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Purpose: We present the first study of echolalia in deaf, signing children with autism spectrum disorder (ASD). We investigate the nature and prevalence of sign echolalia in native-signing children with ASD, the relationship between sign echolalia and receptive language, and potential modality differences between sign and speech. Method: Seventeen deaf children with ASD and 18 typically developing (TD) deaf children were video-recorded in a series of tasks. Data were coded for type of signs produced (spontaneous, elicited, echo, or nonecho repetition). Echoes were coded as pure or partial, and timing and reduplication of echoes were coded. Results: Seven of the 17 deaf children with ASD produced signed echoes, but none of the TD deaf children did. The echoic children had significantly lower receptive language scores than did both the nonechoic children with ASD and the TD children. Modality differences also were found in terms of the directionality, timing, and reduplication of echoes. Conclusions: Deaf children with ASD sometimes echo signs, just as hearing children with ASD sometimes echo words, and TD deaf children and those with ASD do so at similar stages of linguistic development, when comprehension is relatively low. The sign language modality might provide a powerful new framework for analyzing the purpose and function of echolalia in deaf children with ASD., Echolalia is the phenomenon whereby children repeat or echo the utterances of others. It occurs in some typically developing (TD) children (Volkmar, Paul, Klin, & Cohen, 2005), in individuals with [...]

Purpose: Sign language users recruit physical properties of visual motion to convey linguistic information. Research on American Sign Language (ASL) indicates that signers systematically use kinematic features (e.g., velocity, deceleration) of dominant hand motion for distinguishing specific semantic properties of verb classes in production (Malaia & Wilbur, 2012a) and process these distinctions as part of the phonological structure of these verb classes in comprehension (Malaia, Ranaweera, Wilbur, & Talavage, 2012). These studies are driven by the event visibility hypothesis by Wilbur (2003), who proposed that such use of kinematic features should be universal to sign language (SL) by the grammaticalization of physics and geometry for linguistic purposes. In a prior motion capture study, Malaia and Wilbur (2012a) lent support for the event visibility hypothesis in ASL, but there has not been quantitative data from other SLs to test the generalization to other languages. Method: The authors investigated the kinematic parameters of predicates in Croatian Sign Language (Hrvatskom Znakovnom Jeziku [HZJ]). Results: Kinematic features of verb signs were affected both by event structure of the predicate (semantics) and phrase position within the sentence (prosody). Conclusion: The data demonstrate that kinematic features of motion in HZJ verb signs are recruited to convey morphological and prosodic information. This is the first crosslinguistic motion capture confirmation that specific kinematic properties of articulator motion are grammaticalized in other SLs to express linguistic features. Key Words: sign language, predicate, prosody, morphology, velocity, acceleration, phonology, Deaf, The process of parsing continuous reality into discrete events is an automatic component of human visual perception (Baldwin, Baird, Saylor, & Clark, 2001; Speer, Zacks, & Reynolds, 2007; Zacks & [...]

The acquisition of the movement aspect of American Sign Language signs was examined longitudinally in 9 young children of deaf parents. During monthly home visits, the parents demonstrated on videotape how their children formed the different signs in their lexicons. The parents also demonstrated how they formed or modeled these same signs. Overall, the children correctly produced 61.4% of the movements that were present in the adult sign models. Although the production accuracy of the movement aspect of signs did not improve over the course of the study, the number and complexity of movements produced by the children did increase as they got older and their vocabularies grew in size. Of the different sign movements, contacting action was by far the most frequently produced. The children were also relatively successful in their production of closing action and downward movement. The order of acquisition for the remaining ASL movements, however, was quite variable, with the exception that bidirectional movements tended to be produced more accurately than unidirectional movements. The relationship between children's early rhythmical motor behaviors and the development of sign movements is discussed. KEY WORDS: American Sign Language, deaf, movement, language acquisition, phonemes

