What Are the Benefits of Using Baby Sign Language for Both Parents and Child

J Appl Behav Anal. 2007 Bound; 40(1): fifteen–23.

Enhancing Early Communication through Infant Sign Training

Louis Hagopian, Activity Editor

Received 2006 Feb 24; Accepted 2006 Jun 28.

Abstruse

Existing research suggests that there may exist benefits to teaching signing to hearing infants who have not nonetheless adult song advice. In the current written report, each of four infants ranging in historic period from 6 to ten months was taught a simple sign using delayed prompting and reinforcement. In improver, Experiment ane showed that 2 children independently signed in a variety of novel stimulus conditions (e.1000., in a classroom, with father) after participating in sign training under controlled experimental weather. In Experiment 2, crying and whining were replaced with signing when sign training was implemented in combination with extinction.

Keywords: communication grooming, extinction, infants, modeling, physical prompting, reinforcement, sign language, delay

Sign language systems have been used successfully with individuals who accept difficulty learning to communicate through song language. In add-on to individuals with hearing impairments, individuals with developmental disabilities such as autism and mental retardation have learned to communicate through signs (Bryen & Joyce, 1986). Signing may be a good alternative to vocal communication for individuals who take poor oral motor control merely acceptable transmission control. For these individuals, sign language may exist easier to teach than oral language considering signing can be physically prompted past a caregiver (i.e., a child's hands tin can exist molded to grade a sign; Tabor, 1988).

These advantages have led some researchers and clinicians to recommend that signing as well be taught to typically developing children during their first 2 years of life (Acredolo & Goodwyn, 1996; Garcia, 1999). This recommendation is supported past studies showing that infants exposed to sign linguistic communication acquired first signs at an earlier age than typical first spoken words. Bonvillian, Orlansky, and Novack (1983) studied xi hearing children of deaf parents and reported that children produced their first recognizable sign at a mean age of just 8.five months, with the earliest get-go sign at 5.5 months. Similarly, Goodwyn and Acredolo (1993) found that, when hearing parents were trained to encourage the utilise of symbolic gestures (eastward.thou., palms up for "Where is it?"), their hearing infants began to utilise gestures a mean of 0.69 months before their first song words.

A business concern associated with the early utilise of sign language is the potential for a delay in the onset of vocal language; notwithstanding, results of a study by Goodwyn, Acredolo, and Brown (2000) suggest that sign training might facilitate rather than hinder the development of song language. In this written report, hearing infants whose parents encouraged symbolic gestures outperformed children whose parents encouraged vocal linguistic communication on follow-up tests of receptive and expressive song language.

These results provide preliminary bear witness suggesting that there may be benefits to teaching sign linguistic communication to young children who have not yet developed song language. Yet, these studies provide picayune guidance regarding effective sign preparation procedures because parents and children were non straight observed during sign training. By contrast, Thompson, McKerchar, and Dancho (2004) described a set of procedures that was effective in producing signing in 3 infants (6 to 13 months). Training consisted primarily of delayed physical prompting and reinforcement for prompted and independent signs, and each child acquired the target sign subsequently less than 4 hr of training. Yet, a limitation of this written report was that signing was taught and measured only nether controlled experimental atmospheric condition. Therefore, it is unclear whether sign preparation resulted in functional advice for these children. Experiment i of the current written report was designed to extend Thompson et al. by evaluating the extent to which signs trained under experimental conditions would occur independently under more natural conditions.

Although infants begin communicating with their caregivers at an early age through facial expressions, gazes (e.grand., Yale, Messinger, Cobo-Lewis, & Delgado, 2003), and vocalizations such as cooing, crying is the primary fashion of advice for infants. Crying is constructive at evoking a diverseness of caregiving responses, only a limitation of this form of communication is that caregivers must frequently rely on contextual cues to decide the advisable response (Costello, 1976; Petrovich-Bartell, Cowan, & Morse, 1982). For example, when an infant cries immediately post-obit a meal, parents may exist less likely to feed the child and more than likely to put the child to sleep. However, in some cases, contextual cues may be absent or ineffective at occasioning the appropriate form of caregiving, resulting in persistent crying. By dissimilarity, one reward of sign language is that signs, like vocal responses, have the potential to specify their reinforcers; thus, signing may occasion more effective caregiving. In improver, despite the fact that crying is a developmentally normal class of communication for infants, data on parental behavioral and physiological responses suggest that crying is an aversive issue (Brewster, Nelson, McCane, Lucas, & Milner, 1998; Donovan, 1981; Frodi & Lamb, 1980); thus, for caregivers, signing may be a more than preferred form of communication for their infants. Therefore, in Experiment 2, we attempted to supervene upon infant crying and whining with signing.

