An experimental analysis of linguistic development: the productive use of the plural morpheme

Operant conditioning procedures were used to establish a generative use of the plural morpheme in the speech of a severely retarded girl. During training trials, reinforcement was presented contingent upon correct imitation of singular and plural verbalizations by the experimenter, in response to objects presented to the subject singly and in pairs. A generative productive plural usage resulted, the girl correctly labeling new objects in the singular or plural without further direct training relevant to those objects. After establishing the singular/plural usage, the contingencies were reversed (reinforcement of plural responses to single objects, and vice-versa). This produced a corresponding reversal of response by the child. The original usage was then recovered by returning to the previous contingencies. A second experiment analyzed certain error responses occurring during the first experiment, and further probed the generative nature of the subject's plural usage. It was found that errors were somewhat more likely to occur in the pluralization of words ending in vowels than of words ending in consonants. Furthermore, several words whose plurals had been learned according to the reversed plural rule, when examined later during reinforcement of normal plural usage, were found then to exemplify the normal rule being reinforced, yet without direct training.     

PRODUCING GENERATIVE SENTENCE USAGE BY IMITATION AND REINFORCEMENT PROCEDURES1

Three retarded subjects and two developmentally normal toddlers were trained using imitation and reinforcement procedures to use correct sentences. The experimental task was to use sentences with correct subject-verb agreement to describe pictures that were presented to the subjects. Two classes of sentences were taught: those involving a plural subject that required the use of the verb “are” (for example, “the boys are running”) and those involving a singular subject that required the use of the verb “is” (for example, “the boy is running”). The basic design of the study involved multiple baselines for each class of sentences. Four of the subjects began to produce novel, untrained sentences of a particular type to generalization probe pictures when that particular class of sentence was currently being trained. Thus, the imitation and reinforcement procedures appeared to be functional in producing generative sentence usage for both types of sentences. One subject produced correct sentences to both singular and plural probe pictures when only “is” sentences had been taught. A reversal procedure and retraining phase indicated that for this subject, imitation and reinforcement procedures for training one class of sentence behavior seemed functional in producing generative responses of the other class of sentences.     

Remembering plurals: Unit of coding and form of coding during serial recall

Subjects were required to recall lists of six words which had been presented visually in sequence. One or two of the words might be plural nouns. A substantial number of errors occurred in which the plural form became detached from its original root. This is taken as evidence for a morpheme-based code as opposed to a unitary word code. A significantly high proportion of these errors maintained the form of the plural ( /S/, /Z/ or (ЪZ/) which is considered evidence for a primarily phonological coding of the plural morpheme. There is however a suggestion that on some occasions the plural is coded morphemically—i.e., in a way which does not distinguish between the various plural endings.     

Continuation of training as a variable influencing the generalization of speech in a retarded child

Imitation and differential reinforcement were applied in training a speech-deficient retarded child 4 separate verbal answers to 4 “everyday” questions. Training was provided in only one setting with one experimenter. After the subject had acquired each answer-response in the training situation, probes for stimulus generalization were given by both the trainer and nontrainers. These probes tested the usage of both trained and nontrained question-answering responses under nontraining conditions. Use of the separately trained responses in nontraining contexts increased as training continued beyond the established learning criteria. A concurrent reinforcement procedure for all 4 answerresponses increased the overall generalization effects across individuals and settings; the use of differential reinforcement of nonverbal responses in the training setting decreased the overall generalization effects.     

Mode-relations in language learning by language-deficient retarded subjects

The relationship between language comprehension and production was examined with two severely language-deficient retarded subjects who were taught the plural form /z/. Comprehension and production were trained concurrently with different words in each mode until correct plural use occurred in the untrained mode for each word. Subsequent training of reversed plural use in comprehension for one subject and production for the other failed to result in reversed plural use in the untrained modes for those words. This mode-independence contrasted with interdependence displayed by normal children in earlier study using similar procedures. The results are discussed in relation to the normal developmental process and the possible deviation from it.     

