Anja Kuschmann

Intonation in neurogenic foreign accent syndrome

UNLABELLED Foreign accent syndrome (FAS) is a motor speech disorder in which changes to segmental as well as suprasegmental aspects lead to the perception of a foreign accent in speech. This paper focuses on one suprasegmental aspect, namely that of intonation. It provides an in-depth analysis of the intonation system of four speakers with FAS with the aim of establishing the intonational changes that have taken place as well as their underlying origin. Using the autosegmental-metrical framework of intonational analysis, four different levels of intonation, i.e., inventory, distribution, realisation and function, were examined in short sentences. Results revealed that the speakers with FAS had the same structural inventory at their disposal as the control speakers, but that they differed from the latter in relation to the distribution, implementation and functional use of their inventory. The current results suggest that these intonational changes cannot be entirely attributed to an underlying intonation deficit but reflect secondary manifestations of physiological constraints affecting speech support systems and compensatory strategies. These findings have implications for the debate surrounding intonational deficits in FAS, advocating a reconsideration of current assumptions regarding the underlying nature of intonation impairment in FAS. LEARNING OUTCOMES The reader will be able to (1) explain the relevance of intonation in defining foreign accent syndrome; (2) describe the process of intonation analysis within the autosegmental-metrical (AM) framework; and (3) discuss the manifestation of intonation changes in FAS at the different levels of intonation and their potential underlying nature.

Phonological and phonetic marking of information status in Foreign Accent Syndrome

BACKGROUND Foreign Accent Syndrome (FAS) is a motor speech disorder in which a variety of segmental and suprasegmental errors lead to the perception of a new accent in speech. Whilst changes in intonation have been identified to contribute considerably to the perceived alteration in accent, research has rarely focused on how these changes impact on the pragmatic use of intonation. However, a greater understanding of the role of intonational changes in FAS and its impact on the functional use of intonation is fundamental to developing appropriate assessment and subsequently treatment strategies for FAS. AIMS This study investigated intonation patterns in speakers with FAS and matched control participants with regard to their ability to signal new and given information (information status) within sentences. A phonetic and phonological perspective was taken with the aim of identifying the characteristics that were compromised in FAS to convey this linguistic function. METHODS & PROCEDURES Four speakers with FAS and four control participants participated in the speech production experiment. The speech data were assessed perceptually, and examined in relation to the use of the phonetic parameters fundamental frequency (f0), intensity and duration as well as phonological categories, i.e. pitch accents and de-accentuation, using the autosegmental-metrical (AM) framework of intonational analysis. OUTCOMES & RESULTS Both speaker groups employed all three phonetic parameters to differentiate between new and given information. However, groups differed regarding the use of phonological markers, with speakers with FAS frequently placing pitch accents on given information instead of de-accenting these elements. According to the perceptual evaluation, three of the four speakers with FAS had problems signalling information status. CONCLUSIONS & IMPLICATIONS The fact that speakers with FAS marked information status similarly to control speakers at the phonetic level, but failed to do so using phonological categories highlights the importance of assessing phonetic as well as phonological features to gain detailed information about the functional use of intonation in FAS.

Phonological markers of sentence stress in ataxic dysarthria and their relationship to perceptual cues

UNLABELLED A wide range of literature is available on the features of ataxic dysarthria, investigating segmental and prosodic characteristics by acoustic and perceptual means. However, very few studies have been published that look closely at the relationship between the observed phonetic disturbances and their perceptual sequelae, particularly in the area of prosody. The aim of the current study was therefore to examine the stress production of eight individuals with ataxic dysarthria and matched healthy controls, and to relate the results of phonological and perceptual evaluations to phonetic performances to better understand the relationship between these three components for speech outcomes. Speakers performed a sentence stress task which was analysed phonologically in terms of inventory, distribution, implementation and function of pitch accentuation. These data were then evaluated in relation to previously published phonetic and perceptual results on the same speaker group by the authors. Results indicated that the speakers with ataxia used a wide range of pitch patterns, but pitch-accented a higher number of words, and produced shorter phrases. The increased number of pitch accents per phrase was furthermore reflected in a reduced percentage of de-accented words in post-focal position. Perceptual results established this pattern as the main cause for listener errors in identifying the intended stressed item in an utterance. In addition, the performances of two speakers are discussed in greater detail. Although they were unable to de-accent, they nevertheless marked stress appropriately through phonetic compensatory strategies. LEARNING OUTCOMES After reading this article the reader will be able to (1) explain the relevance of phonology and phonetics in the perception of stress production in ataxic dysarthria; (2) describe the different levels of intonational analysis; and (3) understand the observed intonation patterns in ataxic dysarthria as well as the compensatory mechanisms speakers may adopt to produce stress.

