Assisting people with disabilities improves their collaborative pointingefficiency with a Multiple Cursor Dynamic Pointing Assistive Program

Ching-Hsiang Shih a,*, Ching-Tien Shih b, Shun-Kuang Wang 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 Country 82941, Taiwan, ROC

In many social environments (such as school), people are often required to communicate and work collaboratively. Co-located collaboration allows people to conduct direct face-to-face interactions, to see each other’s expressions and gestures,and therefore communicate more effectively (Bricker, Tanimoto, Rothenberg, Hutama, & Wong, 1995). Some research hasillustrated that multi-users could conduct co-located collaboration through a single computer with multiple input devices(Pal, Pawar, Brewer, & Toyama, 2006; Pawar, Pal, Gupta, & Toyama, 2007; Pawar, Pal, & Toyama, 2006; Stanton & Neale,2003), with each individual using their own input device (such as Pocket PC, and mouse) to improve motivation,effectiveness of task completion (through cooperative work), equity of activity, and reduction of time spent on any particulartask (Stanton & Neale, 2003; Stanton, Neale, & Bayon, 2002).

Stewart, Bederson, and Druin (1999) proposed the collaborative interaction model Single Display Groupware (SDG), inwhich a small group of co-located users are provided with their individual input device (can be simultaneously used), toenable them to collaborate, play, work, and share one computer with a single display (Stewart et al., 1999; Tse & Greenberg,2004). This notion of supporting multi-user co-located interaction through a shared display has been explored in manypapers (Scott, Mandryk, & Inkpen, 2003; Stewart et al., 1999). These SDG systems have been used quite successfully forchildren’s collaboration; besides this, many researches have been conducted on the advantages of SDG in school learning(Abnett, Stanton, Neale, & O’Malley, 2001; Pawar et al., 2007; Pawar et al., 2006; Stanton & Neale, 2003; Stanton et al., 2002;Tse & Greenberg, 2004).

However, the co-located collaborative technologies (SDG) mentioned above are focused on persons without disabilities.Concerning people with disabilities, this technology may not be suitable for them, and they cannot benefit from the SDGfunction, because (a) most of them usually encounter difficulties using a computer in a pointing operation (Cook & Hussey,

Research in Developmental Disabilities 31 (2010) 1251–1257

A R T I C L E I N F O

Article history:

Received 13 July 2010

Accepted 20 July 2010

Keywords:

Disabilities

Collaborative pointing

MCDPAP

Mouse driver

A B S T R A C T

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

minimal motor behavior would be able to improve their collaborative pointing

performance using finger poke ability with a mouse wheel through a Multiple Cursor

Dynamic Pointing Assistive Program (MCDPAP) with a newly developed mouse driver (i.e.,

a new mouse driver that replaces the standard mouse driver, changes a mouse wheel into a

thumb/finger poke detector, and intercepts/simulates mouse action). The study was

performed according to an ABAB design, in which A represented the baseline and B

represented intervention phases. Data showed that both groups of participants improved

their collaborative pointing ability through the use of MCDPAP during the intervention

phase. Practical and developmental implications of the findings are discussed.

� 2010 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 � 2010 Elsevier Ltd. All rights reserved.

doi:10.1016/j.ridd.2010.07.020

2002), and (b) SDG applications are targeted at the mainstream population, without providing the type of accommodationthat meets the needs or desires of people with disabilities (Stewart et al., 1999; Tse & Greenberg, 2004).

