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Two persons with multiple disabilities use orientation technology with auditory cues to manage simple indoor traveling
Research in Developmental Disabilities 31 (2010) 397–402
Contents lists available at ScienceDirect
Research in Developmental Disabilities
Two persons with multiple disabilities use orientation technology with auditory cues to manage simple indoor traveling Giulio E. Lancioni a,*, Nirbhay N. Singh b, Mark F. O’Reilly c, Jeff Sigafoos d, Francesca Campodonico e, Doretta Oliva e a
Department of Psychology, University of Bari, Via Quintino Sella 268, 70100 Bari, Italy ONE Research Institute, Midlothian, VA, USA Meadows Center for Preventing Educational Risk, University of Texas at Austin, TX, USA d Victoria University of Wellington, Wellington, New Zealand e Lega F. D’Oro Research Center, Osimo (AN), Italy b c
A R T I C L E I N F O
A B S T R A C T
Article history: Received 4 October 2009 Accepted 6 October 2009
This study was an effort to extend the evaluation of orientation technology for promoting independent indoor traveling in persons with multiple disabilities. Two participants (adults) were included, who were to travel to activity destinations within occupational settings. The orientation system involved (a) cueing sources only at the destinations (i.e., a single sound source per destination), (b) a newly developed electronic control device that allowed the participants to easily manage the activation of the sources at the destinations, and (c) the provision of approval or encouragement messages. Both participants were successful in using the system and performed their travels to the destinations fairly correctly and in relatively short amounts of time within (a) the occupational setting used for the intervention and (b) a similar occupational setting used for checking generalization effects. The findings are discussed in relation to the importance of independent indoor traveling and the impact of the new technology. ß 2009 Elsevier Ltd. All rights reserved.
Keywords: Orientation technology Auditory cues Indoor traveling Travel speed Multiple disabilities
1. Introduction Persons with blindness and other disabilities, such as neuromotor and intellectual impairments, may encounter serious orientation and mobility problems even within their homes and occupational/vocational places (Joffee & Rikhye, 1991; Lancioni, Mantini, O’Reilly, & Oliva, 1999; Lancioni, Oliva, & Bracalente, 1995a; Lancioni, Oliva, & Bracalente, 1995b; Uslan, Malone, & De l’Aune, 1983; Uslan, Russell, & Weiner, 1988). These problems can have serious negative implications in terms of activity engagement, personal independence, self-assurance, and, ultimately, quality of life (Algozzine, Browder, Karvonen, Test, & Wood, 2001; Draheim, Williams, & McCubbin, 2002; Gee, Harrell, & Rosenberg, 1987; Lachapelle et al., 2005; Lancioni, Gigante, O’Reilly, Oliva, & Montironi, 2000; Petry, Maes, & Vlaskamp, 2005). Teaching these persons to develop maps of their daily indoor areas using miniature replicas of those areas or some landmarks as orientation cues may occasionally lead to successful outcomes (Lancioni, O’Reilly, Oliva, & Bracalente, 1998; Lancioni et al., 2007). In general, however, (a) the information provided by miniature replicas of the real environments is difficult to generalize effectively and (b) the discrimination of the landmarks and their association with different activities and travel directions may be very demanding (Bentzen, 1977; Blasch, Welsh, & Davidson, 1973; Dodds,
* Corresponding author. E-mail address: [email protected] (G.E. Lancioni). 0891-4222/$ – see front matter ß 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.ridd.2009.10.002
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G.E. Lancioni et al. / Research in Developmental Disabilities 31 (2010) 397–402
Howarth, & Carter, 1982; Joffee, 1995; Joffee & Rikhye, 1991; Lancioni & Oliva, 1999; Martinsen, Tellevik, Elmerskog, & Storlilokken, 2007). A potentially effective alternative to the aforementioned maps could be the use of orientation technology and, more specifically, orientation systems relying on auditory direction cues (Lancioni et al., 1995a, 2007; Uslan et al., 1988). These systems are intended to guide (direct) the persons to the destinations without requiring them to possess special spatial/ traveling abilities other than orienting/walking to the sound sources that provide direction cues (Lancioni et al., 2007, 2008). While these systems can be quite useful, efforts are definitely needed to enhance their flexibility and simplicity so that they can more easily suit different environmental and personal situations (Scherer, Sax, Vanbiervliet, Cushman, & Scherer, 2005). Recently, a system was set up which involved (a) cueing sources only at the destinations (i.e., a single sound source per destination), thus it was simplified compared to previous systems, and (b) a portable, electronic control device with keys that the participants used to activate those sources/destinations. Both participants (adults with multiple disabilities) were successful in using the system and improved their traveling (Lancioni et al., 2008). The present study assessed an adapted version of such a system with two new participants (women) with total blindness and moderate or moderate-to-severe intellectual disability, who were to use the system to travel to activity destinations within familiar occupational settings. Contrary to the participants of the aforementioned study (Lancioni et al., 2008), the two women could not discriminate and use the keys of the control device in the available form. To deal with this problem, a larger control device with wider/different key areas was developed. These key areas, which served for activating the destinations, consisted of embedded optic sensors covered with small (discriminated) objects representing the activities available at the destinations. By removing/detaching an object for an activity (i.e., uncovering the underlying optic sensor), the participant triggered the sound source at the corresponding activity destination. A second technical change (novelty) consisted of equipping the system with the function of providing approval or encouragement messages to the participants during the sessions. This function was deemed important to automatically ensure conditions similar to those to which the participants were used. 2. Method 2.1. Participants The participants (Nelly and Lucille) were 24 and 21 years old, respectively, and presented with total blindness and intellectual disabilities due to congenital abnormalities or perinatal hypoxia with subsequent encephalopathy. Psychological reports placed them in the moderate intellectual disability area (Nelly) or moderate-to-severe intellectual disability range (Lucille). Moreover, they showed substantial delays in terms of daily living abilities as well as communication and social interaction. The Vineland Adaptive Behavior Scales—Interview Edition (Sparrow, Balla, & Cicchetti, 1984) showed age equivalents of about 3 years on Daily Living Skills and Socialization and near 4 years on Communication for Nelly. Lucille’s age equivalents were below 3 years on Daily Living Skills and below 2 years on Communication and Socialization. Both participants were known for their orientation problems and their reliance on staff for reaching relevant destinations within their daily contexts. Both attended a day activity center where they engaged in simple occupational and vocational activities such as assembling or dividing/disassembling two-piece objects, putting away clothes, storing food products/items or other daily material. Nelly had verbalized her interest in participating in the study. Lucille could not do so directly but was reported to start the sessions eagerly. The parents of both participants had signed an informed consent form for the study. 