Natural Environment Teaching (NET)
The Importance of Chit-Chat in Language Development
Behavior analysts are known for using extrinsic reinforcers to change behavior, notably: points, tokens, food, drinks, and so on contingent upon correct responding. However, many behavior analysts prefer to use intrinsic reinforcers, sometimes referred to as natural reinforcers over extrinsic reinforcers when teaching language. Natural Environment Teaching occurs when behavior is shaped using the opportunity to engage in a inherently reinforcing activity. Here are some examples:
The Premack Principle:
David Premack was a psychologist who demonstrated that preferred activities could be used to reinforce participation in less preferred activities. The Premack principle uses a behavior that occurs at a higher frequency to reinforce a behavior that occurs at a lower frequency.
Common applied examples: You can play basketball when you complete your homework; when the entire class lines up quietly, we will go to recess.
Incidental Teaching:
Incidental Teaching, developed by Hart & Risley, emerged as a more child-centered approach that built upon the Premack Principle. It emphasized creating natural learning opportunities within the child's environment based on their interests.
Incidental Teaching begins when the child initiates an interaction. It can be used to teach vocabulary, to express ideas, to make requests and so on. It can be used to teach colors, shapes, numbers, letters, and sounds. Parents and teachers can use Incidental Teaching throughout the day in naturally occurring situations. According to Obrien et. al, (1979) follow these steps:
When the child speaks to you give the child your full attention.
A child comes to you and says, “Ball?” and points to one of two balls on the shelf. Ask a question about what the child said that expands the verbal response. “Ball?, You want the ball?, do you want to bounce the blue ball or the green one?” “Green”. “ Can you say, “I want the green ball?” Johnny replies, “Want green ball”. Ok, Johnny here’s the green ball.
Here is another example: Johnny comes to you and says, “Go outside?”
”Ok”, you reply, “what do you wear before going outside?” “Shoes?”, says Johnny. You reply, “That’s right, shoes. Put your shoes on before you play outside”. Johnny complies and you let him outside to play.
Pivotal Response Teaching (PRT)
Incidental teaching proved to be an effective teaching procedure. The problem was waiting for the child to initiate the interaction. Johnny might come to you because he wants X, but he might not initiate again for 10 minutes, or longer. Not a fast teaching technique. Consequently, the next step in the evolution of NET was to bait the child so s/he would initiate frequently. In 1987 PRT was known as the Natural Language Paradigm by Robert & Lynn Koegel et.al. Here the baiting part of the procedure, i.e., the presentation of a variety of preferred toys and activities, was used. After adding greater attention to ‘multiple cues’ and inserting maintenance tasks into a teaching session NLP became Pivotal Response Teaching (PRT) around 1991. These dates are approximate.
Laura Schreibman, Wendy Kaneko and Robert Koegel (1991) trained parents to use PRT to develop language skills in children with autism. They allowed the child to chose the activity, they interspersed maintenance tasks with new tasks to foster participation, they reinforced the child’s attempts to respond correctly even if the response was imperfect; they promoted frequent turn taking with the child; and the used reinforcers inherent in the task instead of external reinforcers. A more detailed description follows.
Here are the steps involved in PRT:
1. Set the stage - present a variety of preferable toys or fun activities.
2. Have the child choose the toy or activity.
3. Let the child play with the toy for 15-30 seconds.
4. Say, “My turn” take the toy and demonstrate what you want the child to do and say what you are doing, “I’m going to bounce the red ball into the red box. There, now what are you going to do?”
5. Wait for the child to respond. Your target response may be “I’m going to bounce the red ball into the red box”, but the child may say “ball in box” or simply “ball”. The response doesn’t have to be perfect. Reinforce a range of approximate verbal responses toward your target. Shape up the approximate responses to eventually meet your target criterion. After the child responds correctly, “I’m going to bounce the ball into the box” or imperfectly, “I bounce ball” reinforce the behavior by saying, “That’s right you’re going to bounce the red ball into the red box, nice talking". Then give him the ball and let Johnny bounce it.
