Assisting people with developmental disabilities improve theircollaborative pointing efficiency with a Multiple Cursor AutomaticPointing Assistive Program

Ching-Hsiang Shih a,*, Hsiao-Fen Cheng a, Chia-Chun Li a, Ching-Tien Shih b,Ming-Shan Chiang a

a Department of Special Education, National Dong Hwa University, Hualien, Taiwan, ROCb Department of Electronics Engineering and Computer Science, Tung-Fang Institute of Technology, Kaohsiung County, Taiwan, ROC

There is a growing population of individuals who are motivated to use a computer but find it physically difficult to do so,particularly when using a pointing device such as a mouse. One of the main reasons computers are inaccessible to theseindividuals is that they treat all users the same, and usually do not accommodate a user’s unique needs, especiallyconcerning persons with disabilities. Based on this, various modifications and adaptations of computer-pointing deviceshave been proposed to meet the needs of people with multiple disabilities (Brodwin, Star, & Cardoso, 2004; Hedrick, Pape,Heinemann, Ruddell, & Reis, 2006; Mann, Belchior, Tomita, & Kemp, 2005; Shein, Treviranus, Brownlow, Milner, & Parnes,1992; Tu, Tao, & Huang, 2007). Except these special assistive input devices, Shih and Shih (2009a, 2009c) presented a multi-mouse configuration in order to enable people with physical disabilities to perform mouse operation through using theremaining ability of each limb with several mice to offer them the opportunity to use a standard mouse, like people withoutdisabilities.

Common pointing problems include inability to select small targets, difficulty moving a pointing device in a straight line,or difficulty controlling the pointer’s buttons. Many researchers have also studied assistive programs to facilitate the qualityof pointing (target positioning/acquiring) operation, in order to improve the operation ability of people with disabilities(Ahlstrom, 2005; Ahlstrom, Hitz, & Leitner, 2006; Akamatsu & MacKenzie, 2002; Casiez, Vogel, & Balakrishnan, 2008;Cockburn & Brewster, 2005; Cockburn & Firth, 2003; Dennerlein & Yang, 2001; Grossman & Balakrishnan, 2005; Park, Han, &Yang, 2006). These studies have characterized pointing performance in terms of movement trajectories, accuracy, clickingbehaviors and speed. Users can benefit from being provided useful functions in pointing, such as moving the cursor to the

Research in Developmental Disabilities 31 (2010) 600–607

A R T I C L E I N F O

Article history:

Received 1 December 2009

Accepted 18 December 2009

Keywords:

Developmental disabilities

Collaborative pointing

MCAPAP

Mouse driver

A B S T R A C T

This study evaluated whether four persons (two groups) with developmental disabilities

would be able to improve their collaborative pointing performance through a Multiple

Cursor Automatic Pointing Assistive Program (MCAPAP) with a newly developed mouse

driver (i.e., a new mouse driver replaces standard mouse driver, and is able to intercept/

simulate mouse action). The study was performed according to an ABAB design, in which A

represented baseline and B represented intervention phases. Data showed that both

groups of participants improved their collaborative pointing ability through the use of

MCAPAP during the B (intervention) phase. Practical and developmental implications of

the findings are discussed.

� 2009 Elsevier Ltd. All rights reserved.

* Corresponding author. Tel.: +886 3 8227106x1320; fax: +886 3 8228707.

E-mail address: schee@mail.ndhu.edu.tw (C.-H. Shih).

Contents lists available at ScienceDirect

Research in Developmental Disabilities

0891-4222/$ – see front matter � 2009 Elsevier Ltd. All rights reserved.

doi:10.1016/j.ridd.2009.12.012

target centre automatically, and to position the target quickly, easily, and accurately (Grossman & Balakrishnan, 2005; Parket al., 2006).