2.2. Settings Two activity settings were used for each participant, one served as an intervention setting and the other as a generalization setting. The intervention setting, which was the same for the two participants, consisted of three rooms and an entrance/corridor section, which practically constituted a fourth room (for a total area of about 100 m2). Each of the three regular rooms included two to four destinations, that is, desks with familiar occupational and vocational activities such as those mentioned in the Participants section. The entrance/corridor contained one or two destinations with one or two additional activities. The doors of the rooms were regularly open. The generalization setting included five rooms with nine activity destinations, for an area of about 65 m2 (Nelly) and a single room with eight activity destinations, for an area of about 100 m2 (Lucille). The distances that the participants typically traveled to reach the destinations varied between 4 and 17 m. 2.3. Orientation system The orientation system included a sound source at each destination and a portable, electronic control device. The sources were battery-powered boxes, which contained a transceiver, an optic sensor, an amplified MP3 player with USB pen drive connection, and a pen drive. The pen drive contained recordings of (a) the orientation cues (i.e., combinations of the participant’s name with one or two other words such as ‘‘Over here, Nelly’’), and (b) verbal encouragement and verbal approval sentences (e.g., ‘‘Take an object, Lucille’’ or ‘‘Next activity, Lucille’’, and ‘‘Great job, Nelly’’). The electronic control device (a box of 20 cm 15 cm 4 cm that the participants had at their chest) involved a microprocessor with specific software, a transceiver, and six key areas of 6 cm 7 cm each. The keys corresponded to destinations (activities) that the
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participants had to reach during the session (see below). As mentioned above, each of the keys consisted of an embedded optic sensor (a photocell) covered with a small, discriminated object representing an activity available at one of the destinations. The object was fixed onto the key through Velcroß strips or small fasteners surrounding the sensor. As soon as a participant removed/detached an object for an activity (i.e., uncovering the underlying optic sensor), the device’s transceiver activated the sound source at the corresponding activity destination. The source emitted a cue every 15 s (i.e., a frequency deemed suitable for both participants) until the participant arrived at the destination and, specifically, until the participant triggered the optic sensor of the sound source available at the destination. Triggering the optic sensor also started a timing function. This function served to determine the occurrence of social approval (Nelly) or of encouragement/prompting messages (Lucille). Social approval was timed to occur 2 or 3 s after Nelly’s arrival at the destination (see above). Encouragement/prompting for Lucille would occur if she failed to start the sequence for a new activity (by selecting an object from the electronic control device) within about 90 s from reaching the current destination. If the participant accidentally detached two objects rather than one, the device activated only the source corresponding to the first object being removed. The research assistant would eventually replace the object not utilized onto the device so as to allow the participant to make use of it for traveling to the corresponding activity destination. 2.4. Experimental conditions Recording concerned (a) the participants’ travels to the target destinations and whether they were correct, that is, they occurred independent of the research assistant’s previous interventions for replacing the related/unutilized objects on the device (see above) or guidance during the sequence (see below); (b) the time required for the travels; and (c) the system-delivered encouragement messages for Lucille. Reliability was assessed in nearly 20% of the participants’ sessions. The percentages of interrater agreement (computed on the single measures for blocks of two sessions, by dividing the number of agreements by the total number of recordings and multiplying by 100) were within the 80–100 range, with means exceeding 95. Agreements on the times required for travels allowed 10-s discrepancy between raters. The study started with baseline (i.e., traveling without orientation system) in both settings. Then, an intervention phase (i.e., traveling with the orientation system) was carried out in the intervention setting. This phase was followed by a new baseline and a second intervention phase in the same setting, completing an ABAB design within that setting (Barlow, Nock, & Hersen, 2009). As an appendix to the second B of the aforementioned sequence, the orientation system was used in the generalization setting. Baseline and intervention phases involved three to nine sessions per day. Each session included six travels to as many destinations/activities. Prior to the sessions, a research assistant presented the participants the six (discriminated) objects signaling the six activities that they were expected to perform. The same objects were then attached (a) to the keys of the electronic control device tied onto their chest during intervention sessions (see above), or (b) to a simple board similar to the control device (also tied onto their chest) during baseline sessions. The six activities of the sessions were to be carried out according to the sequence that the participants decided to follow. 2.4.1. Baseline (A) phases During the baseline phases, the orientation system was not in use. The participants had a small board on their chest with the objects representing the activities for the session (see above). Prior to each travel, they would detach the object signaling the activity that they were going to engage in. Detaching two objects at the same time led to the research assistant replacing the one not utilized (i.e., as described in Section 2.3). To maintain conditions similar to those available prior to the study, Lucille found a small edible (motivating) item under the activity material at each destination and could receive verbal encouragements to continue with the activities, while Nelly would receive several instances of social approval through the sessions. Physical guidance from the research assistant was provided if the participants did not make any progress in starting or continuing the travel for over 1 min or did not complete it (reaching the destination) in 4 or 5 min. 2.4.2. Intervention (B) phases Intervention sessions differed from baseline sessions in that the orientation system, with sound sources and the electronic control device, was available. The participants received orientation cues as well as approval (Nelly) and encouragement (Lucille) messages (see Section 2.3), which allowed discontinuation of the corresponding messages provided by the researcher during baseline. Prior to each travel, the participants removed/detached from the control device the object signaling the activity they wanted to perform and this triggered the source at the destination as described above. The first intervention phase was introduced by three and seven practice sessions for Nelly and Lucille, respectively, which focused on the appropriate use of the electronic control device’s keys and on the orientation to the sound sources’ cues. 2.4.3. Generalization Generalization sessions were carried out in the generalization setting. Baseline conditions applied for the first three (Nelly) or five (Lucille) of those sessions carried out at the start of the study. Intervention conditions applied for the last 14 generalization sessions carried out at the end of the second intervention phase.