Effects of variable-interval value and amount of training on stimulus generalization.

In Experiment 1 pigeons pecked a key that was illuminated with a 501-nm light and obtained food by doing so according to a variable-interval (VI) schedule of reinforcement, the mean value of which differed across groups: either 30 s, 120 s, or 240 s. The pigeons in all three groups were trained for 10 50-min sessions. Generalization testing was conducted in extinction with different wavelengths of light. Absolute and relative generalization gradients were similar in shape for the three groups. Experiment 2 was a systematic replication of Experiment 1 using line orientation as the stimulus dimension and a mean VI value of either 30 s or 240 s. Again, gradients of generalization were similar for the two groups. In Experiment 3 pigeons pecked a key that was illuminated with a 501-nm light and obtained food reinforcers according to either a VI 30-s or a 240-s schedule. Training continued until response rates stabilized (> 30 sessions). For subjects trained with the 30-s schedule, generalization gradients were virtually identical regardless of whether training was for 10 sessions (Experiment 1) or until response rates stabilized. For subjects trained with the VI 240-s schedule, absolute generalization gradients for subjects trained to stability were displaced upward relative to gradients for subjects trained for only 10 sessions (Experiment 1), and relative generalization gradients were slightly flatter. These results indicate that the shape of a generalization gradient does not necessarily depend on the rate of reinforcement during 10-session single-stimulus training but that the effects of prolonged training on stimulus generalization may be schedule dependent.     

Some attractions of verb agreement

In English, words like scissors are grammatically plural but conceptually singular, while words like suds are both grammatically and conceptually plural. Words like army can be construed plurally, despite being grammatically singular. To explore whether and how congruence between grammatical and conceptual number affected the production of subject-verb number agreement in English, we elicited sentence completions for complex subject noun phrases like The advertisement for the scissors. In these phrases, singular subject nouns were followed by distractor words whose grammatical and conceptual numbers varied. The incidence of plural attraction (the use of plural verbs after plural distractors) increased only when distractors were grammatically plural, and revealed no influence from the distractors' number meanings. Companion experiments in Dutch offered converging support for this account and suggested that similar agreement processes operate in that language. The findings argue for a component of agreement that is sensitive primarily to the grammatical reflections of number. Together with other results, the evidence indicates that the implementation of agreement in languages like English and Dutch involves separable processes of number marking and number morphing, in which number meaning plays different parts.     

A functional analysis of receptive language and productive speech: acquisition of the plural morpheme

Operant conditioning procedures were applied to two retardates to establish receptive auditory plurals: correct pointing to single or paired objects was reinforced after hearing singular or plural labels. This training proceeded until an errorless (generative) criterion of correct performance was achieved. Unreinforced probes measuring expressive use of singulars and plurals were interspersed in this receptive training. Neither subject generalized from this receptive training to expressive plurals, in that each used singulars when labeling pairs. Then, both subjects were directly trained in conventional expressive plurals to an errorless (generative) criterion. The previous design was then repeated, but the receptive repertoire was reversed: pointing at pairs in response to singular labels was reinforced, and vice-versa. Unreinforced probes of expressive plural usage again showed its independence of the current receptive repertoire in that conventional (unreversed) plural usage was displayed. Thus, the independence of the expressive repertoire (even when unreinforced) from the reinforced patterns of the receptive repertoire was demonstrated.     

Fluency Training in Phoneme Blending: A Preliminary Study of Generalized Effects

We examined the generalized effects of training children to fluently blend phonemes of words containing target vowel teams on their reading of trained and untrained words in lists and passages. Three second-grade students participated. A subset of words containing each of 3 target vowel teams (aw, oi, and au) was trained in lists, and generalization was assessed to untrained words in lists, trained and untrained words in target passages, and novel words in generalization passages. A multiple probe design across vowel teams revealed generalized increases in oral reading accuracy for target words presented in both lists and passages for all 3 students on 2 vowel teams and for 1 student on all 3 vowel teams. Generalized increases in oral reading fluency in both lists and passages were found for all 3 students on the vowel team that was trained to a fluency criterion, with two students showing increases prior to training on the other two vowel teams. Implications of these results for building fluency in prerequisite phonemic awareness skills as an intervention for promoting generalized oral reading fluency are discussed.     

