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Eden, S., & Ingber, S. (2014). Virtual environments as a tool for improving sequence ability of deaf and hard of hearing children. American Annals of the Deaf, 159(3), 284–295.

VIRTUAL ENVIRONMENTS AS A TOOL FOR IMPROVING SEQUENCE ABILITY OF DEAF AND HARD OF HEARING CHILDREN

T

SIGAL EDEN AND SARA INGBER

EDEN IS A RESEARCHER AND LECTURER, SCHOOL OF EDUCATION, BAR-ILAN UNIVERSITY, RAMAT GAN, ISRAEL. INGBER IS A RESEARCHER AND LECTURER, SCHOOL OF EDUCATION, TEL-AVIV UNIVERSITY, RAMAT AVIV, ISRAEL.

examined the efficacy of an early intervention program to improve children’s sequential time perception through virtual versus pictorial training in arranging episodes of temporal scripts. The researchers examined 65 deaf and hard of hearing children ages 4–7 years who were divided into two groups: (a) virtual environments technological intervention and (b) pictorial nontechnological intervention. Participants completed pretest and posttest measures. Both groups demonstrated significant improvement in sequential time achievement following intervention. However the improvement was much more significant in the technological group.

H E S T U DY

Keywords: Deaf, hard of hearing, virtual reality, technology, time perception, sequential, language, early intervention

Though time is an essential dimension of human life, deaf and hard of hearing (D/HH) children experience difficulty perceiving this concept (Eden, 2008; Ingber & Eden, 2011; Kaiser-Grodecka & Cieszynska, 1991; Marschark, Lang, & Albertini, 2002). The process of developing the concept of time is gradual, starting in infancy, with complete mastery of all dimensions of time acquired in adolescence (Zakay, 1998). Although researchers have reported that D/HH children have great difficulty with time perception, formal study programs that focus on facilitating their grasp of time are lacking for these children (Eden, 2008; Ingber & Eden, 2011).

In the present study, we conducted an early intervention that aimed to improve sequential time perception by training young D/HH children to ar range episodes of a story’s sequence, using either virtual reality (VR) technology or pictures. Time Perception Among D/HH Children The human experience of change is complex. While one primary element clearly is the experience of a succession of events, distinguishable events are separated by more-or-less lengthy intervals called durations (“Time Perception,” 2014). Thus, sequence and duration are fundamental aspects of what is perceived in the change of time (Fraser, 2000). Time is an abstract concept, based on representative thinking. Respondents who look at a series of

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pictures of an event that develops over time are expected to understand the meaning of each point in time, to fill in the gaps from their own experience, and to construct the sequence of events that develops over time. To do this, respondents must possess an ability for abstraction (Bornens, 1990). Children, acutely aware of the world around them, perceive time as prolonged; every second is played out in real time as their brains soak up information from all directions. While the brains of our children are developing, they are constantly collecting information from the world around them, accumulating knowledge ranging from basic things such as sunrise and sunset to the way the blades of grass move in a slight breeze on a particular hill in their neighborhood (Plummer & Humphrey, 2009). Many studies testify to the difficulties D/HH children have in understanding the abstract (de Feu & Fergusson, 2003; Flatley & Gittinger, 1990; King & Quigley, 1985; Marschark et al., 2002; Passig & Eden, 2000, 2003). Congenital deafness affects different aspects of information processing and time perception (Tirinelli, Brunetti, & Olivetti-Belardinelli, 2009). It seems that hearing deprivation during the early development period might influence the cognitive functioning that connects to perception, management, and the organization of the temporal sequence of stimulus, thoughts, and actions (Bolognini et al., 2011; Conway et al., 2011). Eden (2008) found that D/HH children ages 6–10 years experienced very significant difficulty arranging pictures in temporal order to produce a story. On the pictures series subtest of the Kaufman Assessment Battery for Children (A. Kaufman & N. Kaufman, 1983), a substantial 3.5-year gap emerged between these children’s test scores and their age norms; on the picture arrangement subtest of the third edition of the