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3. Results Figs. 1 and 2 summarize the participants’ travel data, that is, the percentages of travels they carried out correctly/ independently and their travel speed (i.e., meters per minute computed from the travel times and distances). Nelly’s mean percentage of correct travels was about 10 during the first five baseline sessions in the intervention setting and about 20 during the three parallel sessions in the generalization setting (see Fig. 1). During this phase, her mean travel speed across the two settings was below 3 m/min. The mean percentage of correct travels during the first intervention phase (comprising 55 sessions) increased to above 90; and the mean travel speed was about 14 m/min. The mean percentage of correct travels and the mean travel speed declined very rapidly during the second baseline (comprising four sessions), and increased again to above 90 and 14 m/min during the second intervention phase (comprising 64 sessions). Matching percentages of correct travels with somewhat lower travel speed were also found during the final 14 generalization sessions (i.e., when the orientation system was used in the generalization setting). The Kolmogorov–Smirnov test (Siegel & Castellan, 1988) showed that the differences between baseline and intervention levels were statistically significant (p < .01) on both correct travels and travel speed. Lucille’s mean percentage of correct travels was below 10 during the first nine baseline sessions in the intervention setting and the five parallel sessions in the generalization setting (see Fig. 2). The mean travel speed was below 3 m/min. During the first intervention phase (47 sessions), the mean percentage of correct travels increased to about 85 and the mean travel speed increased to about 11 m/min. The two measures dropped during the second baseline (four sessions) and increased to above 90 and nearly 13 m/min during the second intervention phase (89 sessions). Both measures remained
Fig. 1. Nelly’s data. The black circles represent mean percentages of correct travels per session computed over blocks of three baseline or intervention sessions carried out in the intervention setting. Blocks of two sessions are indicated with an arrow. The empty circles represent mean percentages of correct travels per session over blocks of three or two sessions during the initial (baseline) and the final sessions carried out in the generalization setting. The black and empty triangles represent the mean travel speed (meters per minute) during the aforementioned blocks of sessions in the intervention and the generalization settings, respectively.
Fig. 2. Lucille’s data plotted as in Fig. 1.
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relatively high also during the final 14 sessions in the generalization setting. The differences between baseline and intervention levels were statistically significant (p < .01) for both measures on the Kolmogorov–Smirnov test. Systemdelivered encouragement messages had a mean of nearly two occurrences per session during the first intervention phase, but became fairly sporadic thereafter. 4. Discussion The results showed that the orientation system was effective with both participants in ensuring high percentages of correct, successful indoor travels and reducing the time required for the travels (i.e., increasing the travel speed) (Baldwin, 2003; Lancioni et al., 2007). These data extend previous evidence on the effectiveness of orientation technology and the possibility of generalizing its use across settings (Baldwin, 2003; Kazdin, 2001; Lancioni et al., 2007; Parker, 2009; Petry et al., 2005). With regard to the technology, two aspects seem to deserve particular/immediate attention, that is, (a) the reduced number of orientation sources used for the program, and (b) the new electronic control device that allowed the participants to easily manage the activation of the sources and determine their own activity engagement sequence. A third technical aspect that might also be noted is the availability of approval and encouragement messages. Relying on a reduced number of orientation sources may be considered a strategy with two practical advantages and one potential disadvantage. The advantages can be identified in the fact that the system (a) would be more easily applicable and transportable across settings (because of the fewer components involved and the simplicity with which one could arrange them) and (b) would be more economical thus more easily affordable across a larger number of contexts. The potential disadvantage concerns the fact that the level of orientation guidance provided is bound to be less specifically directive compared to situations in which multiple sources are used. Less specific orientation guidance may be less effective in helping persons with more severe orientation problems and lower intellectual functioning than the participants of this study (Guth & LaDuke, 1994, 1995; Lancioni et al., 2007). The availability of an electronic control device that can be used easily and effectively by the participants for activating the orientation sources is a basic requirement for promoting their independence in traveling across different places (cf. Baldwin, 2003; Martinsen et al., 2007). This independence would have wide positive implications for the participants’ activity engagement and social image, and great relevance for their general acceptance within the environment and eventually their quality of life (cf. Baldwin, 2003; Lancioni et al., 2007). The special key areas with optic sensors