This study was designed to evaluate the picture quality requirements for three visual communication modes: speechreading, fingerspelling, and sign language. Video recordings of everyday spoken, fingerspelled, and signed sentences were made, and some recordings were processed using a computer simulation of the IBIDEM technology: a videophone based on a novel type of visual sensor. This retina-like sensor, implemented in the camera, has a high resolution in the central part and a degrading resolution in the peripheral part of the picture. Two independent variables were examined: frame rate (10 and 15 frames per second) and spatial resolution (6000 and 8000 pixels per frame). Twenty-four people who were prelingually deaf participated, 8 in each communication mode. The results showed a marked effect of frame rate on speechreading. Fingerspelling and sign language were not affected by frame rate, and spatial resolution had no effect on any of the three communication modes. KEY WORDS: videotelephony, picture quality, speechreading, fingerspelling, sign language

The purpose of this investigation was twofold: (a) to determine if there are changes in specific temporal characteristics of speech that occur during simultaneous communication, and (b) to determine if known temporal rules of spoken English are disrupted during simultaneous communication. Ten speakers uttered sentences consisting of a carrier phrase and experimental CVC words under conditions of: (a) speech, (b) speech combined with signed English, and (c) speech combined with signed English for every word except the CVC word that was fingerspelled. The temporal features investigated included: (a) sentence duration, (b) experimental CVC word duration, (c) vowel duration in experimental CVC words, (d) pause duration before and after experimental CVC words, and (e) consonantal effects on vowel duration. Results indicated that for all durational measures, the speech/sign/fingerspelling condition was longest, followed by the speech/sign condition, with the speech condition being shortest. It was also found that for all three speaking conditions, vowels were longer in duration when preceding voiced consonants than vowels preceding their voiceless cognates, and that a low vowel was longer in duration than a high vowel. These findings indicate that speakers consistently reduced their rate of speech when using simultaneous communication, but did not violate these specific temporal rules of English important for consonant and vowel perception. KEY WORDS: simultaneous communication, signed English, fingerspelling, segment duration, pause duration

One of the natural methods of tactual communication in common use among individuals who are both deaf and blind is the tactual reception of sign language. In this method, the receiver (who is deaf-blind) places a hand (or hands) on the dominant (or both) hand(s) of the signer in order to receive, through the tactual sense, the various formational properties associated with signs. In the study reported here, 10 experienced deaf-blind users of either American Sign Language (ASL) or Pidgin Sign English (PSE) participated in experiments to determine their ability to receive signed materials including isolated signs and sentences. A set of 122 isolated signs was received with an average accuracy of 87% correct. The most frequent type of error made in identifying isolated signs was related to misperception of individual phonological components of signs. For presentation of signed sentences (translations of the English CID sentences into ASL or PSE), the performance of individual subjects ranged from 60-85% correct reception of key signs. Performance on sentences was relatively independent of rate of presentation in signs/sec, which covered a range of roughly 1 to 3 signs/sec. Sentence errors were accounted for primarily by deletions and phonological and semantic/syntactic substitutions. Experimental results are discussed in terms of differences in performance for isolated signs and sentences, differences in error patterns for the ASL and PSE groups, and communication rates relative to visual reception of sign language and other natural methods of tactual communication. KEY WORDS: deaf-blindness, tactual communication, sign language

This study determined whether the long-range outcome of first-language acquisition, when the learning begins after early childhood, is similar to that of second-language acquisition. Subjects were 36 deaf adults who had contrasting histories of spoken and sign language acquisition. Twenty-seven subjects were born deaf and began to acquire American Sign Language (ASL) as a first language at ages ranging from infancy to late childhood. Nine other subjects were born with normal hearing, which they lost in late childhood; they subsequently acquired ASL as a second language (because they had acquired spoken English as a first language in early childhood). ASL sentence processing was measured by recall of long and complex sentences and short-term memory for signed digits. Subjects who acquired ASL as a second language after childhood outperformed those who acquired it as a first language at exactly the same age. In addition, the performance of the subjects who acquired ASL as a first language declined in association with increasing age of acquisition. Effects were most apparent for sentence processing skills related to lexical identification, grammatical acceptability, and memory for sentence meaning. No effects were found for skills related to fine-motor production and pattern segmentation.