Experiment 1

The purpose of Experiment ane was to evaluate the furnishings of delayed model and physical prompts and reinforcement on the acquisition of signs in 2 infants. These procedures were similar to those described by Thompson et al. (2004); however, a model prompt was used in addition to physical prompting. Post-obit acquisition, nosotros sought to decide whether signs acquired under controlled experimental conditions would occur in more natural settings, in the presence of multiple listeners, and nether the command of multiple reinforcers.

Method

Participants and Setting

Participants were Heather, a ten-calendar month-former infant with Down syndrome, and Betty, a 6-month-onetime babe of typical development. Both children attended a full-24-hour interval baby and toddler programme, and neither child communicated consistently through song or signed advice. Sessions were constructed to teach children to request items or activities that parents or teachers had identified every bit preferred. Heather was taught to request an array of toys (e.chiliad., balls, musical toys) and experimenter attention, and Betty was taught to request a bite of baby nutrient and brief experimenter attending. Betty's sessions were conducted during her regularly scheduled mealtime, and the classroom carte du jour adamant the foods (eastward.g., rice cereal, pureed fruit or vegetable) presented in session. Initially, experimental sessions were conducted in a small therapy room equipped with a ane-fashion observation window. After, the intervention was extended to habitation and school settings. Sessions were 5 min in length and were conducted one to three times per 24-hour interval, 5 days per calendar week. Sessions were scheduled so they did not interfere with children's daily routines (e.chiliad., naps).

Response Measurement and Interobserver Agreement

Observers recorded the frequency of independent and prompted signs. The target sign for Heather was a modified form of the American sign linguistic communication (ASL) sign "please," divers as the palm of one manus touching the chest while moving back and forth. The target sign for Betty was a modified form of the ASL sign "more than," scored when both easily moved toward her midline and touched together. For both participants, prompted signs were those that were physically prompted and those that occurred within five s of a model prompt, and contained signs were those that occurred prior to an experimenter prompt.

Interobserver agreement was assessed past having a second observer simultaneously but independently record data during a minimum of 33% of sessions for each participant. Agreement percentages were calculated by partitioning the session into 10-s intervals and comparing observers' records on an interval-past-interval basis. For frequency and duration measures, the smaller number of responses (or duration of the response) in each interval was divided by the larger number; these fractions were and so averaged across intervals and multiplied by 100% to obtain a percentage understanding score. Mean understanding beyond participants was 95% (range, 84% to 100%) for independent signing and 98% (range, 82% to 100%) for prompted signing.

Procedure

Initial Baseline

During baseline sessions, the reinforcer (toys or food, paired with experimenter attention) was presented according to a time-based schedule, independent of the participant's behavior. For Heather, the experimenter presented the toys and attention every one min for thirty s. For Betty, the experimenter presented one bite of baby food at the showtime of the sessions and 10 southward after Betty swallowed the previous bite of nutrient. Schedules of reinforcer delivery were established arbitrarily during the initial baseline phase.

Sign Training

When sign grooming was initiated, a model prompt was delivered immediately at the beginning of each session and after the termination of each subsequent reinforcer commitment. If signing did not occur inside v due south of the model prompt, the participant was physically prompted to perform the target sign. In addition, if the participant performed an approximation to the sign (e.thou., if Betty brought her hands toward her midline but did non bear upon them together), a physical prompt to perform the sign accurately was provided (e.chiliad., the therapist gently guided her hands together). The designated reinforcer was delivered following all prompted and independent signs. The filibuster to the model prompt was gradually increased from 0 s to 80 due south, or until high levels of independent signing occurred for several sessions. A physical prompt (if necessary) was delivered five s after the model prompt throughout all training weather. With some exceptions (noted below), participants were exposed to 5 consecutive sessions at each level of delay (e.thou., 0 s, five s, 10 s) during the initial sign-training phase and 3 (Betty) or five (Heather) sequent sessions at each level during the subsequent sign-training phase.