and small objects identifying the destinations/activities, developed for this study, seemed to be critical features for ensuring the successful performance of the participants. First, the participants could discriminate and operate the keys easily. Second, the object detached prior to each travel to an activity remained in the participants’ hands reminding them of the activity to which they were walking. Third, the display of the objects identifying the activities (i.e., on the key areas of the electronic control device) allowed the participants to have an overview of those activities at will and choose the activity engagement sequence with ease (Konrad, Fowler, Walker, Test, & Wood, 2007). The availability of the approval and encouragement/prompting functions may be considered an important asset of the new technology used in this study. Although no direct, formal evidence is available on their specific impact, it is very likely that the approval messages used for Nelly at her arrival at the destinations served as mild social reinforcers motivating her performance and maintaining a level of continuity with the environmental support/approval to which she was used. Probably, she could have become capable of performing without those messages or with few of them. If so, their presence would only have served to make Nelly’s engagement more enjoyable, improving the general atmosphere available for her without costs for staff (Kazdin, 2001; Lancioni et al., 2007; Petry et al., 2005; Zekovic & Renwick, 2003). The encouragement/ prompt messages arranged for Lucille seemed to have an effect on performance at least during the first intervention phase. Again, the data available do not prove that their presence was essential for the final outcome of the program. Yet, it seems safe to state that they helped Lucille learn to be successful and gain full independence with minimal costs for staff (Baldwin, 2003; Lancioni et al., 2008). In conclusion, this study has (a) provided additional evidence as to the importance of orientation technology for helping blind persons with additional disabilities to travel indoor successfully, (b) introduced relevant variations in terms of technology, with a new electronic control device and the availability of approval and encouragement functions, (c) pointed out the potential advantages of the technology package (and related new elements). It should be underlined that the reported technology and its potential advantages need to be viewed in relation to the characteristics of the present participants and not necessarily all participants (i.e., including those with profound intellectual disability). New research will need to (a) replicate the study carried out here with additional participants to verify the generality of the present findings and (b) assess new technology variations so as to prepare alternatives for a wide range of potential (different) users. References Algozzine, B., Browder, D., Karvonen, M., Test, D. W., & Wood, W. M. (2001). Effects of intervention to promote self-determination for individuals with disabilities. Review of Educational Research, 71, 219–277. Baldwin, D. (2003). Wayfinding technology: A road map to the future. Journal of Visual Impairment and Blindness, 97, 612–620. Barlow, D. H., Nock, M., & Hersen, M. (2009). Single-case experimental designs: Strategies for studying behavior change (3rd ed.). New York: Allyn & Bacon. Bentzen, B. L. (1977). Orientation maps for visually impaired persons. Journal of Visual Impairment and Blindness, 71, 193–196. Blasch, B. B., Welsh, R. L., & Davidson, T. (1973). Auditory maps: An orientation aid for visually handicapped persons. The New Outlook for the Blind, 67, 145–158.
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Dodds, A. G., Howarth, C. I., & Carter, D. C. (1982). The mental maps of the blind: The role of previous visual experience. Journal of Visual Impairment and Blindness, 76, 5–12. Draheim, C. C., Williams, D. P., & McCubbin, J. A. (2002). Prevalence of physical inactivity and recommended physical activity in community-based adults with mental retardation. Mental Retardation, 40, 436–444. Gee, K., Harrell, R., & Rosenberg, R. (1987). Teaching orientation and mobility skills within and across natural opportunities for travel. In L. Goetz, D. Guess, & K. Stremel-Campbell (Eds.), Innovative program design for individuals with dual sensory impairments (pp. 127–157). Baltimore: Brookes. Guth, D., & LaDuke, R. (1994). The veering tendency of blind pedestrians: An analysis of the problem and literature review. Journal of Visual Impairment and Blindness, 88, 391–400. Guth, D., & LaDuke, R. (1995). Veering by blind pedestrians: Individual differences and their implications for instruction. Journal of Visual Impairment and Blindness, 89, 28–37. Joffee, E. (1995). Approaches to teaching orientation and mobility. In K. M. Huebner, J. G. Prickett, T. R. Welch, & E. Joffee (Eds.), Hand in hand: Essentials of communication and orientation and mobility for your students who are deaf-blind (pp. 575–611). New York: AFB Press. Joffee, E., & Rikhye, C. H. (1991). Orientation and mobility for students with severe visual and multiple impairments: A new perspective. Journal of Visual Impairment and Blindness, 85, 211–216. Kazdin, A. E. (2001). Behavior modification in applied settings (6th ed.). New York: Wadsworth. Konrad, M., Fowler, C. H., Walker, A. R., Test, D. W., & Wood, W. M. (2007). Effects of self-determination interventions on the academic skills of students with learning disabilities. Learning Disability Quarterly, 30, 