The purpose of this study was to investigate the effects of prosodic and gestural cues on children's lexical learning. Acquisition of novel words was examined under linguistic input conditions that varied in terms of rate of speech, stress, and use of supplemental visual cues (i.e., gestures). Sixteen kindergarten children served as subjects in this study, including 8 children with normal language (NL) and 8 children with specific language impairment (SLI). A repeated-measures design was used such that all subjects in both groups participated in each of the three experimental conditions (the Rate, Stress, and Visual Condition). Results indicated that acquisition of novel words by the groups with NL and SLI was significantly affected by alterations in speaking rate and by the use of gestures accompanying spoken language. There were no statistically significant effects for the stress manipulations, although subjects with SLI tended to correctly produce novel words that had received emphatic stress during training more often than words presented with neutral stress. Implications of these findings are discussed with respect to the importance of considering how the manner of presentation of the linguistic signal influences the processing and acquisition of language.

Previous studies investigating the organization of articulatory gestures present conflicting accounts of age-related differences in the execution of the articulatory gestures themselves and in the organization of those gestures. Several methodological differences may help to explain these contradictions: First, different studies have used different measures, all of which reflect vocal-tract activity to varying extents; second, the articulatory gestures being analyzed differed across studies; third, the phonetic composition of syllables has varied; and finally, utterance length, and therefore complexity, has varied across studies. The purpose of this study was to investigate the possibility that the reason these methodological differences have led to contradictory results is because the emergence of mature gestural patterns in children's speech is not uniform. To accomplish this goal, detailed acoustic analyses were performed on schwa-stop-vowel utterances from adults and from children (3, 5, and 7 years of age). Temporal measures showed that some acoustic segments were longer in children's than in adults' samples, whereas others were similar in duration. Formant frequencies indicated that vocal-tract opening and closing achieve adult-like patterns of movement by the age of 3 years, but children's tongue gestures are constrained by phonetic context more than those of adults until at least the age of 7 years. Taken together, these results suggest that the pace of development for learning to produce and to coordinate articulatory gestures is not uniform. Thus, the contradictions in findings among earlier studies may very well reflect differences in choices of measurement and utterances to be analyzed, both of which may lead to evaluations of different aspects of gestural patterning.

Hearing adults produced signed and spoken monologues under conditions of quiet or 80 dB SPL of noise and with their vision unobstructed or obstructed. Their signs were videotaped and a random sample of 24 frames was analyzed in each condition through a computer program that determined the overall distance of the hand from a marker placed on the signer's torso. Vocal intensity was digitized from the tape recordings and analyzed by computer for 1 min of continuous speech in each condition. The visual obstruction had no effect either on the distance of the signs or on the vocal intensity of their speech. The subjects increased vocal intensity by about 55% when the noise was introduced (the usual Lombard effect), but the noise had no effect on the distance of the signs. Sign performance was not influenced by visual feedback, and sign and speech were independent communication systems, even in bilingual speaking and signing subjects.

This study investigated the effects of reduced visibility on the distance of signing hands from the bodies of adult signers who are deaf and on their rates of sign production. Subjects were videotaped as they signed with partners in each of three experimental conditions: unimpeded, moderately impeded, and severely impeded visibility. Visual impedance was created by placing screens between signing partners. The distance of a hand from the body, in terms of lateral, vertical, and forward-depth dimensions, was determined from digitized measurements of single video frames randomly selected from those in which the subject was actively signing. Sign rate was calculated as the number of signsproduced in a given segment of time. Signs produced in the severely impeded visibility condition were found to be made at a slower rate and with a mean hand position further forward and vertically higher than signs produced in the unimpeded visibility condition.

Research suggests that people with intellectual impairments who use manual signs to augment or substitute for speech rarely progress beyond the stage of single signs and that word order is particularly problematic. However, the majority of studies have focused on experimental tasks, and relatively little is known about spontaneous sign production in naturalistic settings. The present study explored the linguistic development in sign and speech of 10 children who relied on manual signs (the Makaton vocabulary) as their main means of communication. Mean utterance length in sign ranged from 1.0 to 2.5, and analysis of semantic relations, lexical development, and word order suggested that the children had not developed their language beyond MLU Stage I. Examination of their abilities within the modality of sign indicated that some children were able to manipulate features of sign at a sublexical level. The results are discussed in relation to the language input by teachers, and inferences are drawn regarding the underlying modality of linguistic representation in children who use manual signs. KEY WORDS: intellectual impairment, language development, manual sign, augmentative and alternative communication, word order., Studies of atypical populations provide us with naturally occurring situations to test hypotheses about the generality of development of linguistic skills (Hodapp & Burack, 1990). Children with intellectual impairments who [...]