Sue Peppé

Prosody in autism spectrum disorders: a critical review

BACKGROUND Many individuals with autism spectrum disorders present with unusual or odd-sounding prosody. Despite this widely noted observation, prosodic ability in autism spectrum disorders is often perceived as an under-researched area. AIMS This review seeks to establish whether there is a prosodic disorder in autism, what generalizations can be made about its various manifestations and whether these manifestations vary according to the diagnosis. A literature review was carried out to establish what areas of prosody in autism spectrum disorders have been researched to date, what the findings have been and to determine what areas are yet to be researched. MAIN CONTRIBUTION It is shown that prosody in autism spectrum disorders is an under-researched area and that where research has been undertaken, findings often conflict. The findings of these conflicting studies are compared and recommendations are made for areas of future research. CONCLUSIONS Research in this area has covered mostly prosodic expression, although some more recent studies cover comprehension, processing and the relationship of receptive prosodic ability to theory of mind. Findings conflict and methodology varies greatly.

Intonation development from five to thirteen.

Research undertaken to date suggests that important developments in the understanding and use of intonation may take place after the age of 5;0. The present study aims to provide a more comprehensive account of these developments. A specially designed battery of prosodic tasks was administered to four groups of thirty children, from London (U.K.), with mean ages of 5;6, 8;7, 10;10 and 13;9. The tasks tap comprehension and production of functional aspects of intonation, in four communicative areas: CHUNKING (i.e. prosodic phrasing), AFFECT, INTERACTION and FOCUS. Results indicate that there is considerable variability among children within each age band on most tasks. The ability to produce intonation functionally is largely established in five-year-olds, though some specific functional contrasts are not mastered until C.A. 8;7. Aspects of intonation comprehension continue to develop up to C.A. 10;10, correlating with measures of expressive and receptive language development.

Assessing intonation and prosody in children with atypical language development : the PEPS-C test and the revised version

A procedure for assessing prosody and intonation in children (PEPS‐C: Profiling Elements of Prosodic Systems—Children), suitable for use by clinicians with both children and adults, is described. The procedure includes testing of four communication areas in which intonation/prosody has a crucial role: interaction, affect, boundary (chunking) and focus. Each area has parallel tasks for assessing understanding and expression of the functions and ability to discriminate and articulate the prosodic forms involved. The original and revised forms of the test are compared, with some discussion of procedural considerations. Past and present uses of the test and future applications are considered.

Why is prosody in speech-language pathology so difficult?

An important question for speech-language pathologists is how best to define and characterize atypical prosody, with the eventual aim of designing effective intervention for it. With a view to investigating why prosodic atypicality should be hard to define and what considerations a speech-language pathologist should keep in mind, this paper begins by setting out some established functions of prosody and the forms that convey them, and goes on to review the neurological bases of prosodic disorder and some of the conditions in which prosodic disorder is known to occur. Factors in the perception of prosodic disorder are discussed, including the relationship between prosody and other aspects of communication, to identify the problems of distinguishing between prosody and interacting factors. The relationship between phonological prosodic categories and disordered prosody is considered, i.e., the problems of assigning disordered prosody to these categories for clinicians. Current methods of assessment, transcription and approaches to treatment are briefly considered, and an evaluation is made of how much progress has been made towards answering the initial question.

The Integration of Prosodic Speech in High Functioning Autism: A Preliminary fMRI Study

Background Autism is a neurodevelopmental disorder characterized by a specific triad of symptoms such as abnormalities in social interaction, abnormalities in communication and restricted activities and interests. While verbal autistic subjects may present a correct mastery of the formal aspects of speech, they have difficulties in prosody (music of speech), leading to communication disorders. Few behavioural studies have revealed a prosodic impairment in children with autism, and among the few fMRI studies aiming at assessing the neural network involved in language, none has specifically studied prosodic speech. The aim of the present study was to characterize specific prosodic components such as linguistic prosody (intonation, rhythm and emphasis) and emotional prosody and to correlate them with the neural network underlying them. Methodology/Principal Findings We used a behavioural test (Profiling Elements of the Prosodic System, PEPS) and fMRI to characterize prosodic deficits and investigate the neural network underlying prosodic processing. Results revealed the existence of a link between perceptive and productive prosodic deficits for some prosodic components (rhythm, emphasis and affect) in HFA and also revealed that the neural network involved in prosodic speech perception exhibits abnormal activation in the left SMG as compared to controls (activation positively correlated with intonation and emphasis) and an absence of deactivation patterns in regions involved in the default mode. Conclusions/Significance These prosodic impairments could not only result from activation patterns abnormalities but also from an inability to adequately use the strategy of the default network inhibition, both mechanisms that have to be considered for decreasing task performance in High Functioning Autism.