Some recent studies have adopted software technology to redesign the mouse driver in order to improve computeroperation performance of persons with disabilities: (a) multi-mice configuration; this research enabled physically disabledpeople to export the remaining ability of each limb with several mice to complete the mouse operation (Shih & Shih, 2009a,2009c), (b) Automatic Pointing Assistive Program (APAP) and Extended Automatic Pointing Assistive Program (EAPAP),where the user can click the mouse button when the cursor is near the target (inside the activation area), instead of movingthe cursor over the target (Shih, Hsu, & Shih, 2009; Shih, Li, Shih, Lin, & Lo, 2010), (c) Dual Cursor Automatic Pointing AssistiveProgram (DCAPAP) and Extended Dual Cursor Automatic Pointing Assistive Program (EDCAPAP), where the dual cursors (avirtual cursor and a system cursor) are adopted to offer users an operating environment with Mouseover effects, which iscloser to the real conditions (Shih, Chung, Chiang, & Shih, 2010; Shih, Shih, & Chiu, 2010), and (d) Automatic Drag-and-DropAssistive Program (ADnDAP), in which the complex dragging process (which is difficult or impossible for persons withdisabilities to operate) is replaced by a simple clicking operation with APAP function (Shih, Huang, Liao, Shih, & Chiang,2010). Shih, Cheng, Li, Shih, and Chiang (2010) extended the APAP function to SDG application, presented a Multiple CursorAutomatic Pointing Assistive Program (MCAPAP), to enable two people with disabilities to cooperate in pointing (Shih,Cheng, & et al., 2010). Each user has his own virtual cursor with APAP function (i.e., each user can click their mouse buttonwhen the virtual cursor is near the target).

All the researches mentioned above use software technology to improve pointing performance, focus on persons withdisabilities who can operate a mouse to move a computer cursor, but had very low mouse operation efficiency. Concerningpersons with disabilities who cannot easily or possibly use a computer through a standard mouse (such as people who haveextensive paralysis of their body and who can effectively control a computer only through very limited movements), theseresearches may not be suitable for them. Therefore, Shih, Chang, and Shih (2009) used a mouse wheel as a pointing assistivedevice to improve the pointing performance of people with multiple disabilities, who have minimal motor behavior, througha new operation method, the Dynamic Pointing Assistive Program (DPAP), where the user can poke his/her thumb/finger torotate a mouse wheel to move a cursor to a target (Shih, Chang, & et al., 2009).

This study extending the DPAP research, combined with Dual Cursor technology (Shih, Chung, & et al., 2010) toimplement the function of DPAP with SDG technology, proposed a new operation method, the Multiple Cursor DynamicPointing Assistive Program (MCDPAP), where driver technology is adopted to enable each user to have his own virtual cursorwith DPAP function (i.e., each user can rotate a mouse wheel by poking it with their thumb/finger, to move a cursor to atarget), to enable people with disabilities to collaboratively point, as shown in Fig. 1.

Fig. 1(a) shows a system cursor, two virtual cursors in different colors (blue and pink) with name prompts (Mark andJenny), and five pre-defined targets noted as P1, P2, P3, P4 and P5. Each user has a mouse, and each mouse controls a virtualcursor (such as Mark). The users poking the mouse wheel will quickly move the virtual cursor among the five targets. Thesystem cursor is over P4 (Pa position), and does not move with mouse movement. As soon as the mouse wheel is rotated, itsaction will be intercepted by MCDPAP, and the virtual cursor will automatically jump to a series of pre-defined targetpositions (i.e., P1–P5) in order, according to the amount of wheel rotation and direction. Each forward poke will jump thevirtual cursor from one to the next target in the order of P1! P2! P3! P4! P5! P1! . . ., whereas, a backward pokejumps the virtual cursor in the order of P5! P4! P3! P2! P1! P5! . . .. The more the poke amount is, the more thevirtual cursor jumps. All of the mouse (controlling virtual cursor) can be used simultaneously without interference. As shownin Fig. 1(b), when Jenny clicks (at P2 position), the system cursor will jump from its previous location (Pa) to Jenny’s virtualcursor position (P2) automatically (its movement path is shown by the red dashes) and perform the click to send functionalcommands to the computer. If Mark clicks (at P4 position), the system cursor will jump from its newest previous location(P2) to the location of Mark’s virtual cursor (P4) and perform the click (Fig. 1(c)). In this study, because any slight andundesired mouse movement could be detected by the precise mouse optical sensor, deviating the cursor from the target, themouse movement function is cancelled in order to avoid positioning interference. In this way, the traditional pointingsoftware, which only supports a single cursor for a single user to operate, can support people with disabilities with SDGfunction and pointing assistance (DPAP) without being modified or rewritten.