Wechsler Intelligence Scale for Children (Wechsler, 1991), the children’s scores were one statistical deviation below the norm. Marschark et al. (2002) noted that even on nonverbal IQ tests designed especially for D/HH children, gaps emerge in favor of hearing children in tasks involving sequence or temporal ordering. There is also some evidence pointing to the possibility of successful performance of such tasks by D/HH children (e.g., Rhys-Jones & Ellis, 2000; Sullivan & Montoya, 1997). Kaiser-Grodecka and Cieszynska (1991) suggested that in order to create an understanding of distance and time relativity, historical events, and causal connections, an abstract category must be created—a sense of historical time—that is not the “here and now.” However, for D/HH children it seems that “time” is connected to the present, which makes it very hard to understand historical time accurately. On the other hand, research by Kelly and Mousley (2001) showed that teachers of D/HH students need to persist in providing natural problem situations so that students become comfortable and confident with the genre of abstract time or mathematical problems. These researchers thus reported that D/HH children’s difficulties in time perception hamper their learning processes and social functioning. Kaiser-Grodecka and Cienszynska found that even older deaf children, ages 12–15 years, displayed severe deficits in using simple time concepts about distant events from the past and the future, in providing full correct answers (rather than scant and schematic ones), in positioning concrete past or future facts on a graphic time scale, and in recalling memories from their own personal past—regardless of whether they were questioned in spoken or sign language. Researchers have suggested numer-

ous explanations for the considerable deficits in time perception found among D/HH children, such as the children’s aural linguistic barrier, limited imagination, difficulties in abstract thinking, Deaf cultural perspective, general problems with sequencing, lack of comprehension of cause and effect (causal thinking), sign language (time order in American Sign Language is not the same as in oral language), and a lack of relevant experiences (Kaiser-Grodecka & Cieszynska, 1991; Marschark et al., 2002; Passig & Eden, 2000; Senior, 1989). Nevertheless, it seems that the aural linguistic deficit is very significant in relation to difficulties in time perception. Language abilities, like time conception, require sequential perception. To utilize language appropriately, children must use internal mental schematic representations, especially words, to build new ideas and thoughts, document them, and communicate them to others (Rom, Segal, & Zur, 2003). Since D/HH children demonstrate significant delays in receptive and expressive vocabulary skills compared to agematched children with normal hearing, prior findings suggest that preschool to primary-age children with hearing loss may be at a serious risk of inadequate acquisition of conceptual knowledge (Harrington, DesJardin, & Shea, 2010). Schafer (2012) examined how D/HH children ages 5 and 6 years with cochlear implants (duration of implant use 2–5 years) perform on tests of their basic concept knowledge. It was found that the children’s performance on the time sequence subtest of the Bracken Basic Concept Scale: Expressive (Bracken, 2006), including temporal ordering of events, was delayed relative to that of hearing children. Senior (1989) attributed children’s difficulties in developing time perception to their cultural perspective and to their hearing and linguistic

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VIRTUAL ENVIRONMENTS AND SEQUENCING developmental problems. She suggested that being D/HH may affect one or more of these factors and hence affect temporal orientation. She emphasized that linguistic deficiency is an important but not exclusive factor shaping the comprehension of time among people who are D/HH. Recently, we conducted a 3-month intervention to enhance the sequential time perception and storytelling ability of young D/HH children (Ingber & Eden, 2011). The children were trained to arrange pictorial episodes of temporal scripts and tell the stories they created. Participants were divided into two groups based on whether their spoken-language gap was more or less than 1 year compared to age norms. Measures demonstrated significant improvement in sequential time achievement postintervention. Also, previous research (Eden, 2008) had examined whether D/HH children perceive a temporal sequence differently at kindergarten age and at elementary school age under different representational modes: three-dimensional virtual reality (3D VR), pictorial, textual, spoken, and signed representation. The findings demonstrated that the 3D VR representation and the signed representation enabled the best perception of sequential time. The poorest results were for the textual representation. The present study, which has its basis in the findings of Eden (2008), expands the pictorial intervention developed in our 2011 study, and adds a unique technological intervention that used VR. Virtual Reality and Children With Special Needs The intervention program for the present study used VR, a computer-simulated environment that can simulate places in the real world as well as in imaginary worlds. Computer graphics are used to create a kind of extension

of existing reality in which a person can hear, see, touch, and communicate with objects and figures. This mode enables the user to take an active part in the environment, rather than be a passive observer. VR has application in different areas—for example, gaming, the military, the automotive industry, architecture, medicine, and education. Most current VR environments are primarily visual experiences, usually displayed on a computer screen, but some simulations include additional sensory information, such as sound and tactile information (Burdea & Coiffet, 2003; Cliburn, 2004; Santos et al., 2009). The innovative concept of this platform lies in the use of VR technology for the development of a working display environment that also provides navigation, immersion, and interaction capabilities for all collaborative users in real time. In this way, users are not passive, but, rather, use some or all of their senses in the extended environment so that the actual use of the technology contributes to the learning. VR does not limit the presentation of information or users’ movements. Consequently, abstract concepts can be presented in a creative way by making them more concrete, and by presenting a perspective on processes that the real world cannot provide (Eden & Passig, 2007; Ellis, 2000; Passig & Eden, 2003). Various studies have investigated VR and its impact on populations with conditions such as physical disabilities, sensory deficits, learning disabilities, and attention deficits (Bowerly, 2002; Harris & Reid, 2005; Passig & Eden, 2000; Rizzo, Strickland, & Bouchard, 2004; Standen, Brown, & Cromby, 2001). These studies were designed to see whether it is possible to improve independence and various functioning skills, and to determine whether it is possible to increase individuals’ selfconfidence (Standen & Brown, 2005;