6. Correction Procedure. If the child does not respond or responds incorrectly, prompt the correct response (whisper, point, use a physical prompt, model), praise mildly the prompted response then have the child continue with the activity. Wait 15-30 seconds. Bait (establish the motivational operation) by blocking the play response. Wait for a self initiated approximately correct response. Reinforce an unprompted response with continued play. Repeat as needed.
7. Let the child continue to play for about 15 sec.
8. Say, “My turn” and take the toy or block his play and begin the next trial, “I’m going to …….”. (See Step 4).
9. Intersperse maintenance trials. As you are shaping more sophisticated verbal responses, after every third or fourth trial require a verbal response that is easy (but not too easy) for the child to make. This helps keep the child participating in the activity.
10. Shape the child to talk about and respond to various aspects of the toys. “Push the big blue ball”. Objects have characteristics, they are small, tall, rough, smooth, yellow, striped and so on. Encourage the child to attend to those features by directing your questions to those multiple characteristics. Have the child attend to multiple cues. For example, at first, the child says,”ball”. Over teaching sessions require more sophisticated responses until you reach your target, “I’m going to bounce the big blue ball” and he does so. Over time, present small and large balls, balls of various colors, balls made of plastic, leather, and rubber. We want the essential features of an object to control verbal responding, not the irrelevant features. So keep the relevant features constant and vary the irrelevant features.
When the child is tired of the game, stop. The activity is only reinforcing if the child enjoys the activity. If not, stop. Have the child pick another activity. It’s common if interest in an activity lasts about 15 minutes for a 3 - 5 year old. You may be able to string two or three different activities together.
PRT identifies "pivotal" areas of development, such as motivation, self-regulation, and responding to multiple cues. I would include also imitation, language (i.e., manding, tacting, interverbals), following instructions and other skill areas. These pivotal areas are considered critical for a wide range of skill development.
The Importance of Chit-Chat
Within this post is a YouTube video of Todd Risely interviewed by an unnamed college professor. It’s over an hour long but worth viewing. Todd Risely and Mary Hart wrote two books discussed in the video. One is Meaningful Differences In The Everyday Experience of Young American Children (1995) and The Social World of Children Learning To Talk (1999). The two books discuss the results of their longitudinal research on the emergence of language in typical children. They sent observers into the homes of 42 families with new babies. They assigned families to one of three groups: educated and affluent families, families on public assistance, and working class families. None of the children were diagnosed with autism or a developmental disability. Again, these were families with typical children.
No parents from any of the 3 groups used Incidental Teaching, Pivotal Response Teaching or any other specific technique to develop language in their children. They were not converting naturally occurring teachable moments into language enrichment. Instead, they waited for the child’s language to develop on its own.
Risley describes two types of families that were found in all three groups: talkative families and taciturn families. Taciturn families had parents who were relatively uncommunicative in speech, saying little. Hart and Risley discussed two general types of speech the research team observed: business versus chit-chat. Business speech referred to language designed to make things happen, e.g., come here, put your shoes on, have some milk, let’s change your diaper and so on. This was the predominant speech observed in taciturn families. Within taciturn families there was relatively little chit-chat conversation.
Chit-chat refers to non-directive conversational speech. A talkative mother talked to the child while she was feeding, bathing, cleaning, preparing, that is, doing the ordinary things parents do with their children. She practiced speech with her child throughout the day. Speaking was a “dance” between parent and child. Talkative families engaged in business speech as much as the taciturn families, however the talkative families spent much more of their time engaged in chit-chat with their child. Consequently, the children from talkative families had more sophisticated speech and a much larger vocabulary than the taciturn families.