89–113. Lachapelle, Y., Wehmeyer, M. L., Haelewyck, M. C., Courbois, Y., Keith, K. D., Schalock, R., et al. (2005). The relationship between quality of life and selfdetermination: An international study. Journal of Intellectual Disability Research, 49, 740–744. Lancioni, G. E., Gigante, A., O’Reilly, M. F., Oliva, D., & Montironi, L. (2000). Indoor travel and simple tasks as physical exercise for people with profound multiple disabilities. Perceptual and Motor Skills, 91, 211–216. Lancioni, G. E., Mantini, M., O’Reilly, M. F., & Oliva, D. (1999). An adapted acoustic orientation system for promoting independent indoor travel and activity in persons with profound multiple disabilities. Journal of Developmental and Physical Disabilities, 11, 35–46. Lancioni, G. E., & Oliva, D. (1999). Using an orientation system for indoor travel and activity with persons with multiple disabilities. Disability and Rehabilitation, 21, 124–127. Lancioni, G. E., Oliva, D., & Bracalente, S. (1995a). An acoustic orientation system to promote independent indoor travel in blind persons with severe mental retardation. Perceptual and Motor Skills, 80, 747–754. Lancioni, G. E., Oliva, D., & Bracalente, S. (1995b). Comparison of two orientation systems for indoor travel of blind persons with mental retardation. Perceptual and Motor Skills, 81, 643–650. Lancioni, G. E., O’Reilly, M. F., Oliva, D., & Bracalente, S. (1998). Guiding a person with blindness and intellectual disability in indoor travel with fewer auditory cues. Journal of Visual Impairment & Blindness, 92, 609–614. Lancioni, G. E., O’Reilly, M. F., Singh, N. N., Sigafoos, J., Oliva, D., Bracalente, S., et al. (2007). Orientation systems to support indoor travel by persons with multiple disabilities: Technical aspects and application issues. Technology and Disability, 19, 1–6. Lancioni, G. E., Singh, N. N., O’Reilly, M. F., Sigafoos, J., Campodonico, F., & Oliva, D. (2008). Self-management of orientation technology and auditory cues for indoor travel by two persons with multiple disabilities. Journal of Developmental and Physical Disabilities, 20, 129–138. Martinsen, H., Tellevik, J. M., Elmerskog, B., & Storlilokken, M. (2007). Mental effort in mobility route learning. Journal of Visual Impairment and Blindness, 101, 327– 338. Parker, A. T. (2009). Orientation and mobility with persons who are deaf-blind: An initial examination of single-subject-design research. Journal of Visual Impairment and Blindness, 103, 372–377. Petry, K., Maes, B., & Vlaskamp, C. (2005). Domains of quality of life of people with profound multiple disabilities: The perspective of parents and direct support staff. Journal of Applied Research in Intellectual Disabilities, 18, 35–46. Scherer, M. J., Sax, C., Vanbiervliet, A., Cushman, L. A., & Scherer, J. V. (2005). Predictors of assistive technology use: The importance of personal and psychological factors. Disability and Rehabilitation, 27, 1321–1331. Siegel, S., & Castellan, N. J. (1988). Nonparametric statistics (2nd ed.). New York: McGraw-Hill. Sparrow, S. S., Balla, D. A., & Cicchetti, D. V. (1984). Vineland adaptive behavior scales: Interview edition survey form. Circle Pines, MN: American Guidance Service. Uslan, M., Malone, S., & De l’Aune, W. (1983). Teaching route travel to multiply handicapped blind adults: An auditory approach. Journal of Visual Impairment and Blindness, 77, 18–20. Uslan, M., Russell, L., & Weiner, C. (1988). A ‘musical pathway’ for spatially disoriented blind residents of a skilled nursing facility. Journal of Visual Impairment and Blindness, 82, 21–24. Zekovic, B., & Renwick, R. (2003). Quality of life for children and adolescents with developmental disabilities: Review of conceptual and methodological issues relevant to public policy. Disability and Society, 18, 19–34.
Contents lists available at ScienceDirect
Research in Developmental Disabilities
Two persons with multiple disabilities use orientation technology with auditory cues to manage simple indoor traveling Giulio E. Lancioni a,*, Nirbhay N. Singh b, Mark F. O’Reilly c, Jeff Sigafoos d, Francesca Campodonico e, Doretta Oliva e a
Department of Psychology, University of Bari, Via Quintino Sella 268, 70100 Bari, Italy ONE Research Institute, Midlothian, VA, USA Meadows Center for Preventing Educational Risk, University of Texas at Austin, TX, USA d Victoria University of Wellington, Wellington, New Zealand e Lega F. D’Oro Research Center, Osimo (AN), Italy b c
A R T I C L E I N F O
A B S T R A C T
Article history: Received 4 October 2009 Accepted 6 October 2009
This study was an effort to extend the evaluation of orientation technology for promoting independent indoor traveling in persons with multiple disabilities. Two participants (adults) were included, who were to travel to activity destinations within occupational settings. The orientation system involved (a) cueing sources only at the destinations (i.e., a single sound source per destination), (b) a newly developed electronic control device that allowed the participants to easily manage the activation of the sources at the destinations, and (c) the provision of approval or encouragement messages. Both participants were successful in using the system and performed their travels to the destinations fairly correctly and in relatively short amounts of time within (a) the occupational setting used for the intervention and (b) a similar occupational setting used for checking generalization effects. The findings are discussed in relation to the importance of independent indoor traveling and the impact of the new technology. ß 2009 Elsevier Ltd. All rights reserved.