Tam, Man, Chan, Sze, & Wong, 2005; Weiss, Bialik, & Kizoni, 2003). For example, Eden and Bezer (2011) examined the effect of an intervention program employing 3D VR, which focused on the perception of sequential time, on the mediation level and behavioral aspects of 87 children with mild to moderate intellectual disability. The intervention program included three mediation levels, full, partial, and no mediation, in individually based direct instruction. The emotional, cognitive, and behavioral dimensions of the participants’ behaviors were also examined. The participants were divided into two experimental groups, one of which experienced sequential time scenarios in 3D VR, while the other experienced the same scenarios via a series of 2D pictorial episodes. The findings indicate that the 3D VR group required less mediation than the 2D pictorial group. In the behavioral dimension, a distinct advantage was found for the participants in the 3D VR group. They were more focused on the assignment, more immersed physically in the virtual worlds, and were less frantic and stressed. In previous research (Eden, 2008; Eden & Passig, 2007), D/HH children were examined in order to understand whether they would perceive a time sequence differently under different representational modes. Eden and Passig compared the effect of 3D VR representation on sequential time perception among D/HH and typically hearing children ages 4–10 years with pictorial, textual, spoken, and signed representation. The findings demonstrate that the VR representation (for both groups) and the signed representation (for D/HH children) enabled the best perception of sequential time. The poorest results were for the textual representation. In the present study we extended these findings, hypothesizing that an

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early intervention program, practicing sequential time through training in arranging and verbally describing pictorial versus VR scenarios, would improve those abilities for D/HH children. As mentioned above, in a previous study we had developed a pictorial intervention program that showed the significant improvement made by D/HH children in sequential time achievement following an intervention that trained them to arrange pictorial episodes of temporal scripts (Ingber & Eden, 2011). In the present study, a VR program was added so that we could see if the technology advanced children’s performance. For this study, sequential time was defined in ranges of days, weeks, months, and years, and was studied with regard to their order in sequence (Piaget, 1923/2002). Method

Participants The participants in the present study were 65 Israeli kindergarten children (25 boys, 40 girls) ages 4 years to 6 years 6 months (M = 63.91; SD =10.05) whose hearing loss was identified early in life and who had no additional disabilities.1 At the time of the study, the participants comprised two groups: 42 children attending inclusive kindergartens (individually integrated) and 23 in special coenrollment kindergarten (group integrated) settings. The children who were individually integrated into regular kindergartens in their local neighborhoods represented the approximately 60% of young D/HH Israeli children in inclusive settings (Most, Ingber, & HeledAriam, 2012). To meet the criteria for inclusion, children’s language level had to approximate that of their hearing peers (i.e., could not lag more than 1 year behind). These children were receiving hearing, speech, and language therapy at two locations: the kindergarten classroom and the clos-

est MICHA center. (MICHA is a multidisciplinary center for children with hearing loss.) All children in the inclusive kindergarten usually communicate solely through spoken language. The participants who were integrated as a group (the coenrollment group) represented the approximately 50% of young D/HH Israeli children in coenrollment settings. Children selected for coenrollment evidence significant language delays and require more intensive education therapy than those eligible for individual inclusion. In these kindergartens, D/HH children are primarily taught in small, segregated classes, but do participate in general education activities with hearing children their own age. The coenrollment model potentially may solve some of the difficulties inherent in the individual inclusion model because the special education teacher works as a full-time member of the team, not as a visitor. The special education teacher can integrate intensive and specialized instruction into the classroom curriculum. In addition to the classroom teacher’s speech instruction, an itinerant speech therapist provides speech therapy services as needed (Aram, Ingber, & Konkol, 2010). Coincident with the different criteria for the inclusive and coenrollment settings, the children in the two settings revealed a significantly different pattern of spoken-language levels. The language level of each child enrolled in the MICHA intervention center is tested annually to assess progress and to address specific needs while the child’s individualized education program is planned. The evaluation is performed annually by a speech pathologist and includes several tests, such as the Guralnik (1982) language screening test; the Preschool Language Scale (3rd ed.), which assesses a child’s receptive and expressive language