Reversal to Baseline

Procedures were like to those in the initial baseline stage, except that schedules of reinforcer delivery were designed to match the rate of reinforcer commitment during sign preparation. The schedule of reinforcer delivery was based on the mean interresponse time from the last 5 sessions of the sign-preparation status. Heather received toys and attention 60 s later their removal, and Betty received a seize with teeth of food five south after consuming the previous bite.

Sign-training Extension

To evaluate whether contained signing taught under experimental weather condition would occur under more natural conditions, sign-training sessions were conducted with additional experimenters, in additional settings, and with other reinforcers. Otherwise, procedures were similar to those used in the sign preparation atmospheric condition. For Heather, sessions were conducted with different experimenters (a novel researcher and an early childhood educator) and in unlike settings (classroom and indoor playground), and signing "delight" resulted in access to different reinforcers (Goldfish® crackers and a riding toy). For Betty, sessions were conducted with boosted experimenters (a classroom instructor and her male parent) and in unlike settings (classroom, male parent'south office, and home).

Experimental Design

The effects of sign training were evaluated by comparison baseline and sign-training in a reversal blueprint.

Results

Heather's data are depicted in Effigy 1. She did non sign during the initial baseline stage. Sign grooming began at the 0-s delay to the model prompt, and the delay was gradually increased to 35 south, with no independent responses. Nosotros chose to keep the delay constant at 35 southward to expose Heather to frequent prompting. Beginning at Session 57, we observed a gradual increase in independent signing. Loftier and stable levels of independent signing were achieved, with no prompts, at the 40-s delay. An immediate subtract in contained signing was observed during the return to baseline, and Heather displayed high levels of independent signing when sign training was reinitiated at the 40-s delay to the model prompt. A disruption in independent signing was observed beginning in Session 90, which followed a 5-week intermission (for surgery). However, independent signing recovered when the filibuster to the model prompt was reduced to thirty s. Beginning with Session 99, sign training was extended across listeners, reinforcers, and settings. Sessions 99 to 101 were conducted by Experimenter 2 in the session room. During Sessions 102 to 104, Experimenter 2 conducted sessions in Heather's classroom. Her early on childhood educator conducted Sessions 105 to 107 in the classroom. Session 108 was conducted past Experimenter i at an indoor playground, and signing resulted in access to a riding toy. Session 109 was conducted past Experimenter 1 in the classroom, and signing resulted in admission to crackers. Independent signs remained high, with very few prompted signs, every bit new experimenters, reinforcers, and settings were introduced.

Heather's and Betty'due south prompted and independent signs per infinitesimal during baseline, sign grooming, and sign-training extension.

Numbers signal the filibuster to the model prompt. Sign-preparation extension sessions are marked with a bracket.

Betty's data also are depicted in Figure i. Betty did not sign during the initial baseline phase. During sign training, contained signing was first observed at the ten-s delay to the model prompt, and loftier levels of signing emerged and were maintained with very picayune prompting as the delay to the model prompt increased to 35 south. Independent signing decreased immediately during the render to baseline. Sign training was then reinitiated at the 5-s delay to the model prompt, and Betty's independent signing increased and was maintained at high levels, with very little prompting, equally the delay to the model prompt was increased. During Sessions 69 to 93, sign training was extended beyond listeners and settings. Sessions 69 to 81 were conducted past Experimenter 1 in Betty'southward classroom. Sessions 82 to 85 were conducted by her classroom instructor in her classroom. During Sessions 86 to 89, Betty'due south begetter conducted sessions in his office. Sessions xc to 93 were conducted past her father in their home. Independent signing remained loftier, with very few experimenter prompts, equally different experimenters and settings were introduced.

Experiment 2

In this experiment, we attempted to supplant baby crying and whining with signing. Signs were trained using procedures like to those described in Experiment 1, and crying and whining were placed on extinction.

Method

Participants and Setting

Participants were two typically developing infants who attended a full-24-hour interval infant and toddler program. Geoffrey was ten months one-time and did not communicate consistently through vocal or signed advice. Geoffrey was chosen for participation based on teacher report that he frequently cried when not receiving attending in the classroom. Therefore, sign preparation was conducted to teach Geoffrey a signed request for experimenter attention and an assortment of toys (e.1000., assurance, musical toys). Lyle was 9 months old and independently signed "more than" for access to preferred items (i.e., toys or nutrient). Lyle was chosen for participation because his mother reported that (a) he ofttimes cried when not existence held and (b) she frequently responded to the crying by picking him up. Baseline was synthetic to replicate these conditions, and sign preparation was conducted to supplant the crying with a sign ("up") that specified its reinforcer. Lyle's female parent served every bit the experimenter in all of his sessions. Sessions were conducted in a small-scale therapy room equipped with a i-way observation window. Sessions were 5 min in length and were conducted i to four times per 24-hour interval, 5 days per week. Sessions were scheduled then they did non interfere with children'southward daily routines (e.g., naps, meals).