The role of speaking styles in assessing intonation in foreign accent syndrome

Abstract Purpose. This paper evaluates the role of different speaking styles in defining intonation patterns in speakers with foreign accent syndrome. The methodological investigation aimed at establishing to what extent scripted and unscripted speech influence the phonological realization of intonation in disordered speech. Method. Four individuals with foreign accent syndrome and four gender-, age- and original dialect-matched control speakers were asked to perform a series of scripted and unscripted speech tasks including short sentences, a reading passage, a picture description and a monologue task. The speech data were analysed within the autosegmental-metrical framework of intonational analysis in relation to inventory, distribution, realization and functional use of intonational elements. Result. Findings revealed that the unscripted speaking styles provided a more comprehensive picture of the inventory and distribution of intonation contours, whereas differences in the functional use were more prominently reflected in the scripted data sets, in particular the short sentences. Conclusion. The findings highlight that the type of speaking style influences how intonation patterns are realized in disordered as well as healthy speech. A combination of scripted as well as unscripted data is, thus, required to obtain a comprehensive picture of the intonation abilities of a speaker with foreign accent syndrome.

Intonation patterns in older children with cerebral palsy before and after speech intervention

Abstract Purpose: This paper examined the production of intonation patterns in children with developmental dysarthria associated with cerebral palsy (CP) prior to and after speech intervention focussing on respiration and phonation. The study further sought to establish whether intonation performance might be related to changes in speech intelligibility. Method: Intonation patterns were examined using connected speech samples of 15 older children with moderate to severe developmental dysarthria due to CP (9 females; age range: 11–18). Recordings were made prior to and after speech intervention based on a systems approach. Analyses are focussed on the use of intonation patterns, pitch accentuation and phrasing. Result: Group analyses showed a significant increase in the use of rising intonation patterns after intervention. There were also some indications that this increase might have been related to gains in speech intelligibility for some of the children. No changes were observed regarding pitch accentuation and phrasing following intervention. Conclusion: The findings highlight that changes can occur in the use of intonation patterns in children with dysarthria and CP following speech systems intervention. It is hypothesised that the emergence of the rising pattern in some of the children’s intonational inventories possibly reflected improved breath support and control of laryngeal muscles.

Rhythmic performance in hypokinetic dysarthria: relationship between reading, spontaneous speech and diadochokinetic tasks

Highlights • We investigated speech rhythm in people with Parkinson’s Disease (PwPD) and controls.• Even mildly affected PwPD differed from controls in their rhythmic performance.• PwPD showed less difference between reading and spontaneous speech.• Spontaneous speech highlighted more differences between speakers than reading.• DDK performance did not relate to rhythmic behaviour in connected speech.

Sentence stress in children with dysarthria and cerebral palsy

Abstract Purpose: This study aimed to advance our understanding of how children with dysarthria and cerebral palsy (CP) realise sentence stress acoustically, and how well listeners could identify the position of the stressed word within these utterances. Method: Seven children with CP and eight typically developing children participated in the experiment. Stress on target words in two sentence positions was elicited through a picture-based question–answer paradigm. Acoustic parameters of stress [duration, intensity and fundamental frequency (F0)] were measured and compared between stressed and unstressed target words. For the perception experiment, ten listeners were asked to determine the position of the stressed word in the children’s productions. Result: Acoustic measures showed that at group level the typically developing children used all three acoustic parameters to mark sentence stress, whereas the children with CP showed changes in duration only. Individual performance variations were evident in both groups. Perceptually, listeners were significantly better at identifying the stressed words in the utterances produced by the typically developing children than those of the children with CP. Conclusion: The results suggest that children with CP can manipulate temporal speech properties to mark stress. This ability to modulate acoustic–prosodic features could be harnessed in intervention to enhance children’s functional communication.

What does it take to stress a word? Digital manipulation of stress markers in ataxic dysarthria

BACKGROUND Stress production is important for effective communication, but this skill is frequently impaired in people with motor speech disorders. The literature reports successful treatment of these deficits in this population, thus highlighting the therapeutic potential of this area. However, no specific guidance is currently available to clinicians about whether any of the stress markers are more effective than others, to what degree they have to be manipulated, and whether strategies need to differ according to the underlying symptoms. AIMS In order to provide detailed information on how stress production problems can be addressed, the study investigated (1) the minimum amount of change in a single stress marker necessary to achieve significant improvement in stress target identification; and (2) whether stress can be signalled more effectively with a combination of stress markers. METHODS & PROCEDURES Data were sourced from a sentence stress task performed by 10 speakers with ataxic dysarthria and 10 healthy matched control participants. Fifteen utterances perceived as having incorrect stress patterns (no stress, all words stressed or inappropriate word stressed) were selected and digitally manipulated in a stepwise fashion based on typical speaker performance. Manipulations were performed on F0, intensity and duration, either in isolation or in combination with each other. In addition, pitch contours were modified for some utterances. A total of 50 naïve listeners scored which word they perceived as being stressed. OUTCOMES & RESULTS Results showed that increases in duration and intensity at levels smaller than produced by the control participants resulted in significant improvements in listener accuracy. The effectiveness of F0 increases depended on the underlying error pattern. Overall intensity showed the most stable effects. Modifications of the pitch contour also resulted in significant improvements, but not to the same degree as amplification. Integration of two or more stress markers did not result in better results than manipulation of individual stress markers, unless they were combined with pitch contour modifications. CONCLUSIONS & IMPLICATIONS The results highlight the potential for improvement of stress production in speakers with motor speech disorders. The fact that individual parameter manipulation is as effective as combining them will facilitate the therapeutic process considerably, as will the result that amplification at lower levels than seen in typical speakers is sufficient. The difference in results across utterance sets highlights the need to investigate the underlying error pattern in order to select the most effective compensatory strategy for clients.