Though the computer techniques can support more than one mouse, windows operation system (OS) only supports oneuser (one cursor) to operate with the system. Once multiple mice are connected to a computer, the Windows OS will installits driver automatically, defining its function as a moving cursor. The cursor movement is the sum of all the operations of themice connected. As a result, it is not easy to modify the mouse default functions and simulate multiple virtual cursors to meetthe needs of MCDPAP.

Normally, the device driver (such as mouse and keyboard) is provided by Windows OS or the hardware manufacturer toensure that the connected device can function properly (Wikipedia, 2009). Redesigning a mouse driver can reset the mousefunctions, turning it into a much more powerful tool, but it is rarely proposed by researchers because of the complexity of thetechnology required and in-depth understanding of how the hardware and the software of a given platform function. Only afew recent researches have adopted software technology to redesign the mouse driver, visualizing the mouse as a useful toolfor many applications dedicated to persons with disabilities (Shih, Chiu, & et al., 2010; Shih & Shih, 2009b, 2009c, 2009d,2010; Shih, Shih, Lin, & Chiang, 2009), providing them with additional choices in assistive technology.

This work adopts new mouse driver design (i.e., a new mouse driver replaces a standard mouse driver, and is able to resetmouse default functions, change a mouse wheel into a thumb/finger poke detector, and intercepts/simulates mouse action)

C.-H. Shih et al. / Research in Developmental Disabilities 31 (2010) 1251–12571252

[(Fig._1)TD$FIG]

Fig. 1. The operation flow of Multiple Cursor Dynamic Pointing Assistive Program (MCDPAP). (a) A system cursor, two virtual cursors in different colors

(blue, pink) with name prompts (Mark, Jenny), and five pre-defined targets (P1–P5). Each user (Mark, Jenny) has a mouse, and each mouse controls a virtual

cursor. The system cursor is over P4 (Pa position), and does not move with mouse movement. As soon as the mouse wheel is rotated, its action will be

intercepted by MCDPAP, and the virtual cursor (such as Mark) will automatically jump to a series of pre-defined target positions (i.e., P1–P5) in order,

according to the wheel rotation amount and direction. Each forward poke will jump the virtual cursor from one target to the next in order of

P1! P2! P3! P4! P5! P1! . . ., whereas, a backward poke jumps the virtual cursor in order of P5! P4! P3! P2! P1! P5! . . .. All of the mouse

(controlling virtual cursor) can be used simultaneously without interference. (b) When Jenny clicks (at P2 position), the system cursor will jump from its

previous location (Pa) to Jenny’s virtual cursor position (P2) automatically (its movement path is shown by the red dashes) and perform the click. (c) If Mark

clicks (at P4 position), the system cursor will jump from its newest previous location (P2) to the location of Mark’s virtual cursor (P4) and perform the click.

(For interpretation of the references to colour 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) 1251–1257 1253

to help two groups of persons with disabilities who cannot easily or possibly use a standard mouse improve theircollaborative pointing efficiency, and to compare the difference of their collaborative pointing performance before and afterfor their use of MCDPAP, in order to determine whether the MCDPAP implementation can enhance their pointingperformance.

1. Methods

1.1. Participants

The participants (Tsai, Chen, Li, and Hwang) were 18, 13, 17 and 16 years of age, respectively. All of them have multipledisabilities. Tsai and Chen were the first group. Tsai’s level of function was rated as middle-level intellectual disability andpresented with profound muscle atrophy. Chen was rated in middle-level intellectual disability and had congenitalcerebropathy. Li and Hwang were the second group. Both of their levels of function were estimated to be in the middle rangeof intellectual disability, and had congenital cerebropathy. All participants had limited hand physical control ability, butcould still use a standard mouse with their right hands (Li used the left hand) in a laborious manner, and could not use amouse for a long time. They had very low mouse operation efficiency due to poor hand–eye coordination, lack of fine motorskills and low motivation induced by frustration. They were interested in computer operation, and hoped that they could usethe mouse more easily, quickly and accurately. Neither one had visual disabilities that could hinder them from using amouse, and could understand simple orders and perform the corresponding tasks.

With the guidance of the research assistant, all of them learned to poke their thumb/finger on the mouse wheel to movethe virtual cursor to targets and perform the click. Their parents had given formal consent for their involvement in thisexperiment.

