eye-catching current setting area and search parameters in a list form supported the retrieving course of operation taken by older adults.


The goal of this study was to specify the usability problems of RIA websites for older adults and to design solutions for them. Three usability problems were identified through three experiments.

Problem 1 was the “inability to notice the result is displayed.” After setting some search parameters, the search results were simultaneously displayed next to the search parameter areas on the webpage. However, participants paid attention only to the search parameter areas and did not notice the results. Problem 2 was the “inability to select tabs to look for search parameters.” Participants were supposed to click tabs to set a few other search parameters, but they were not able to find the tabs because they paid attention only to the search parameter areas on one tab displayed at the beginning.

These two problems indicate that older adults tend to fail to find the target information that exists in front of them when they pay attention to other areas on the same page. Suzuki, Motomiya, Kashimura, Sutou, Satou, Kumada, and Kitajima (2008) reported similar findings. In their study, older adults with selective attention degradation exhibited difficulty in shifting attention successfully from remote controls to TV screens when using TV menus.

Age-related cognitive decline in the selective attention of older adults can be considered a potential reason for the two problems found in Experiment 1. Websites where problem 1 was found displayed a reloading icon before the search results appeared, but this icon was very small and disappeared very quickly. Moreover, participants paid attention only to the search parameter areas and did not notice reloading in another area on the page. In problem 2, the tabs were not distinct enough to be found when participants paid attention to the search parameters on a specific tab. When we try to find specific information efficiently, we need to ignore irrelevant or distracting information and to pay attention to the relevant information to achieve our aims. Older adults tend to have their attention taken by salient stimulus on webpages compounded from multiple areas, such as search parameters, search results, current settings, etc., and cannot shift their attention to the relevant information, such as reloaded search results or tabs. The compounded webpage with RIA must provide users visual or auditory cues that lead them to the important information (Rogers, 2000). The results in Experiment 2 indicate larger reloading icons and more distinct tab graphics can help older adults to shift their attention to relevant information to achieve their goals.

Problem 3 was the “inability to understand which search parameters are currently selected.” It is considered that the participants were not able to remember their operations for the previous task. Younger adults can generally accomplish a task without problems if the procedure is almost the same as the one for the previous task. However, older adults often have trouble doing so. Degraded episodic memory caused by aging is considered to be the primary cause of this problem. The results in Experiment 2 suggest that older adults facing compound stimulus can find it hard to remember even a short procedure consisting of only two or three steps.

One possible design solution for these problems caused by degraded episodic memory as a result of aging is to show the operations they have performed more visibly on the page. The webpage in Experiment 3 was revised in order to show the users' current settings more distinctively, and to provide a list of all search parameters, which can be read through without switching tabs. The results for Experiment 3 indicate the effectiveness of this design solution.

This study illustrates that there is a possibility that highly interactive new technologies, such as RIA, which enhances usability for younger adults, can pose problems for older adults with age-related decline in cognitive function. However, the results of the three experiments also suggest that we can prevent new technology from spoiling the IT experiences of older adults if we design web applications while keeping in mind possible degradation of selective attention or episodic memory with aging.

This study showed that the following three design strategies used for two prototypes were effective for older adults: (a) to increase the perceptual salience of the graphical user interface (GUI) elements or areas that are reloaded; (b) to highlight the status of current settings; (c) to avoid tabs and use a list, which enables users to look at all parameter categories at a glance. However, these are not always effective in every case. For example, in another usability study, the authors found a similar problem in which users did not notice a GUI element and revised the prototype so that the element became more eye-catching. This revision improved the performance of the task related to the element, but degraded the performance of another task related to another elements on the same screen. This happened because making one element stands out means reducing the salience of other elements on the same screen. The features of GUI elements are related to each other, so web designers have to balance the salience between the elements on a screen.

This study revealed that design changes indicated by the findings in the laboratory can improve the usability of a GUI for older adults, but may lead to another cognitive problem. Usability testing with realistic tasks and materials showed us some cases of how older adults face difficulties related to cognitive aging in everyday life, and how design changes can affect their performance in design practice.

In addition, the present study might introduce further research topics for episodic memory and selective attention from an industrial practitioner's point of view. The basic mechanism of selective attention and episodic memory has resulted in understanding the problems that older adults face while using new technology. However, for example, more information about successful cases of retrieval and attention shifting under complex and unfamiliar environments will be needed for designing new technology. It is important that researchers in cognitive psychology and industrial practitioners work together to understand the basic mechanism of age-related cognitive decline and its impact on everyday behaviors.