Keywords: Orientation technology Auditory cues Indoor traveling Travel speed Multiple disabilities
1. Introduction Persons with blindness and other disabilities, such as neuromotor and intellectual impairments, may encounter serious orientation and mobility problems even within their homes and occupational/vocational places (Joffee & Rikhye, 1991; Lancioni, Mantini, O’Reilly, & Oliva, 1999; Lancioni, Oliva, & Bracalente, 1995a; Lancioni, Oliva, & Bracalente, 1995b; Uslan, Malone, & De l’Aune, 1983; Uslan, Russell, & Weiner, 1988). These problems can have serious negative implications in terms of activity engagement, personal independence, self-assurance, and, ultimately, quality of life (Algozzine, Browder, Karvonen, Test, & Wood, 2001; Draheim, Williams, & McCubbin, 2002; Gee, Harrell, & Rosenberg, 1987; Lachapelle et al., 2005; Lancioni, Gigante, O’Reilly, Oliva, & Montironi, 2000; Petry, Maes, & Vlaskamp, 2005). Teaching these persons to develop maps of their daily indoor areas using miniature replicas of those areas or some landmarks as orientation cues may occasionally lead to successful outcomes (Lancioni, O’Reilly, Oliva, & Bracalente, 1998; Lancioni et al., 2007). In general, however, (a) the information provided by miniature replicas of the real environments is difficult to generalize effectively and (b) the discrimination of the landmarks and their association with different activities and travel directions may be very demanding (Bentzen, 1977; Blasch, Welsh, & Davidson, 1973; Dodds,
* Corresponding author. E-mail address: [email protected] (G.E. Lancioni). 0891-4222/$ – see front matter ß 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.ridd.2009.10.002
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G.E. Lancioni et al. / Research in Developmental Disabilities 31 (2010) 397–402
Howarth, & Carter, 1982; Joffee, 1995; Joffee & Rikhye, 1991; Lancioni & Oliva, 1999; Martinsen, Tellevik, Elmerskog, & Storlilokken, 2007). A potentially effective alternative to the aforementioned maps could be the use of orientation technology and, more specifically, orientation systems relying on auditory direction cues (Lancioni et al., 1995a, 2007; Uslan et al., 1988). These systems are intended to guide (direct) the persons to the destinations without requiring them to possess special spatial/ traveling abilities other than orienting/walking to the sound sources that provide direction cues (Lancioni et al., 2007, 2008). While these systems can be quite useful, efforts are definitely needed to enhance their flexibility and simplicity so that they can more easily suit different environmental and personal situations (Scherer, Sax, Vanbiervliet, Cushman, & Scherer, 2005). Recently, a system was set up which involved (a) cueing sources only at the destinations (i.e., a single sound source per destination), thus it was simplified compared to previous systems, and (b) a portable, electronic control device with keys that the participants used to activate those sources/destinations. Both participants (adults with multiple disabilities) were successful in using the system and improved their traveling (Lancioni et al., 2008). The present study assessed an adapted version of such a system with two new participants (women) with total blindness and moderate or moderate-to-severe intellectual disability, who were to use the system to travel to activity destinations within familiar occupational settings. Contrary to the participants of the aforementioned study (Lancioni et al., 2008), the two women could not discriminate and use the keys of the control device in the available form. To deal with this problem, a larger control device with wider/different key areas was developed. These key areas, which served for activating the destinations, consisted of embedded optic sensors covered with small (discriminated) objects representing the activities available at the destinations. By removing/detaching an object for an activity (i.e., uncovering the underlying optic sensor), the participant triggered the sound source at the corresponding activity destination. A second technical change (novelty) consisted of equipping the system with the function of providing approval or encouragement messages to the participants during the sessions. This function was deemed important to automatically ensure conditions similar to those to which the participants were used. 2. Method 2.1. Participants The participants (Nelly and Lucille) were 24 and 21 years old, respectively, and presented with total blindness and intellectual disabilities due to congenital abnormalities or perinatal hypoxia with subsequent encephalopathy. Psychological reports placed them in the moderate intellectual disability area (Nelly) or moderate-to-severe intellectual disability range (Lucille). Moreover, they showed substantial delays in terms of daily living abilities as well as communication and social interaction. The Vineland Adaptive Behavior Scales—Interview Edition (Sparrow, Balla, & Cicchetti, 1984) showed age equivalents of about 3 years on Daily Living Skills and Socialization and near 4 years on Communication for Nelly. Lucille’s age equivalents were below 3 years on Daily Living Skills and below 2 years on Communication and Socialization. Both participants were known for their orientation problems and their reliance on staff for reaching relevant destinations within their daily contexts. Both attended a day activity center where they engaged in simple occupational and vocational activities such as assembling or dividing/disassembling two-piece objects, putting away clothes, storing food products/items or other daily material. Nelly had verbalized her interest in participating in the study. Lucille could not do so directly but was reported to start the sessions eagerly. The parents of both participants had signed an informed consent form for the study. 2.2. Settings Two activity settings were used for each participant, one served as an intervention setting and the other as a generalization setting. The intervention setting, which was the same for the two participants, consisted of three rooms and an entrance/corridor section, which practically constituted a fourth room (for a total area of about 100 m2). Each of the three regular rooms included two to four destinations, that is, desks with familiar occupational and vocational activities such as those mentioned in the Participants section. The entrance/corridor contained one or two destinations with one or two additional activities. The doors of the rooms were regularly open. The generalization setting included five rooms with nine activity destinations, for an area of about 65 m2 (Nelly) and a single room with eight activity destinations, for an area of about 100 m2 (Lucille). The distances that the participants typically traveled to reach the destinations varied between 4 and 17 m. 2.3. Orientation system The orientation system included a sound source at each destination and a portable, electronic control device. The sources were battery-powered boxes, which contained a transceiver, an optic sensor, an amplified MP3 player with USB pen drive connection, and a pen drive. The pen drive contained recordings of (a) the orientation cues (i.e., combinations of the participant’s name with one or two other words such as ‘‘Over here, Nelly’’), and (b) verbal encouragement and verbal approval sentences (e.g., ‘‘Take an object, Lucille’’ or ‘‘Next activity, Lucille’’, and ‘‘Great job, Nelly’’). The electronic control device (a box of 20 cm 15 cm 4 cm that the participants had at their chest) involved a microprocessor with specific software, a transceiver, and six key areas of 6 cm 7 cm each. The keys corresponded to destinations (activities) that the