(Zimmerman, Steiner, & Pond, 1992); and the Reynell Developmental Language Scales (Reynell & Huntley, 1985), which are used to assess the child’s language comprehension ability. In our study, according to language and communication assessments that were performed for all the children annually in their educational settings, the vast majority of the children in the inclusive group (94%) revealed spoken-language delays of less than 1 year compared to the norms for their age group, whereas 88% of the children in the coenrollment group revealed spoken-language delays greater than 1 year compared to their age norms. Table 1 presents the participants’ demographic characteristics by intervention group. Etiology and mother’s hearing status were not reported for two children, and father’s hearing status was not reported for five children. As Table 1 shows, per definition, the two intervention groups differed significantly between the inclusive and coenrollment settings: VR group = inclusive 80.6%, coenrollment 19.4%; picture group = inclusive 50.0%, coenrollment 50.0%. The distribution of study participants according to the various demographic characteristics (in Table 1) coincides with that shown in data already available on the D/HH population in Israel (Eden, 2008). Interestingly, we found that 100% of the children in our study who had D/HH parents were reported by their teachers as having a genetic etiology for their deafness. Moreover, most of the D/HH children with genetic etiology (77%) started early intervention before 1 year of age.

Intervention Design Training Materials: Pictorial Scenarios Three 2D illustrated temporally logical animated pictorial scenarios were

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VIRTUAL ENVIRONMENTS AND SEQUENCING Table 1

Participants’ Demographic Characteristics, by Intervention Group Intervention group VR intervention

Pictorial intervention

Characteristic

Subgroup

N

%

N

%

X2

df

Sex

Boys Girls Inclusive Coenrollment 0–1 1–3 4–5 Yes No Unknown Genetic Illness and birth problems Moderate Severe Profound Hearing aid(s) Cochlear implant(s) Both Yes No Oral Signed Hebrew 1 year Hearing Hearing loss Hearing Hearing loss

11 20 25 6 18 5 8 14 17 13 14 2 14 6 11 22 5 4 2 29 24 7 15 16 20 10 22 8

35.5 64.5 80.6 19.4 58.1 16.1 25.8 45.2 54.8 44.8 48.3 6.9 45.2 19.4 35.5 71.0 16.1 12.9 6.5 93.5 77.4 22.6 48.4 51.6 66.7 33.3 73.3 26.7

14 20 17 17 20 9 5 8 26 17 12 5 15 6 13 23 6 5 8 26 30 4 18 16 27 6 24 6

41.2 58.8 50.0 50.0 58.8 26.5 14.7 23.5 76.5 50.0 35.3 14.7 44.1 17.6 38.2 67.6 17.6 14.7 23.5 76.6 88.2 11.8 52.9 47.1 81.8 18.2 80.0 20.0

0.22

1

6.66 ** 1.81

1

3.39

1

1.59

2

2.37

2

0.09

2

3.63

1

1.35

1

0.14

1

1.90

1

0.37

1

Setting Age at onset of treatment (years)

Siblings with hearing loss Etiology

Degree of hearing loss

Amplification

FM Communication Language age gap Mother’s hearing status Father’s hearing status

2

Notes. VR = virtual reality. The differences between the groups was calculated with the chi-square test for independence. ** p < .01.

developed by Eden and Passig (2007) to train study participants in sequential time perception ability. Each scenario consists of four or five animated color pictures that form a story with a time sequence. The three scenarios are taken from the daily life of a child who is baking a cake, planting a tree, and making a chocolate milk drink. Eden and Passig gave the pictures and the scenarios expert validation and found them suitable. The pictures were presented randomly, and the child had to arrange them according

to the sequence of their occurrence. For example, a script for the planting of an orange tree was divided into four different episodes: The first episode depicted a small child digging a hole to plant a small seedling; the second depicted a large seedling being watered by a young boy; the third depicted a teen watering a tree; the final episode showed a grown man standing under a fully grown orange tree. This script had a temporal order in which one cannot water the plant before it is planted.