Recent studies (Shih, Chang, & Shih, 2009; Shih, Chung, Chiang, & Shih, 2010; Shih, Hsu, & Shih, 2009; Shih, Huang, Liao,Shih, & Chiang, 2009) adopted software technology to redesign the mouse driver in order to improve computer operationperformance: (a) Automatic Pointing Assistive Program (APAP), where the user can click the mouse button when the cursoris near the target (inside the activation area), instead of moving the cursor to the target, to improve the users’ pointingefficiency (Shih, Hsu et al., 2009). (b) Dual Cursor Automatic Pointing Assistive Program (DCAPAP), where the dual cursors (avirtual cursor and a system cursor) are adopted to offer users an operating environment which is closer to the real conditions(Shih et al., 2010). (c) Dynamic Pointing Assistive Program (DPAP), where the people with multiple disabilities who haveminimal motor skill can poke his/her thumb/finger to rotate a mouse wheel to move a cursor to a target (Shih, Chang et al.,2009). (d) Automatic Drag-and-Drop Assistive Program (ADnDAP), where the complex dragging process is replaced bysimple clicking operation when the cursor is near the target (Shih, Huang et al., 2009). These software-based mouse driverapproaches are powerful because they can reset mouse functions and enable a standard mouse to adapt to needs of peoplewith disabilities and work across applications.

Co-located collaboration allows students to interact directly, see each other’s expressions and gestures, and thereforecommunicate more effectively (Bricker, Tanimoto, Rothenberg, Hutama, & Wong, 1995). There is some evidence that co-located users could collaborate through a single computer with multipoint or multiple mouse technology (Pal, Pawar,Brewer, & Toyama, 2006; Pawar, Pal, Gupta, & Toyama, 2007; Pawar, Pal, & Toyama, 2006; Stanton & Neale, 2003), eachindividual using their own mouse, to improve motivation, effectiveness of task completion (through parallel or co-operativework), equity of activity, and reduce the time on task (Stanton, Neale, & Bayon, 2002; Stanton & Neale, 2003).

Therefore, single-display groupware (SDG) was proposed to enable a small group of co-located users to collaborate, work,and share one computer with a single display, and simultaneously use multiple input devices (Stewart, Bederson, & Druin,1999; Tse & Greenberg, 2004). With SDG, multiple co-located persons, with their individual input device, can interactsimultaneously on a single communal display, thereby multiplying the amount of interaction per student per PC for the costof only a few extra mice (Pawar et al., 2007). This is highly attractive for schools in developing countries where realizing highstudent–computer ratio is a common problem. SDG solutions have also been used to create software for disadvantagedchildren, particularly in the developing world (Pawar et al., 2006, 2007), and allow for greater utilization of the limitedinfrastructure available to these kids. Besides this, many researches have been conducted on the advantages of SDG in schoollearning (Abnett et al., 2001; Pawar et al., 2006, 2007; Stanton et al., 2002; Stanton and Neale, 2003; Tse and Greenberg,2004).

As mentioned above, though many researches have been proposed to develop SDG application, all these solutions havelimitations because SDG faces challenges in working with legacy applications (Heimerl, Ramachandran, Pal, Brewer, &Parikh, 2009; Hutterer & Thomas, 2007). Though the computer techniques can support more than one mouse, windowsoperation system (OS) only supports a single cursor for a single user to operate. Mouse control is the sum of all the operationsof the mice connected, so the existing software would not benefit or would have to be rewritten in order to have SDG function(Hourcade, Perry, & Sharma, 2008).

Only few researches have worked on utilizing SDG with legacy educational software. However, they have their applicablelimitations and have difficulties in matching well with legacy software (Heimerl et al., 2009; Hutterer and Thomas, 2007;Shoemaker & Inkpen, 2000). Besides, most SDG are targeted at the mainstream population, without providing the type ofaccommodation that meets the needs or desires of people with disabilities.

Fig. 1(a) shows a ‘‘Whack a Ground Hog’’ game (TechRadium, 2009), which, as is most software, is designed for a singleuser. People with disabilities cannot well operate these programs or they have low operation ability due to their physicallimitations. The benefits are obvious if people with disabilities could make advantage of SDG and APAP functions to operatethis game. As shown in Fig. 1(b), three virtual cursors in different colors with name promptings (Mark, Bill and Jenny) arecontrolled by three mice. They can be used simultaneously without interference. In addition, each virtual cursor has APAPfunction (Shih, Hsu et al., 2009), and the user can click the mouse button when the cursor is near the target (inside theactivation area), instead of moving it to the target. However, it is very difficult to modify the existing legacy software(Fig. 1(a)) to possess SDG function (Fig. 1(b)) in the existing Windows OS, and this is rarely proposed in the field concerningpersons with disabilities.