Phonetic and phonological errors in children with high functioning autism and Asperger syndrome

This study involved a qualitative analysis of speech errors in children with autism spectrum disorders (ASDs). Participants were 69 children aged 5–13 years; 30 had high functioning autism and 39 had Asperger syndrome. On a standardized test of articulation, the minority (12%) of participants presented with standard scores below the normal range, indicating a speech delay/disorder. Although all the other children had standard scores within the normal range, a sizeable proportion (33% of those with normal standard scores) presented with a small number of errors. Overall 41% of the group produced at least some speech errors. The speech of children with ASD was characterized by mainly developmental phonological processes (gliding, cluster reduction and final consonant deletion most frequently), but non-developmental error types (such as phoneme specific nasal emission and initial consonant deletion) were found both in children identified as performing below the normal range in the standardized speech test and in those who performed within the normal range. Non-developmental distortions occurred relatively frequently in the children with ASD and previous studies of adolescents and adults with ASDs shows similar errors, suggesting that they do not resolve over time. Whether or not speech disorders are related specifically to ASD, their presence adds an additional communication and social barrier and should be diagnosed and treated as early as possible in individual children.

Emotional recognition in autism spectrum conditions from voices and faces

The present study reports on a new vocal emotion recognition task and assesses whether people with autism spectrum conditions (ASC) perform differently from typically developed individuals on tests of emotional identification from both the face and the voice. The new test of vocal emotion contained trials in which the vocal emotion of the sentence were congruent, incongruent, or neutral with respect to the semantic content. We also included a condition in which there was no semantic content (an ‘mmm’ was uttered using an emotional tone). Performance was compared between 11 adults with ASC and 14 typically developed adults. Identification of emotion from sentences in which the vocal emotion and the meaning of sentence were congruent was similar in people with ASC and a typically developed comparison group. However, the comparison group was more accurate at identifying the emotion in the voice from incongruent and neutral trials, and also from trials with no semantic content. The results of the vocal emotion task were correlated with performance on a face emotion recognition task. In decoding emotion from spoken utterances, individuals with ASC relied more on verbal semantics than did typically developed individuals, presumably as a strategy to compensate for their difficulties in using prosodic cues to recognize emotions.

Assessing prosodic skills in five European languages: Cross-linguistic differences in typical and atypical populations

Following demand for a prosody assessment procedure, the test Profiling Elements of Prosody in Speech-Communication (PEPS-C), has been translated from English into Spanish, French, Flemish and Norwegian. This provides scope to examine receptive and expressive prosodic ability in Romance (Spanish and French) as well as Germanic (English and Flemish) languages, and includes the possibility of assessing these skills with regard to lexical tone (Norwegian). Cross-linguistic similarities and differences relevant to the translation are considered. Preliminary findings concerning 8-year-old neurotypical children speaking the five languages are reported. The appropriateness of investigating contrastive stress in Romance as well as Germanic languages is considered: results are reported for assessing this skill in Spanish and English speakers and suggest that in Spanish it is acquired much later than in English. We also examine the feasibility of assessing and comparing prosodic disorder in the five languages, using assessments of prosody in Spanish and English speakers with Williams syndrome as an example. We conclude that, with caveats, the original design of the UK test may indicate comparable stages of prosodic development in neurotypical children and is appropriate for the evaluation of prosodic skills for adults and children, both neurotypical and with impairment, in all five languages.

Temporal markers of prosodic boundaries in children's speech production

It is often thought that the ability to use prosodic features accurately is mastered in early childhood. However, research to date has produced conflicting evidence, notably about the development of children’s ability to mark prosodic boundaries. This paper investigates (i) whether, by the age of eight, children use temporal boundary features in their speech in a systematic way, and (ii) to what extent adult listeners are able to interpret their production accurately and unambiguously. The material consists of minimal pairs of utterances: one utterance includes a compound noun, in which there is no prosodic boundary after the first noun, e.g. ‘coffee-cake and tea’, while the other utterance includes simple nouns, separated by a prosodic boundary, e.g. ‘coffee, cake and tea’. Ten eight-year-old children took part, and their productions were rated by 23 adult listeners. Two phonetic exponents of prosodic boundaries were analysed: pause duration and phrase-final lengthening. The results suggest that, at the age of 8, there is considerable variability among children in their ability to mark phrase boundaries of the kind analysed in the experiment, with some children failing to differentiate between the members of the minimal pairs reliably. The differences between the children in their use of boundary features were reflected in the adults’ perceptual judgements. Both temporal cues to prosodic boundaries significantly affected the perceptual ratings, with pause being a more salient determinant of ratings than phrase-final lengthening.

The relationship between socio-economic status and lexical development.

The British Picture Vocabulary Scale, second edition (BPVS‐II), a measure of receptive vocabulary, is widely used by speech and language therapists and researchers into speech and language disorders, as an indicator of language delay, but it has frequently been suggested that receptive vocabulary may be more associated with socio‐economic status. Studies on this topic have produced conflicting results. This study reviews the literature and tests the hypothesis that receptive vocabulary is associated with socio‐economic status. The BPVS‐II was administered to 76 typically‐developing children aged 4 to 11, classified according to deprivation category, in Edinburgh, Scotland. The results showed no significant correlation between the two measures. Error patterns within the results are examined to discover why there should be discrepancy between them and the findings of other studies. The interaction between word frequency and the items used in the BPVS‐II is examined, and implications for the use of the BPVS‐II with all children of primary school age are discussed.