Training Materials: VR Scenarios The same 2D animated scenarios were generated as 3D VR worlds. The participants used a mouse to navigate, manipulate, and interact with them. Each of the episodes had its own opening screen represented by a picture. Four small, separate pictures in random order appeared in a column on the right side of the screen, representing different episodes of the scenario. When any picture was pressed, the participant was brought into a specific

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VR episode in which she could move around in the environment, using the mouse to manipulate the objects and interact with them. For example, in the “baking a cake” script, the participant could press the eggs so that they cracked into the bowl. The experience included visual and auditory 3D stimuli, which generated the sense of immersion in the episode. After experiencing the VR world, the participants entered a multimedia program designed to arrange the episodes in the correct sequence for the scenario. The main screen was made up of four or five squares. A number appeared on each episode, as did small circles for the visual identification of the number. Four pictures representing the episodes belonging to the scenario appeared on the lower part of the screen. The participants were asked to drag the pictures using a mouse and arrange them in the appropriate place on the squares according to the logical time sequence they had worked out. After a participant finished, he would press a button that allowed him to generate and watch a video clip (consisting of the four episodes) reflecting the time sequence he had created. Individual participants also received feedback from the multimedia program informing them if their time sequences were correct or not.

Clinicians and Communication Mode The 15 clinicians who conducted the intervention for the present study all held BA degrees in communication disorders, were fluent in Hebrew and Israeli Sign Language, and had at least 2 years of experience working with children who were D/HH. Each clinician worked with a group of children through the year and was familiar with the specific child who participated in the study. The clinician matched the mode of communication to every child

according to the criterion of that child’s proficiency (ability to understand and use) in spoken language or sign language. To ensure fidelity, all clinicians were trained individually and in a group for the intervention by the researchers before and during the children’s intervention program, and they received structural guidance and an instruction booklet including information regarding time sequence, explanations about the intervention, instructions regarding the intervention structure, and training in how to perform standardized mediation (see below).

Intervention The intervention was conducted over a 3-month period in a quiet room in the kindergarten for the children in the coenrollment setting and at the MICHA center for the children in the individual setting, in individual weekly meetings of about 20 minutes’ duration every week. The first session began with a demonstration by the clinician, and all of the following sessions had the same six-step structure. Step 1. In the pictorial scenarios, the clinician first placed the four pictures of the first scenario—cake baking—on the table, one at a time, in front of the child in random incorrect order, from the child’s right to left (in accordance with the direction of the Hebrew alphabet). She then asked the child to rearrange the pictures in the correct sequence. After the child arranged the pictures, the clinician asked the child to tell the story depicted by that sequence “in your own words.” In the VR scenarios, the procedure was identical, but the clinician used a computer to show the different episodes to the child. In each scenario, the child could interact using the mouse. After the child finished experimenting with the scenarios, she arranged the pictures using the multimedia program de-

signed to arrange the episodes in the correct sequence for the scenario. Step 2. If the child did not arrange the pictures correctly, and therefore told an incorrect story, the clinician asked the child to rearrange them. If the child fidgeted or refused to rearrange the pictures, the clinician thanked the child and ended the intervention session. If in two consecutive weekly sessions the child did not successfully arrange the pictures in the correct order, the clinician provided standardized mediation to help the child’s sequencing—for example, “Try to think again—what happens after that?” “Is this picture in the right place?” “What do you think will happen after that?” Step 3. Only if the child arranged the pictures correctly did the clinician administer the next scenario—which was about hot chocolate. In this second story, the child was again asked to arrange the sequence of four pictures independently, without an initial demonstration, and to describe the story “in your own words.” In the VR intervention, the child interacted with each scenario before arranging the picture according to the time sequence. Step 4. Repeat Step 2. Step 5. Only if the child arranged the hot chocolate pictures correctly did the clinician administer the next story—on planting a tree. In this third story, the child was again asked to arrange the sequence of four pictures independently, without an initial demonstration, and to describe the story “in your own words.” Step 6. Repeat Step 2.

Sequential Time Perception Assessment: Picture Series Subtest All participants were assessed at pretest and posttest on the picture series measure, to examine improvement after intervention in sequential time perception.

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VIRTUAL ENVIRONMENTS AND SEQUENCING We used the pictures series subtest of the second edition of the Kaufman Assessment Battery for Children, or KABC-II (A. Kaufman & N. Kaufman, 1996), to measure temporal sequence perception. Children were asked to organize, without mediation, 17 series of illogically sequenced pictures (with 4–6 pictures per series) to fit the correct time sequence of events depicted in those pictures. The children were asked only to organize the pictures by sequence, and no language was required. For each picture, they got a score of 1 for correct placement and 0 for incorrect placement. Raw scores were calculated as the number of correct answers, and were converted to standard scores with a special key. The instrument’s Cronbach alpha was .76.