PARENTAL TRAINING OF THE PLURAL MORPHEME IN NORMAL TODDLERS1

Experimental studies with young normal children can provide useful strategy for the functional analysis of language. Research by Whitehurst (Journal of Experimental Child Psychology, 1972, 13 , 502–515) exemplifies this approach, in which 2-yr-old children were exposed to a training procedure that involved imitation and differential reinforcement for a two-word productive sequence of the adjective-noun form. Results indicated that these young children could be trained to produce rudimentary novel utterances that were grammatically appropriate. More recently, Hursh and Sherman (Journal of Experimental Child Psychology, 1973, 15 , 328–339) reported the existence of a functional relationship between parental modelling and reinforcement of vocalizations, and increased instances of these vocalizations in young (15- to 20-month-old) children. These demonstrations relate to a summary of findings with linguistically deviant populations discussed by Sherman (Advances in Child Development, 1971). The present study attempts to extend these “generative” investigations to normal children and to provide useful information for those interested in teaching speech forms to them. Modelling and differential reinforcement were used by three mothers to establish the use of the plural morpheme in the speech of their 19- to 25-month-old children. During training trials, verbal praise was presented contingent on correct labelling of singular and plural items, while correct labelling was modelled if the child responded incorrectly. Children learned to label specifically trained sets of singular and plural items and also exhibited correct labelling when asked to label never-trained singular and plural items. After establishing correct usage, the same training procedures were used to train reversed labelling (plural responses to single items and singular responses to plural items). This produced a corresponding reversal of responding (both trained and untrained items) by each child for the plural items but not for singular items. Correct singular and plural labelling was recovered by returning to the initial procedures.     

Usage-based account of the acquisition of liaison: evidence from sensitivity to the singular/plural orientation of nouns

This study investigates whether children’s production and recognition of obligatory liaison sequences in French depend on the singular/plural orientation of nouns. Certain nouns occur more frequently in the plural (e.g., arbre “tree”), whereas others are found more often in the singular (e.g., arc-en-ciel “rainbow”). In the input, children more frequently encounter these plural-oriented nouns after determiners that indicate plurality (e.g., les,des “the”, deux “two”) and that are often associated with a /z/ liaison (e.g., deux arbres [døzarbr] “two trees”). In Experiment 1, 122 children (3 years 2 months to 6 years 3 months of age) were asked to produce nominal phrases with either /z/ liaisons (i.e., in plural contexts such as deux ours [døzurs] “two bears”) or /n/ liaisons (i.e., in singular contexts such as un ours [nurs] “one bear”). We found correlations between the plural orientation of the nouns and (a) the probability that they will be preceded by an incorrect /z/ liaison in the singular context and (b) the probability that they will be preceded by a correct /z/ liaison in the plural context. This result was, however, restricted to the younger children. In Experiment 2, 20 children (5 years 5 months to 6 years 3 months of age) were asked to monitor target words in auditorily presented sentences. The results showed shorter reaction times for singular-oriented nouns when preceded by a singular determiner than when preceded by a plural determiner. Conversely, plural-oriented nouns were responded to faster when preceded by a plural determiner than when preceded by a singular determiner. Results are discussed within the framework of a two-stage model of liaison acquisition recently proposed by Chevrot, Chabanal, and Dugua (Journal of French Language Studies,17 [2007] 103-128) as well as by Chevrot, Dugua, and Fayol (Journal of Child Language [in press]).     