1.2. Apparatus and setting

The study was carried out in an activity room of the special education school for the mentally retarded. Computers wereplaced on a computer table, and the screen was at a distance of about 30 cm from their chairs. Logitech wireless mice wereprovided to the participants when the experiment began.

1.3. MCDPAP setting, computer pointing test software

Four Logitech wireless mice which were installed with MCDPAP to detect the thumb/finger poke were placed under Tsai’s,Chen’s and Hwang’s right hand, and Li’s left hand. Movement function of all mice was cancelled, in order to avoidinterference.

A pointing test software with two modes (namely practice mode and record mode), which only supports a single user wasdesigned in this study to provide mouse pointing practice for participants (practice mode), and to record their pointing testresults (record mode, record participants’ successful pointing number within a certain period of time).

Fig. 2 presents the flow diagram of the computer pointing test software. Eight circular destination targets (noted T1–T8)with radii of 0.25 cm, were set every 458 on a circle with a radius of 6 cm.

In practice mode, the computer first displayed all destination targets (T1–T8), and set the mouse cursor to the centralpoint (Tc, the centre of the circumference). The participants had to move the system cursor from the centre point (Tc) to eachtarget, and then click to complete a successful pointing. When a task (a successful pointing) was completed, thecorresponding target disappeared, and the computer automatically set the system cursor back to the centre point (Tc).Participants would then move the system cursor to another target, and click on it. The eight targets reappeared until all thetargets were successfully pointed to and had disappeared. This process was repeated until the end of the practice time.

Test mode was run under the same conditions as the practice mode, but the successful pointing number within 3 min wasrecorded automatically by this program.

1.4. Experimental conditions

Initially, both groups of participants received an ABAB sequence (Richards, Taylor, Ramasamy, & Richards, 1999), in whichA represented the baseline phase (without MCDPAP technology) and B represented the intervention phase (with MCDPAPtechnology). Three to five sessions per day occurred within those study periods. Sessions lasted 18 min and were conductedat the participants’ school.

The arrangement of this 18-min session was as follows:

(a) Pointing practice (10 min)

All destination targets (T1–T8) appeared, and participants (group 1, group 2) move the system cursor to the targets andclicked. A research assistant provided vocal prompting and guidance during the practice session to help the participants tocomplete pointing tasks.

C.-H. Shih et al. / Research in Developmental Disabilities 31 (2010) 1251–12571254

(b) Rest (5 min)

Participants were given 5-min rest after practice.

(c) Assessment (3 min)

Same conditions as the practice mode, but neither vocal prompting nor instructions from the research assistant wereavailable. The number of times that each group of participants successfully pointed within 3 min was recorded as input forassessment.

1.4.1. Baseline phases

The baseline phase included 15 and 24 sessions, respectively. In this phase, the MCDPAP function was turned off, so theparticipants had to move the cursor from the central point (Tc) to the targets (T1–T8) to click. The movement of the systemcursor was the sum of the movement of both mice, which made it difficult for the two participants to avoid interference andcomplete the pointing test.

1.4.2. Intervention phases

This phase included 60 and 57 sessions, respectively. Procedural conditions were as during baseline except that theMCDPAP function was turned on. With the assistance of MCDPAP, both participants could move their own virtual cursor(through mouse wheel poking) together and click the mouse button when the virtual cursor was aimed at the target, insteadof moving the system cursor to the target.

Both groups’ successful pointing number within 3 min were recorded as input for assessment, and then used to determinewhether MCDPAP had improved their collaborative pointing abilities.

[(Fig._2)TD$FIG]

Fig. 2. The flow diagram of the computer pointing test software. Eight circular destination targets (noted T1–T8) with radii of 0.25 cm, were set every 458 on

a circle with a radius of 6 cm. The computer first displayed all destination targets (T1–T8), and set the mouse cursor to the central point (Tc, the centre of the

circumference). The participants had to move the system cursor from the centre point (Tc) to each target, and then click to complete a successful pointing.

When a task (a successful pointing) was completed, the corresponding target disappeared, and the computer automatically set the system cursor back to the

centre point (Tc). Participants would then move the system cursor to another target, and click on it. The eight targets reappeared until all the targets were

successfully pointed to and had disappeared.