Procedure After approval was obtained from the Tel Aviv University ethical committee and the head scientist at the Israeli Ministry of Education, as well as the consent of the parents, all the D/HH children ages 4–7 years who attended educational settings in the Tel Aviv and central districts MICHA centers participated in the study. The researchers divided the participants into two groups according to the language delays reported in their records: children with a spoken-language gap less than 1 year below age norms, and children whose language gap was greater than 1 year. Then, each group was divided randomly into two groups—pictorial intervention and VR intervention. A trained research assistant administrated the Kaufman test to each child individually at the child’s kindergarten for about 20 min. At the end of the intervention, after 3 months, the research assistant administrated the same test again. After the intervention, parents received feedback on their children’s performance.

Table 2

Means and Standard Deviations of Time Sequence, by Research Groups and Pretest/Posttest Virtual reality group (n = 31)

Pretest Posttest

Pictorial group (n= 34)

Total

M

SD

M

SD

M

SD

1.06 6.13

1.50 3.27

2.18 4.71

2.12 3.35

1.65 5.38

1.92 3.37

Results In order to examine participants’ progress in sequential time perception resulting from the intervention, we conducted a two-way mixed ANOVA with the intervention groups as the between-subjects factor and the time (pretest vs. posttest) as the within-subject factor. Table 2 shows the means and standard deviations of the two groups, and the results of the pre- and posttest of sequence time. Significant improvement was found at the posttest compared to the pretest when averaged across the two intervention groups, F(1, 63) = 126.33, p < .001, partial eta2 = .67. Also, a significant interaction effect was found between the time of the measure and the intervention, F(1, 63) = 14.08, p < .001, partial eta2 = .18. A simple effect

analysis found that at the pretest the pictorial group did significantly better than the VR group, t(63) = 2.44, p < .02, Cohen’s d = 0.61. At the posttest measure the VR group showed a marginally significant higher performance than the pictorial group, t(63) = 1.73, p < .08, Cohen’s d = 0.44 (see Figure 1). To examine the influence of the measures that predicted the improvement in performance in participants’ sequential time perception, we devised an index to show the improvement (e.g., instead of showing the mean result of 2 at pretest and 5 at posttest, we showed the index of improvement, which was 3). Using two-way between-subjects ANOVA, we also examined whether the difference in the two intervention

Figure 1

Participants’ Sequential Time Perception at Pretest and Posttest

Note. VR = virtual reality.

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groups in the improvement in performance differed by demographic characteristics. There was no significance difference on the performance improvement between participants with a language age gap of less than or more than 1 year, F(1, 61) = 0.72, ns, partial eta2 = .01, and no interaction between the language age gap and the intervention was found, F(1, 61) = 0.07, ns, partial eta2 = 0. A significant difference was found among the three etiology levels on the performance improvement, F (2, 57) = 3.56, p < .05, partial eta2 = .11, where the performance of the D/HH participants with genetic causes of hearing loss (M = 4.92, SD = 3.05) was higher than that of D/HH participants with unknown causes (M = 2.90, SD = 2.73), and the performance of those whose hearing loss was caused by other reasons (M = 2.14, SD = 2.19). No interaction was found between the VR and pictorial intervention groups and the reasons for the hearing loss, F (2, 57) = 0.35, ns, partial eta2 = .01. In order to examine the improvement in performance in participants’ sequential time perception according to the intervention groups and the type of the educational setting, we conducted a two-way ANOVA. There was no significance difference on the performance improvement between participants’ educational setting, F(1, 61) = 0.97, ns, partial eta2 = .02, and no interaction between educational setting and the intervention was found, F(1, 61) = 0.06, ns, partial eta2 = 0. To examine the improvement in performance in participants’ sequential time perception according to the intervention groups and the age at onset of treatment, a two-way ANOVA was conducted. No significant difference was found between the age at onset of treatment and the improvement in performance, F(1, 61) = 1.38, ns, partial eta2 = .02. A significance