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participants had to reach during the session (see below). As mentioned above, each of the keys consisted of an embedded optic sensor (a photocell) covered with a small, discriminated object representing an activity available at one of the destinations. The object was fixed onto the key through Velcroß strips or small fasteners surrounding the sensor. As soon as a participant removed/detached an object for an activity (i.e., uncovering the underlying optic sensor), the device’s transceiver activated the sound source at the corresponding activity destination. The source emitted a cue every 15 s (i.e., a frequency deemed suitable for both participants) until the participant arrived at the destination and, specifically, until the participant triggered the optic sensor of the sound source available at the destination. Triggering the optic sensor also started a timing function. This function served to determine the occurrence of social approval (Nelly) or of encouragement/prompting messages (Lucille). Social approval was timed to occur 2 or 3 s after Nelly’s arrival at the destination (see above). Encouragement/prompting for Lucille would occur if she failed to start the sequence for a new activity (by selecting an object from the electronic control device) within about 90 s from reaching the current destination. If the participant accidentally detached two objects rather than one, the device activated only the source corresponding to the first object being removed. The research assistant would eventually replace the object not utilized onto the device so as to allow the participant to make use of it for traveling to the corresponding activity destination. 2.4. Experimental conditions Recording concerned (a) the participants’ travels to the target destinations and whether they were correct, that is, they occurred independent of the research assistant’s previous interventions for replacing the related/unutilized objects on the device (see above) or guidance during the sequence (see below); (b) the time required for the travels; and (c) the system-delivered encouragement messages for Lucille. Reliability was assessed in nearly 20% of the participants’ sessions. The percentages of interrater agreement (computed on the single measures for blocks of two sessions, by dividing the number of agreements by the total number of recordings and multiplying by 100) were within the 80–100 range, with means exceeding 95. Agreements on the times required for travels allowed 10-s discrepancy between raters. The study started with baseline (i.e., traveling without orientation system) in both settings. Then, an intervention phase (i.e., traveling with the orientation system) was carried out in the intervention setting. This phase was followed by a new baseline and a second intervention phase in the same setting, completing an ABAB design within that setting (Barlow, Nock, & Hersen, 2009). As an appendix to the second B of the aforementioned sequence, the orientation system was used in the generalization setting. Baseline and intervention phases involved three to nine sessions per day. Each session included six travels to as many destinations/activities. Prior to the sessions, a research assistant presented the participants the six (discriminated) objects signaling the six activities that they were expected to perform. The same objects were then attached (a) to the keys of the electronic control device tied onto their chest during intervention sessions (see above), or (b) to a simple board similar to the control device (also tied onto their chest) during baseline sessions. The six activities of the sessions were to be carried out according to the sequence that the participants decided to follow. 2.4.1. Baseline (A) phases During the baseline phases, the orientation system was not in use. The participants had a small board on their chest with the objects representing the activities for the session (see above). Prior to each travel, they would detach the object signaling the activity that they were going to engage in. Detaching two objects at the same time led to the research assistant replacing the one not utilized (i.e., as described in Section 2.3). To maintain conditions similar to those available prior to the study, Lucille found a small edible (motivating) item under the activity material at each destination and could receive verbal encouragements to continue with the activities, while Nelly would receive several instances of social approval through the sessions. Physical guidance from the research assistant was provided if the participants did not make any progress in starting or continuing the travel for over 1 min or did not complete it (reaching the destination) in 4 or 5 min. 2.4.2. Intervention (B) phases Intervention sessions differed from baseline sessions in that the orientation system, with sound sources and the electronic control device, was available. The participants received orientation cues as well as approval (Nelly) and encouragement (Lucille) messages (see Section 2.3), which allowed discontinuation of the corresponding messages provided by the researcher during baseline. Prior to each travel, the participants removed/detached from the control device the object signaling the activity they wanted to perform and this triggered the source at the destination as described above. The first intervention phase was introduced by three and seven practice sessions for Nelly and Lucille, respectively, which focused on the appropriate use of the electronic control device’s keys and on the orientation to the sound sources’ cues. 2.4.3. Generalization Generalization sessions were carried out in the generalization setting. Baseline conditions applied for the first three (Nelly) or five (Lucille) of those sessions carried out at the start of the study. Intervention conditions applied for the last 14 generalization sessions carried out at the end of the second intervention phase.