C.-H. Shih et al. / Research in Developmental Disabilities 31 (2010) 1251–1257 1255

2. Results

Figs. 3 and 4 indicated the pointing speed of both groups in different phases. The curve showed that both groups improvedtheir pointing efficiency after the implementation of MCDPAP.

2.1. First group (Tsai and Chen)

The data of the first group was shown in Fig. 3. In the baseline phase, due to (a) they cannot easily operate a standardmouse (only having minimal motor skills), and (b) both mice will interfere with each other (the cursor movement is the sumof all the operations of the two mice). Therefore, they had very poor pointing performance during the first baseline phase (15sessions), only had a mean of about 2.2 pointing speed per minute. In the intervention phase, MCDPAP function worked, andparticipants could cooperate to point to targets (using thumb/finger poking mouse wheel) easily, and accurately. This meanpointing speed largely increased to 17.53 during the first intervention phase (60 sessions) and dropped to 3.83 during thesecond baseline phase (24 sessions). This mean pointing speed fully restored and eventually increased during the secondintervention phase (57 sessions). The differences of pointing speed between the baseline and the intervention weresignificant (p< .01) on the Kolmogorov–Smirnov test (Siegel & Castellan, 1988).

2.2. Second group (Li and Hwang)

The data of the second group was shown in Fig. 4. During the first baseline phase (15 sessions), poor pointing performancewith a mean of about 0.73 was raised because of interference and physical limitations. The mean largely increased to 18.55during the first intervention phase (60 sessions). This mean pointing speed dropped to 0.50 during the second baseline phase(24 sessions) to be fully restored and eventually increased during the second intervention phase (57 sessions). Thedifferences of pointing speed between the baseline and the intervention were significant (p< .01) on the Kolmogorov–Smirnov test (Siegel & Castellan, 1988).

3. Discussion

As the demand for collaborative applications grows, cooperative learning is a priority in many classrooms and has beenemphasized by current curriculum standards (NCTM, 1989). Concerning people with disabilities, it is very important forthem to have a collaborative working/learning chance in computer operation. The study presented in this paper addressed

[(Fig._4)TD$FIG]

Fig. 4. The pointing speed data of the second group (Li and Hwang). Data points represent the mean of successful points per minute per session over blocks of

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

[(Fig._3)TD$FIG]

Fig. 3. The pointing speed data of the first group (Tsai and Chen). Data points represent the mean of successful points per minute per session over blocks of

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

C.-H. Shih et al. / Research in Developmental Disabilities 31 (2010) 1251–12571256

this problem, and presents an effective way (using mouse wheel poking) to allow two people with multiple disabilities tocollaborate using a shared computer display.

As shown in this study, with the assistance of MCDPAP technology, which combines the advantages of virtual cursor andDPAP functions to give effective assistance, people with disabilities who generally encounter mouse operation problemsincrease significantly in their pointing level, and can cooperate to point to targets quickly, easily, and accurately.

This MCDPAP software-based solution can support all standard interfaces of commercial input devices (such as mouse andtrackball) that are compatible with the computer, including USB, wireless, and Bluetooth interfaces. It is also compatible with allcurrently available software, so existing software can be utilized to support multiple people with disabilities face-to-faceinteracting in a co-located environment, to improve the collaborative pointing efficiency, without being modified or rewritten.

Both groups of participants rapidly improved their collaborative pointing efficiencies after receiving MCDPAP. The resultsof this study demonstrate that people with disabilities can easily master MCDPAP without long-period practice. Theseparticipants could cooperate in using many educational/CAI software, which only support a single cursor for a single user tooperate through MCDPAP after the experiment.

This study only considers collaborative pointing, focusing on individuals with disabilities, who can neither use a standardmouse to point nor perform collaborative pointing efficiently. Further studies are necessary to develop additional mouseapplications to extend current functionality (such as collaborative dragging) and satisfy the needs of different levels ofdisabilities. Hopefully, the implementation of MCDPAP can realize collaboration in all complex mouse operations andprovide persons with disabilities with additional choices in computer assistive technology.

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