interaction effect was found between the intervention groups and the age at onset of treatment, F(1, 61) = 6.90, p < .05, partial eta2 = .10. The origin of the interaction was in the fact that in the VR group there was no difference between respondents up to 1 year of age at onset of treatment (M = 4.67, SD = 2.95) and those more than 1 year of age at onset of treatment (M = 5.62, SD = 3.12). On the other hand, in the pictorial group the improvement in performance was significantly higher in the group up to 1 year of age at onset of treatment (M = 3.55, SD = 2.35) compared to those more than 1 year old at onset (M = 1.07, SD = 1.73). We also examined the influence of the severity of the hearing loss on the improvement in performance. No significant difference was found between children with different hearing loss severity, F(1, 59) = 0.01, ns, partial eta2 = 0, nor any interaction, F(1, 59) = 0.63, ns, partial eta2 = .02). Another variable that we examined was the type of amplification. No significant difference was found between using hearing aids and using a cochlear implant in regard to the improvement in time sequence performance, F(1,61) = 0.35, ns, partial eta2 = .01, and no interaction, F(1, 61) = 0.65, ns, partial eta2 = .01. Regarding variables related to parental characteristics, we examined the connection between the parents’ hearing status and the participants’ improvement in time sequence after the intervention. A significant difference between the father’s hearing status and the improvement in performance was found, with children of D/HH fathers showing a higher degree of improvement than children of hearing fathers, F(1, 56) = 5.83, p < .05, partial eta2 = .09; no interaction was found, F(1, 56) = 0.02, ns, partial eta2 = 0. No significant difference was

found between the mother’s hearing status and the improvement in performance, F(1, 59) = 1.81, ns, partial eta2 = .03, and no interaction, F(1, 59) = .82, ns, partial eta2 = .01. Discussion D/HH children can experience difficulties in time perception (Eden, 2008; Ingber & Eden, 2011; Kaiser-Grodecka & Cieszynska, 1991; Marschark et al., 2002). Yet we found that an early intervention program, using colored pictures, can improve this ability (Ingber & Eden, 2011). The findings of the present study demonstrate clear improvement in children’s performance after the intervention program (in the pictorial group as well as the VR group) compared to pretest scores. These results are compatible with prior findings, that D/HH children need an early intervention program that enhances their abilities to acquire language, speech, and cognitive perception (Moeller, 2000).

Sequential Time Perception Through Virtual Versus Pictorial Training In the present study, a technological intervention program was developed that aimed to enhance the perception of sequential time among D/HH children. It was administered as a VR program to one intervention group and as a pictorial program to a second intervention group. The results of the study showed that both intervention groups improved their time sequence ability, yet the ability of the children in the VR group improved practically and significantly (six times better) than that of the pictorial group. Moreover, the study demonstrated that what affects a child’s improvement in sequential time perception is not the language level of the child, but the technology that is used to mediate the child’s concept of time. That is, no matter whether

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VIRTUAL ENVIRONMENTS AND SEQUENCING a child has a small or large gap between his language level and what is expected from a child of his age, VR technology works to improve the child’s perception of sequential time. The research literature indicates that an appropriate intervention program with VR technology plays an essential role in improving various abilities of children with special needs (Eden, 2008; Eden & Bezer, 2011; Standen & Brown, 2005; Tam et al., 2005; Weiss et al., 2003). A possible explanation for the positive results derives from the capacity of VR to concretize the abstract. Studies reconfirm that immersion in VR improves the ability to understand abstract concepts, by making them more concrete and probably easier to perceive (Eden, 2008; Eden & Passig, 2007). Abstract material is difficult to teach in any other manner, and VR seems to be a promising educational medium (Salzman, Dede, Loftin, & Chen, 1999). One of the critical features of 3D VR environments is their capacity to visually depict spatial representations of abstract concepts so that users can interact with them (Merchant et al., 2013). Our research suggests that such immersive, multisensory experiences enhance students’ abilities to conceptualize and integrate complex, abstract ideas such as time sequence. Another explanation touches on the interactivity of VR, and on its ability to cause a D/HH child to be especially active. There is a high level of similarity to life in VR, enabling the participant to be part of the virtual world. It is a kind of expansion of the existing reality, in which a person can hear, see, touch, and communicate with objects and images. This method enables the child to become an active part of the environment, not solely a passive observer, as in the pictorial intervention (Barab, Hay, Barnett, & Squire, 2001; Harper, Hedberg, & Wright,

2000). Active learning has long been considered a proven method for increasing attention, motivation, and retention of concepts, especially among deaf children (Parton, Hancock, & Dawson, 2010). The acknowledged efficacy of active learning may suggest that children need a more active mode of representation and expression in order to attain a higher level of abstraction. A different explanation of the results of the present study is that VR is a fun, motivating, and novel tool. It seems that even though all the children participated willingly in both intervention programs, it was clear that the children in the VR group were more motivated to use the technology. It is possible that interventions such as this can motivate young children because of their novelty. Children using VR have reported high levels of motivation in other studies (Kirshner, Weiss, & Tirosh, 2011; Parsons, Rizzo, Rogers, & York, 2009).