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3. Results Figs. 1 and 2 summarize the participants’ travel data, that is, the percentages of travels they carried out correctly/ independently and their travel speed (i.e., meters per minute computed from the travel times and distances). Nelly’s mean percentage of correct travels was about 10 during the first five baseline sessions in the intervention setting and about 20 during the three parallel sessions in the generalization setting (see Fig. 1). During this phase, her mean travel speed across the two settings was below 3 m/min. The mean percentage of correct travels during the first intervention phase (comprising 55 sessions) increased to above 90; and the mean travel speed was about 14 m/min. The mean percentage of correct travels and the mean travel speed declined very rapidly during the second baseline (comprising four sessions), and increased again to above 90 and 14 m/min during the second intervention phase (comprising 64 sessions). Matching percentages of correct travels with somewhat lower travel speed were also found during the final 14 generalization sessions (i.e., when the orientation system was used in the generalization setting). The Kolmogorov–Smirnov test (Siegel & Castellan, 1988) showed that the differences between baseline and intervention levels were statistically significant (p < .01) on both correct travels and travel speed. Lucille’s mean percentage of correct travels was below 10 during the first nine baseline sessions in the intervention setting and the five parallel sessions in the generalization setting (see Fig. 2). The mean travel speed was below 3 m/min. During the first intervention phase (47 sessions), the mean percentage of correct travels increased to about 85 and the mean travel speed increased to about 11 m/min. The two measures dropped during the second baseline (four sessions) and increased to above 90 and nearly 13 m/min during the second intervention phase (89 sessions). Both measures remained
Fig. 1. Nelly’s data. The black circles represent mean percentages of correct travels per session computed over blocks of three baseline or intervention sessions carried out in the intervention setting. Blocks of two sessions are indicated with an arrow. The empty circles represent mean percentages of correct travels per session over blocks of three or two sessions during the initial (baseline) and the final sessions carried out in the generalization setting. The black and empty triangles represent the mean travel speed (meters per minute) during the aforementioned blocks of sessions in the intervention and the generalization settings, respectively.
Fig. 2. Lucille’s data plotted as in Fig. 1.
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relatively high also during the final 14 sessions in the generalization setting. The differences between baseline and intervention levels were statistically significant (p < .01) for both measures on the Kolmogorov–Smirnov test. Systemdelivered encouragement messages had a mean of nearly two occurrences per session during the first intervention phase, but became fairly sporadic thereafter. 4. Discussion The results showed that the orientation system was effective with both participants in ensuring high percentages of correct, successful indoor travels and reducing the time required for the travels (i.e., increasing the travel speed) (Baldwin, 2003; Lancioni et al., 2007). These data extend previous evidence on the effectiveness of orientation technology and the possibility of generalizing its use across settings (Baldwin, 2003; Kazdin, 2001; Lancioni et al., 2007; Parker, 2009; Petry et al., 2005). With regard to the technology, two aspects seem to deserve particular/immediate attention, that is, (a) the reduced number of orientation sources used for the program, and (b) the new electronic control device that allowed the participants to easily manage the activation of the sources and determine their own activity engagement sequence. A third technical aspect that might also be noted is the availability of approval and encouragement messages. Relying on a reduced number of orientation sources may be considered a strategy with two practical advantages and one potential disadvantage. The advantages can be identified in the fact that the system (a) would be more easily applicable and transportable across settings (because of the fewer components involved and the simplicity with which one could arrange them) and (b) would be more economical thus more easily affordable across a larger number of contexts. The potential disadvantage concerns the fact that the level of orientation guidance provided is bound to be less specifically directive compared to situations in which multiple sources are used. Less specific orientation guidance may be less effective in helping persons with more severe orientation problems and lower intellectual functioning than the participants of this study (Guth & LaDuke, 1994, 1995; Lancioni et al., 2007). The availability of an electronic control device that can be used easily and effectively by the participants for activating the orientation sources is a basic requirement for promoting their independence in traveling across different places (cf. Baldwin, 2003; Martinsen et al., 2007). This independence would have wide positive implications for the participants’ activity engagement and social image, and great relevance for their general acceptance within the environment and eventually their quality of life (cf. Baldwin, 2003; Lancioni et al., 2007). The special key areas with optic sensors and small objects identifying the destinations/activities, developed for this study, seemed to be critical features for ensuring the successful performance of the participants. First, the participants could discriminate and operate the keys easily. Second, the object detached prior to each travel to an activity remained in the participants’ hands reminding them of the activity to which they were walking. Third, the display of the objects identifying the activities (i.e., on the key areas of the electronic control device) allowed the participants to have an overview of those activities at will and choose the activity engagement sequence with ease (Konrad, Fowler, Walker, Test, & Wood, 2007). The availability of the approval and encouragement/prompting functions may be considered an important asset of the new technology used in this study. Although no direct, formal evidence is available on their specific impact, it is very likely that the approval messages used for Nelly at her arrival at the destinations served as mild social reinforcers motivating her performance and maintaining a level of continuity with the environmental support/approval to which she was used. Probably, she could have become capable of performing without those messages or with few of them. If so, their presence would only have served to make Nelly’s engagement more enjoyable, improving the general atmosphere available for her without costs for staff (Kazdin, 2001; Lancioni et al., 2007; Petry et al., 2005; Zekovic & Renwick, 2003). The encouragement/ prompt messages arranged for Lucille seemed to have an effect on performance at least during the first intervention phase. Again, the data available do not prove that their presence was essential for the final outcome of the program. Yet, it seems safe to state that they helped Lucille learn to be successful and gain full independence with minimal costs for staff (Baldwin, 2003; Lancioni et al., 2008). In conclusion, this study has (a) provided additional evidence as to the importance of orientation technology for helping blind persons with additional disabilities to travel indoor successfully, (b) introduced relevant variations in terms of technology, with a new electronic control device and the availability of approval and encouragement functions, (c) pointed out the potential advantages of the technology package (and related new elements). It should be underlined that the reported technology and its potential advantages need to be viewed in relation to the characteristics of the present participants and not necessarily all participants (i.e., including those with profound intellectual disability). 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