Rapid word identification in pure alexia is lexical but not semantic

Following the notion that patients with pure alexia have access to two distinct reading strategies-letter-by-letter reading and semantic reading-a training program was devised to facilitate reading via semantics in a patient with pure alexia. Training utilized brief stimulus presentations and required category judgments rather than explicit word identification. The training was successful for trained words, but generalized poorly to untrained words. Additional studies involving oral reading of nouns and of functors also resulted in improved reading of trained words. Pseudowords could not be trained to criterion. The results suggest that improved reading can be achieved in pure alexia by pairing rapidly presented words with feedback. Focusing on semantic processing is not essential to this process. It is proposed that the training strengthens connections between the output of visual processing and preexisting orthographic representations.     

Development of syntax in a retarded girl using procedures of imitation, reinforcement, and modelling

Three experiments demonstrated the development and generalized use of a singular and plural declarative sentence in a child initially lacking sentence form responses. In each experiment, an adult(s) served as a language model(s), and consequences (sweets) were provided for imitation of the model. During training trials, an item(s) was displayed first to the model(s) then to the subject; these displays were accompanied by requests to label the item(s). Generalization was assessed by a number of probe trials that were periodically interspersed among training trials. During these trials, the subject was requested to label the displayed item(s) without any preceding labelling response from the model. Using these procedures, generalized use of a singular sentence ("That is one-") resulted in Experiment I, and generalized use of a plural sentence ("These are two-") resulted in Experiment II. In Experiment III, two models (a singular and a plural sentence model) were made available to the subject but imitation of only one model was reinforced during any one condition. Results indicated the subject labelled probe (generalization) items with the same sentence form that was modelled and reinforced during training trials.     

Modification of articulation errors of pre-delinquents by their peers

Pre-delinquent peers in Achievement Place (a community based family style rehabilitation program based on a token economy) were given points (token reinforcement) to modify the articulation errors of two boys. In Experiment I, using a multiple baseline experimental design, error words involving the /l/, /r/, /th/, and /ting/ sounds were successfully treated by both a group of peers and by individual peers. Also, generalization occurred to words that were not trained. The speech correction procedure used by the peers involved a number of variables including modelling, peer approval, contingent points, and feedback. The individual role of each of these variables was not experimentally analyzed, but it was demonstrated that peers could function as speech therapists without instructions, feedback, or the presence of an adult. It was also found that payment of points to peers for detecting correct articulations produced closer agreement with the experimenter than when they were paid points for finding incorrect articulations. The results were replicated in a second experiment with another subject who had similar articulation errors. In addition, the second experiment showed that peer speech correction procedures resulted in some generalization to the correct use of target words in sentences and significant improvements on standard tests of articulation.     

Establishing generalized verb-noun instruction-following skills in retarded children

A transfer of stimulus control procedure was used to establish generalized verb-noun instruction-following skills in two severely retarded boys. Each of 12 verbs was trained, in a multiple baseline order, to criterion with each of 12 nouns in the form of verb-noun verbal instructions. Throughout training, reinforced probes were conducted on both trained and untrained verb-noun combinations. As training progressed, both subjects began to respond correctly to untrained verb-noun instructions. Eventually, a verb needed to be trained in combination with only one noun before generalization occurred to the as-yet-untrained 11 verb-noun instructions involving that verb.     

An analysis of individual differences in generalization between receptive and productive language in retarded children

Retarded subjects were taught generative pluralization rules concurrently in both the receptive and productive modalities of language. Receptive training established correct pointing to either one or a pair of objects, in response to a spoken singular or plural label of the object(s); productive training established correct spoken labels of one or a pair of objects presented visually. However, these pluralization rules were established in each modality only for a specific class of plurals: those ending in -s for one modality, those ending in -es for the other modality. This training was successful in establishing generative, or rule-governed behaviors, such that untrained examples of singulars and plurals were usually responded to correctly. Nevertheless, despite this concurrent, generative behavior, probes revealed little generalization between modalities: three of four subjects did not generalize clearly from receptive training with one class of plurals to correct productive use of that class, nor did they generalize from productive training of the other class of plurals to correct receptive response to that class. The fourth subject, however, did show strong generalization of both these types. It was concluded that automatic generalization between receptive and productive language is not necessarily an inevitable result of language training in such subjects, and therefore may require explicit, if temporary, programming, such as by direct reinforcement.     