“But the differences in amount of language were greater than simply difference in language style. Some families not only talked more at each opportunity but talked more often, they interacted more often and responded and initiated more often to their children. We saw some parents who talked continuously as they fed, dressed, or changed their babies and others who did so with only a few introductory and closing remarks. Moreover, the amount of talking the family did seemed to be part of the culture being transmitted to the child. After the children learned to talk, and had all the skills needed to talk more than the family, they did not, the amount they talked stopped increasing as soon as they began to talk the amount typical of the family. (Meaningful Differences, p. 59).
At about 28 months the rate of child talking levels off to match the amount of talking in the household.
From 11 to 18 months old the average number of utterances parents spoke to their children was 325 per hour. The range was 56 to 793. At 29 to 36 months of age parent utterances ranged from 34 to 783 per hour.
Hart and Risley reported, “A child spoken to 50 times per hour will hear 700 utterances; a child spoken to 800 times per hour will hear more than 11,000 utterances. ….It is staggering to think of what 365 similar days in a year would produce interms of cumulative experience with language: exposure to 250 thousand utterances versus 4 million utterances. ….The implication for cumulative experience become yet more staggering”.
Hart and Risley estimated the amount of language experience.
“By age 3 the children in the professional families heard more than 30 million words, the children in working class families heard 20 million words, and the children from welfare families 10 million”.
At 3 years of age vocabulary growth, vocabulary use, and IQ test scores on the Stanford-Binet were obtained. Vocabulary size was consistently correlated with the measures of parent interactions. Vocabulary use was defined as the number of different words a child used per hour at 34-36 months of age. (p143). The greater the number of different nouns, adjectives, adverbs, and functions of words used the greater the vocabulary and IQ of the child at age 3. Hart and Risley also note that the families where business language was used primarily had a negative correlation with accumulation of vocabulary at age 3. Parents who relied on imperatives and prohibitions and less on the “dance” of chit-chat had children with reduced vocabulary and lower IQ scores. Socio-economic status was also correlated with vocabulary and IQ but was viewed as a lesser factor since the correlations between parent interactions, vocabulary, and IQ were higher.
Implications For Parents and Teachers
During the 1960s Hart and Risley began their study of language at the Turner House preschool that served disadvantaged families. There they developed incidental teaching methods designed to improve a child’s language skills. They also studied children who attended the University of Kansas laboratory preschool. The incidental teaching methods proved effective in improving the language of the disadvantaged children. However, the disadvantaged children did not quite catch up to the development of the advantaged families.
“We could easily increase the size of the children’s vocabularies by teaching them new words but we could not accelerate the rate of vocabulary growth so that it would continue beyond direct teaching.”
Hart and Risley wanted to know why. Why were they not able to change the developmental trajectory of the disadvantaged children?
Hart and Risley concluded that it was the metaphorical “dance” between parent and child, that is the “chit-chat” during the ages of birth to three, that had the greatest influence on vocabulary growth. The amount of chit-chat had a greater influence on developing vocabulary than socio-economic status. The more parents conversed with their children outside of business “get things done” conversations, the larger child’s vocabulary. They didn’t have to know how to do incidental teaching, or pivotal response teaching. These were typical children. The critical feature was amount. Parents who talk while going about their daily activities expose their children to 1000 - 2000 words every hour, enough to develop a burgeoning vocabulary.
References
Brown, W., (1999) Book Review: The Social World of Children Learning to Talk B. Hart & T.R. Risley, Baltimore Brookes 1999. Topics in Early Childhood Special Education 19:4
Hart & Risley (1968) Incidental Teaching (Social World of Children Learning to Talk).
Hart B., & Risley (1995) Meaningful Differences In The Everyday Experience of Young American Children, Brooks Press.
Hart B., & Risley (1999) The Social World of Children Learning To Talk, Brooks Publishing Co.
Koegel K. L., & Koegel L.K. (2006) Pivotal Response Treatments for Autism Brooks Publishing Co.
Mabry, J.H., (1997) Review of Hart and Risley’s Meaning Differences in the Everyday Experience of Young American Children. The Behavior Analyst 20, p. 25-30