It can be achieved through a new revised operation method, Multiple Cursor Automatic Pointing Assistive Program(MCAPAP), where driver technology is adopted to enable each user have his own virtual cursor with APAP function (i.e., eachuser can click their mouse button when the virtual cursor is near the target), to enable people with disabilities to point withthe assistance of SDG, as shown in Fig. 2. Fig. 2(a) shows a system cursor, two virtual cursors in different colors (blue, pink)with name prompting (Mark, Jenny), and two target buttons (B1, B2) with activation areas (A1, A2) of MCAPAP. Each user hasa mouse, and each mouse controls a virtual cursor. The system cursor is over B1, and does not move with mouse movement.As shown in Fig. 2(b), when Mark clicks inside B1s activation area (A1), the system cursor will jump from its previous location(over B1) to B1 centre automatically (its movement path is shown by the red dashes) and perform the click. He does not haveto move his virtual cursor over the target (B1), but can click inside its activation area (A1). If Jenny clicks outside B2’sactivation area (A2), the system cursor will jump from its previous location (B1 centre) to the location of Jenny’s virtualcursor and perform the click (Fig. 2(c)). When Jenny clicks inside B2’s activation area, the system cursor will jump to B2centre and perform the click.

C.-H. Shih et al. / Research in Developmental Disabilities 31 (2010) 600–607 601

In this way, the traditional pointing software which only supports a single cursor can support people with disabilitieswith SDG function and pointing assistance (APAP), without being modified or rewritten. The key technology of MCAPAP isthe mouse action interception and simulation, without which users can neither intercept mouse action nor simulatemultiple cursor action.

Every hardware device linked to a computer requires a software-based driver to work normally. Writing a device driverrequires an in-depth understanding of how the hardware and the software of a given platform function. Normally, the devicedriver is provided by Windows OS or the hardware manufacture, to ensure that the connected device can function properly(Wikipedia, 2009b). Driver modification is rarely proposed by researchers because of the complexity of the technologyrequired (Microsoft, 2008a, 2008b; Wikipedia, 2009b). Only recent researchers (Shih, Chang et al., 2009; Shih, Hsu et al.,2009; Shih, Huang et al., 2009; Shih, Shih, Lin, & Chiang, 2009; Shih et al., 2010; Shih & Shih, 2009a, 2009b, 2009c, 2009d, inpress) adopted software technology to redesign the mouse driver in order to reset mouse functions, and made the mouse auseful tool for many applications dedicated to persons with disabilities, providing them with additional choices in assistivetechnology.

As a standard device for computers, once multiple mice are connected to a computer, the cursor movement is the sum ofall the operations of the mice connected. As a result, it is not easy to intercept all mouse action and simulate multiple cursors,and no research which adopts driver technology to utilize SDG with legacy software for people with disabilities is publishedin this field.

This work adopts Shih’s new revised mouse driver (action intercepting driver) design (i.e., a new mouse driver replaces astandard mouse driver, and is able to intercept/simulate mouse action) to help two groups of persons with developmentaldisabilities improve their collaborative pointing efficiency, and to compare the difference of their collaborative pointingperformance before and after for their use of MCAPAP, in order to determine whether the MCAPAP implementation canenhance their pointing performance.

Fig. 1. A ‘‘Whack a Ground Hog’’ game (TechRadium, 2009). (a) This game is designed for a single user. People with disabilities cannot operate it well, or they

have low operation ability due to their physical limitations. (b) Three virtual cursors in different colors with name promptings (Mark, Bill and Jenny) were

controlled by three mice. They could be used simultaneously without interference.