GENERALIZING ARTICULATION TRAINING WITH TRAINABLE MENTALLY RETARDED SUBJECTS1

A multiple-baseline technique was used to evaluate generalization effects during articulation training with trainable mentally retarded subjects. Four target words were selected for each subject on the basis of whether the subject could articulate the word correctly when it was modelled but could not articulate the word correctly in response to a picture of it. Five different settings were selected for generalization probing and training for each subject. In Setting 1, Experimenter 1 initiated training sequentially on all four target words for each subject. Other experimenters probed for correct articulation generalization in four other settings. Training was initiated in these four other settings sequentially only if correct responding failed to generalize to a setting. Results indicated that it was necessary to initiate training on at least three of the four selected target words in at least one additional setting with an additional trainer before correct responding generalized to untrained settings.     

THE ROLE OF SUBJECT VERBALIZATION IN GENERALIZED CORRESPONDENCE

We examined the role of subject verbalization in the generalization of verbal-nonverbal correspondence. Twelve kindergarten children underwent correspondence training (subject verbalization) or received reinforcement for performing an experimenter-selected behavior (experimenter verbalization). A reversal design, along with the introduction of a multiple baseline design across behaviors, was used to assess functional relations. Pupils who received correspondence training demonstrated greater generalization. Our findings suggest that subject verbalization may be necessary to accomplish generalized correspondence.     

Deaf and hearing children's plural noun spelling

The present study examines deaf and hearing children's spelling of plural nouns. Severe literacy impairments are well documented in the deaf, which are believed to be a consequence of phonological awareness limitations. Fifty deaf (mean chronological age 13;10 years, mean reading age 7;5 years) and 50 reading-age-matched hearing children produced spellings of regular, semiregular, and irregular plural nouns in Experiment 1 and nonword plurals in Experiment 2. Deaf children performed reading-age appropriately on rule-based (regular and semiregular) plurals but were significantly less accurate at spelling irregular plurals. Spelling of plural nonwords and spelling error analyses revealed clear evidence for use of morphology. Deaf children used morphological generalization to a greater degree than their reading-age-matched hearing counterparts. Also, hearing children combined use of phonology and morphology to guide spelling, whereas deaf children appeared to use morphology without phonological mediation. Therefore, use of morphology in spelling can be independent of phonology and is available to the deaf despite limited experience with spoken language. Indeed, deaf children appear to be learning about morphology from the orthography. Education on more complex morphological generalization and exceptions may be highly beneficial not only for the deaf but also for other populations with phonological awareness limitations.     

Voice Onset Time in Ataxic Dysarthria

In eight patients with a purely ataxic syndrome due to cerebellar atrophy the voice onset time (VOT) of word-initial stop consonants was measured at the acoustic signal. The subjects had been asked to produce sentence utterances including either one of the German minimal pair cognates “Daten” (/datn/, “data”) and “Taten” (/tatn/, “deeds”). In addition, a master tape comprising the target words from patients and controls in randomized order was played to six listeners for perceptual evaluation. Two major findings emerged. First, the cerebellar subjects presented with a reduced categorical distinction of the VOT of voiced and unvoiced stop consonants. Second, the patients' target words with initial unvoiced plosive gave rise to a significantly increased number of misassignments at perceptual evaluation. To some extent comparable VOT disruptions have been noted in apraxia of speech and basal ganglia disorders. Thus, different pathomechanisms might result in similar VOT abnormalities.