Response Measurement and Interobserver Agreement

Observers recorded the frequency of independent and prompted signs. The target sign for Geoffrey was a modified version of the ASL sign "please" (defined every bit in Experiment i). The target sign for Lyle was the ASL sign "up," recorded when his left or right arm moved into a vertical position using an upward movement, with his fingers pointing towards the ceiling. Independent signs were those that occurred prior to an experimenter prompt. Observers too recorded the duration of crying and whining displayed past each of the participants.

Interobserver understanding was assessed by having a 2nd observer simultaneously but independently record data during a minimum of 32% of sessions for each participant (range, 32% to 39%). Agreement percentages were calculated as in Experiment 1. Hateful agreement beyond participants was 96% (range, 84% to 100%) for independent signing, 97% (range, 84% to 100%) for prompted signing, and 87% (range, 63% to 99%) for crying and whining.

Process

Baseline

Baseline was synthetic to replicate naturally occurring weather in which whining and crying served as a master form of advice. Thus, in these sessions, the reinforcer was presented contingent on crying or whining. For Geoffrey, experimenter attention and toys were delivered for xxx southward on a fixed-ratio (FR) 1 schedule for crying or whining. For Lyle, maternal attention (i.e., his mother held him and spoke to him) was delivered for fifteen s on an FR ane schedule for crying or whining.

Sign Grooming

When sign training was introduced, crying and whining no longer resulted in the designated reinforcer (i.due east., extinction). Otherwise, Geoffrey'due south sign-training procedures were identical to those described in Experiment ane. Lyle'southward sign-training procedures were similar except that only physical prompts were delivered (i.e., no model prompts were used) during initial training sessions. Get-go with Session 45, the model prompt was added at the 5-s filibuster, and thereafter, procedures were the aforementioned as those used with all other participants.

Experimental Design

The furnishings of sign training were evaluated past comparing baseline and sign-training atmospheric condition in a reversal design.

Results

Geoffrey's data are depicted in Figure 2. Geoffrey rarely signed during the initial baseline, and crying and whining occurred in every session. According to the programmed contingency, the experimenter provided attention immediately when whatsoever crying or whining was observed, and these responses typically ceased when experimenter attention was delivered. Therefore, crying and whining episodes were more often than not cursory and of low intensity. Afterward exposure to 55 sign-training sessions with the delay to prompting increasing in 5-s increments and inconsistent independent signing, we increased the delay to the model prompt in larger increments. We hoped that this modification would increase the reinforcing value of toys and attention because these events would be presented less frequently as a issue of the subtract in prompted signs. A gradual increase in independent signs was observed at the 2-min delay. A decrease in crying and whining occurred throughout the condition, with no crying and whining when independent signing was established at loftier rates (Sessions 80 to 88). The return to baseline resulted in a decrease in contained signing and an increase in crying and whining. Independent signing gradually recovered when sign training was reinitiated at the 5-south delay, and crying and whining decreased to very low levels. The delay was subsequently lengthened, and loftier rates of contained signing were maintained with very few prompted signs. In comparison to baseline, Geoffrey showed very low levels of crying in sessions in which he signed independently at high levels.

Geoffrey's prompted and contained signs per minute and duration (in seconds) of crying and whining Lyle's prompted and independent signs per minute and duration (in seconds) of crying and whining during baseline and sign preparation.

Numbers indicate the delay to prompting.