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1. Method

1.1. Participants

The participants (Tsai, Chen, Li, & Hwang) were 18, 13, 17 and 16 years of age, respectively. Tsai and Chen were the firstgroup. Tsai’s level of function was estimated to be in the profound range of intellectual disability, and with hereditarychromosomal abnormalities. Chen was rated in middle-level intellectual disability with autism, psychological disorders,Attention Deficit Hyperactivity Disorder (ADHD) and epilepsy. Li and Hwang were the second group. Li’s levels of functionwere estimated to be in the middle range of intellectual disability. Hwang’s level of function was estimated to be in theprofound range of multiple disabilities. All participants could use the common mouse with their right hands, but their poorhand–eye coordination resulted in poor mouse operation ability. They were interested in computer operation, and none hadvisual disabilities that could be problematic in using a mouse. With the guidance of the research assistant, all of them learnedto move the mouse cursor to targets and perform the click. Their parents had given formal consent for their involvement inthis experiment.

The first group (Tsai and Chen) participated in the DCAPAP experiment (Shih, Chung et al., 2009). Tsai used to encounterdifficulties when operating the mouse because of his small hand size. Usually, his disability caused him to click both the leftand right buttons at the same time. Chen had very low mouse operation efficiency since his fingers could not extend, but he

Fig. 2. The operation flow of Multiple Cursor Automatic Pointing Assistive Program (MCAPAP). (a) A system cursor, two virtual cursors in

different colors (blue, pink) with name promptings (Mark, Jenny), and two target buttons (B1, B2) with activation areas (A1, A2) of MCAPAP.

Each user has a mouse, and each mouse controls a virtual cursor. The system cursor is over B1, and does not move with mouse movement. (b)

When Mark clicks inside B1’s activation area (A1), the system cursor will jump from its previous location (over B1) to B1 centre automatically (its

movement path is shown by the red dashes) and perform the click. He does not have to move his virtual cursor over the target (B1), but can click

inside its activation area (A1). (c) When Jenny clicks outside B2’s activation area (A2), the system cursor will jump from its previous location (B1

centre) to the location of Jenny’s virtual cursor and perform the click. (d) When Jenny clicks inside B2s activation area, the system cursor will jump to

B2 centre and perform the click. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the

article.)

C.-H. Shih et al. / Research in Developmental Disabilities 31 (2010) 600–607 603

had no difficulty in mouse operation because the mouse shape matched well with his hand curve. He could perform a click,but clicked the right button with middle finger occasionally.

The second group (Li and Hwang) had little mouse operation experience and needed to hold a rotated mouse. They couldmove a mouse and click mouse button. With the guidance of the research assistant, they learned when they had to click buthad very low mouse operation efficiency due to poor hand coordination, and could not use a mouse for an extended period oftime.

1.2. Apparatus and setting

The study was carried out in an activity room. Computers were placed on a computer table, and the screen was at adistance of about 30 cm from their chairs. Wireless mice were provided for the participants when the experiment began.

1.3. MCAPAP setting, computer mouse test software

This study designed a pointing test software which only supports a single user to record participants’ successful pointswithin a certain period of time.

Fig. 3 presents the flow diagram of the computer mouse pointing test software. Eight circular destination targets (T1–T8)with radii of 0.25 cm, were set every 458 on a circle with a radius of 5 cm. Each target had a circular area with a radius of1.5 cm as the activation area (A1–A8) of the MCAPAP. When the participants clicked the mouse button inside this circularactivation area, mouse click action would be intercepted as soon as the mouse was clicked, the cursor would jump to thetarget center automatically, and the intercepted mouse click action would be sent out. The computer first displayed alldestination targets (T1–T8). The participants had to move the mouse cursor to each target, then click to complete a successfulpointing. When a task (a successful pointing) was completed, the corresponding target disappeared. Participants would thenmove the mouse cursor to another target, and click on it. The eight targets reappeared until all the targets were successfullypointed to and had disappeared. This process was repeated until the end of test time. Times of successful pointing within3 min were recorded automatically by this program.

1.4. Experimental conditions

Initially, both groups of participants received an ABAB sequence, in which A represented the baseline phase (withoutMCAPAP technology) and B represented the intervention phase (with MCAPAP technology). Three to five sessions per dayoccurred within those study periods. Sessions lasted 3 min and were conducted at school. The number of successful pointswithin 3 min were recorded automatically.

Fig. 3. The flow diagram of the computer mouse pointing test software. Eight circular destination targets (T1–T8), each with a radius of 0.25 cm, were set

every 458 on a circle with a radius of 5 cm. Each target has a circular area with a radius of 1.25 cm as the activation area (A1–A8) of MCAPAP.