Variables Related to Child Functioning Regarding the child demographic variables, our study indicated that what affects a child’s improvement in sequential time perception is not the language level of the child, but the technology that was used to mediate the child’s perception of time. That is, no matter whether a child has a small or large gap between her language level and what is expected from a child of her age, VR technology works to improve the child’s perception of sequential time. An explanation for this finding can be derived from the concept that an appropriate intervention program with VR technology plays an essential role in improving various abilities of the child with special needs and has a better impact on that child’s progress (Eden, 2008; Eden & Bezer, 2011; Standen & Brown, 2005).

We also found that the performance of the D/HH children with a genetic cause of hearing loss was better than that of D/HH children with an unknown etiology, or any other cause of hearing loss. Genetic factors, thought to cause more than 50% of congenital hearing loss in children (National Institute on Deafness and Other Communication Disorders, 2005), are identified in early infancy, and therefore these children begin habilitation very young. All the children in our study who had deaf parents were identified with a genetic etiology, and 77% of the children with a genetic etiology started early intervention before 1 year of age. Together, these findings suggest that most D/HH children will improve their sequential time performance after being involved in an early intervention program and, moreover, after exposure to mediation targeting cognitive issues (Eisenberg et al., 2007; Moeller, 2000). A different explanation of these results is that children with a genetic etiology are also more likely to have Deaf parents. As such, they may be more likely to be exposed to language (signed language) and natural incidental learning opportunities in their homes. Such children may have a stronger foundation to support the later learning of academic concepts (Mitchell & Karchmer, 2004). Another explanation may be reasonably expected on the basis of the multiple different etiologies of deafness. Deafness from genetic causes has no known comorbidity. Individuals walk at a normal age and appear to have normal function despite the heterogeneity of genetic deafness (Green et al., 2002). Perhaps be this is the reason they perform better then children with unknown causes. Interestingly, the present study did not indicate differences in time sequencing regarding amplification devices. Children with cochlear implant(s)

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showed the same improvements as their peers with hearing aid(s). Perhaps the young age of the children in the study influenced the results. Despite their young implantation age, the children with one or more cochlear implants in the study did not have much experience with this technology. We recommend further investigation of this issue with older children. Regarding parental variables, we examined the connection between the parents’ hearing status and the improvement of the participants in time sequencing after the intervention. It was found that children of D/HH fathers showed greater improvement than children of hearing fathers. No connection was found to the mother’s hearing status. Mitchell and Karchmer (2004) demonstrated that knowing the gender of D/HH parents is important, and that it is far more common for data on the father to be unavailable than data on the mother. Otherwise, gender identification did not reveal any remarkable patterns. One possible reason for our findings is that the sample for the present study was not big, and most of the fathers were hearing. We recommend further investigation of this issue.

Implications of the Study With acknowledgment of the limitations of the experimental design, subject sample, and analysis procedure we employed, the following conclusions are presented. Taken together, the findings of this exploratory study demonstrate that despite the great difficulty in time perception reported for D/HH children (Bylholt, 1997; Eden, 2008), a specifically developed early intervention program can promote competency in this area, especially a program that includes the use of VR technology. The outcomes of the study suggest that misperception of time sequences among

D/HH children may be responsive to appropriate intervention. However, current early intervention programs for D/HH children in Israel lack formal curricula targeting the topic of time. The intervention we have described in the present article can serve as a preliminary guide for curriculum development to enhance time sequencing. Several limitations in the design and variable selections should be discussed. First, to further understand D/HH children’s ability to perceive time sequences, future intervention programs should include other representation modes, not just pictorial images and VR, such as sign language and other computerized stimuli. Second, the small sample size did not allow for exploration of the multiple personal and interpersonal factors that may contribute to children’s performance on time sequencing or storytelling. In this context, future studies should focus on risk factors such as the children’s degree of hearing loss, comorbidity, cognitive performance, or rank in the family. Although generalization was beyond the purview of the study, we do not know from the findings of this study whether the noted improvements in performance will generalize to the real world. Finally, because this study was conducted among Israeli children, who may be affected by sociocultural factors, we recommend cross-cultural validation to generalize its findings. Note 1. The discussed participants are identical to those analyzed by Ingber and Eden (2011) in previous research. References Aram, D., Ingber, S., & Konkol, S. (2010). Promoting alphabetic skills of young children with hearing loss in co-enrollment versus individual inclusion. L1—Educational Studies in Language and Literature, 10(1), 139–165. Retrieved from MICHA website:

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