Lyle'south information are depicted in Figure 2. During baseline, variable levels of crying and whining occurred, with no independent signing. As with Geoffrey, Lyle'south crying and whining episodes were mostly brief and of low intensity during experimental sessions, but the duration and intensity of crying increased as the delay to the concrete prompt increased to 15 s. Therefore, we returned to the 10-s and 5-s delays, and crying and whining decreased temporarily. Subsequently, nosotros added a model prompt (as with the other participants) to the prompting sequence, and eventually crying decreased. Independent signing gradually increased at the 30-s filibuster to the model prompt and remained high at the 1-min delay. The duration of crying and whining decreased to very low levels when contained signing emerged. During the reversal to baseline, in that location was a gradual subtract in contained signing and an immediate increase in crying and whining. When sign training was reinstated at the iii-s filibuster to the model prompt, contained signing immediately increased to high levels and remained high through the 15-s filibuster to the model prompt. Crying and whining immediately decreased to very depression levels and remained low throughout the entire condition. Lyle's crying occurred at nigh zero simply when (a) he was prompted to sign immediately (i.e., 0-s filibuster) and (b) he signed independently at high levels.

General Discussion

In this study, delayed model and physical prompts and reinforcement of signing produced independent signing in 4 infants, including 1 infant with Down syndrome (Heather) and 1 baby who was just half dozen months old (Betty). Sign preparation may accept been particularly advantageous for Heather and Betty, for whom vocal advice was not expected for several months. The results of the present study and the Thompson et al. (2004) report bespeak that it is possible to teach an infant to perform a simple sign using delayed prompting and reinforcement.

The sign-training procedures used in the electric current study differed from those in the Thompson et al. (2004) study only in that model prompts were delivered in addition to physical prompts. Given that only physical prompts were used in Thompson et al., a preexisting imitative repertoire is not necessary for conquering of signing. Although model prompts are not an essential component of sign preparation, nosotros chose to include this course of prompting to capitalize on children's emerging imitative capabilities. In improver, in exercise, it may be wise to include model prompts when instruction preimitative children because the procedures used here for sign preparation closely resemble those shown to be effective in producing imitative behavior (e.g., Baer, Peterson, & Sherman, 1967). Despite these applied advantages of a multicomponent approach, a limitation of the study is that the experimental design does not allow the isolation of the functional components of the intervention.

The Thompson et al. (2004) written report was limited in that children were observed only under experimental conditions and with a single listener (the experimenter). Thus, three participants acquired signs, but the degree to which these responses served as functional communication was not demonstrated. Post-obit sign preparation in the current written report, children readily performed the target signs nether a variety of relevant stimulus conditions, and these data provide more convincing bear witness that these elementary motor responses served as functional communication. However, these data remain limited in at least two ways. Commencement, each child acquired only one sign. Time to come inquiry should be aimed at educational activity multiple signs, with each under control of relevant discriminative stimuli (e.thou., tacts) or establishing operations and consequences (i.e., mands). Second, the conditions necessary for signing to occur under a diverseness of atmospheric condition are unclear considering (a) signing was measured only under weather in which sign training was programmed and (b) baseline sessions were non conducted under all assessment weather condition. Therefore, it is unknown whether the effects of sign training generalized beyond listeners, settings, and evocative events.

Results of Experiment 2 showed that, when sign grooming was combined with extinction, a subtract in crying and whining was observed. Given that sign training and extinction were combined, it is not possible to isolate the effects of these individual components. However, existing research suggests that extinction was likely a functional component of of the intervention (Hagopian, Fisher, Sullivan, Acquisto, & LeBlanc, 1998; Wacker et al., 1990). In addition, it seems most appropriate to extinguish crying and whining only when an alternative form of communication is taught, and it is likely that potential negative side effects of extinction were minimized through this combined approach (Lerman, Iwata, & Wallace, 1999).

A vast body of research identifies language delays every bit a take chances factor for the development of beliefs problems (e.g., Beitchman et al., 1996; Benasich, Curtiss, & Tallal, 1993; Toppelberg & Shapiro, 2000). Given that children can learn signs every bit early as 6 months of historic period, sign training may contribute to the prevention of behavior problems for immature children at risk (e.g., developmental delays, language delays, sensory impairment). For typically developing children, sign training may but provide an effective means of communication several months earlier than those who rely solely on vocal communication. In add-on, teaching young infants to sign may testify to be scientifically valuable in that it gives researchers an additional method of evaluating a child'south linguistic communication abilities at a very young age. For example, developmental studies of symbolic beliefs take generally measured gestures or words displayed by children in the 2nd year of life (due east.g., Bretherton et al., 1981; Nanny & Waxman, 1998; Snyder, Bates, & Bretherton, 1981), presumably because gestural and vocal vocabularies exercise not typically develop until this time. Past introducing communication at a much before historic period, researchers will have the ability to monitor more closely infants' emerging capabilities.

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Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1868823/

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