C.-H. Shih et al. / Research in Developmental Disabilities 31 (2010) 600–607604

1.4.1. Baseline phases

The baseline phase included 30 and 36 sessions, respectively. In this phase, neither SDG nor MCAPAP function worked. Atthe beginning of these sessions, participants received promptings to move the mouse cursor to each target, and then clickedto complete a successful pointing. The movement of the system cursor was the sum of the movement of both mice, whichmade it difficult for the two participants to avoid interference and complete the pointing test.

1.4.2. Intervention phases

This phase included 60 and 36 sessions, respectively. Procedural conditions were as during baseline except that theMCAPAP function was turned on, and both participants could point together and click the mouse button when the cursor wasnear the target (inside the activation area), instead of moving the cursor to the target, to improve the users’ pointing ability(Shih, Hsu et al., 2009).

Both groups’ successful points within 3 min were recorded as input for assessment, and then used to determine whetherMCAPAP improved their pointing abilities.

2. Results

Figs. 4 and 5 indicated the pointing speed of both groups in different phases. The curve showed that both groups improvedtheir pointing efficiency after the implementation of MCAPAP. The data of the first group was shown in Fig. 4. During the firstbaseline phase (30 sessions), they had poor pointing performance due to interference (i.e., Tsai was interfered duringpositioning because Chen moved his mouse). They had a mean of about 1.9 pointing speed per min. This mean pointing speedlargely increased to 23.1 during the first intervention phase (60 sessions) and dropped to 3.78 during the second baselinephase (18 sessions). This mean pointing speed fully restored and eventually increased during the second intervention phase(42 sessions). The differences of pointing speed between the baseline and the intervention were significant (p< .01) on theKolmogorov–Smirnov test (Siegel & Castellan, 1988).

The data of the second group was shown in Fig. 5. During the first baseline phase (36 sessions), poor pointing performancewith a mean of about 0.78 was raised because of interference. The mean increased to 30.31 during the first interventionphase (36 sessions). This mean pointing speed dropped to 1.22 during the second baseline phase (18 sessions) to be fullyrestored and eventually increased during the second intervention phase (42 sessions). The differences of pointing speedbetween the baseline and the intervention were significant (p< .01) on the Kolmogorov–Smirnov test (Siegel & Castellan,1988).

Fig. 5. The pointing speed data of the second group (Li and Hwang). Data points represent the mean of successful points/min/session over blocks of three

sessions. Only the final points of a phase can represent a block of two sessions.

Fig. 4. The pointing speed data of the first group (Tsai and Chen). Data points represent the mean of successful points/min/session over blocks of three

sessions. Only the final points of a phase represent a block of two sessions.

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3. Discussion

It is very important for people with disabilities to have a collaborative working chance in computer operation. As shownin this study, with the assistance of MCAPAP, which combines the advantages of SDG and APAP functions to give effectiveassistance, people with developmental disabilities increase significantly in their pointing level, and can cooperate to point totargets quickly, easily, and accurately. On one hand, MCAPAP maintains the benefits of APAP to avoid cursor deviation (Shih,Hsu et al., 2009) through its compatibility with all standard commercial pointing devices (i.e., mouse and trackball) includingUSB, wireless, and Bluetooth (Wikipedia, 2009a) interfaces. On the other hand, it is also compatible with all currentlyavailable software, so existing software solutions can be utilized to improve the pointing efficiency of people withdisabilities, without being modified or rewritten.

Both groups of participants greatly improved their collaborative pointing efficiencies after receiving MCAPAP. Analyticalresults demonstrate that people with developmental disabilities can easily master MCAPAP without long-period practice.These participants could cooperate in using some educational/CAI software which require pointing operation throughMCAPAP after the experiment.

This study only considers collaborative pointing, focusing on individuals with developmental disabilities, who canneither use a standard mouse to point nor perform collaborative pointing efficiently. Further studies are necessary to developadditional mouse applications to extend current functionality (i.e., collaborative dragging) and satisfy the needs of differentlevels of disabilities. Hopefully, the implementation of MCAPAP can realize collaboration in all complex mouse operationsand provide persons with disabilities with additional choices in computer assistive technology.

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