The role of multimodal cues in second language comprehension.

In face-to-face communication, multimodal cues such as prosody, gestures, and mouth movements can play a crucial role in language processing. While several studies have addressed how these cues contribute to native (L1) language processing, their impact on non-native (L2) comprehension is largely unknown. Comprehension of naturalistic language by L2 comprehenders may be supported by the presence of (at least some) multimodal cues, as these provide correlated and convergent information that may aid linguistic processing. However, it is also the case that multimodal cues may be less used by L2 comprehenders because linguistic processing is more demanding than for L1 comprehenders, leaving more limited resources for the processing of multimodal cues. In this study, we investigated how L2 comprehenders use multimodal cues in naturalistic stimuli (while participants watched videos of a speaker), as measured by electrophysiological responses (N400) to words, and whether there are differences between L1 and L2 comprehenders. We found that prosody, gestures, and informative mouth movements each reduced the N400 in L2, indexing easier comprehension. Nevertheless, L2 participants showed weaker effects for each cue compared to L1 comprehenders, with the exception of meaningful gestures and informative mouth movements. These results show that L2 comprehenders focus on specific multimodal cues - meaningful gestures that support meaningful interpretation and mouth movements that enhance the acoustic signal - while using multimodal cues to a lesser extent than L1 comprehenders overall.

Mismatch Responses to Speech Contrasts in Preschoolers with and without Developmental Language Disorder.

This study compared cortical responses to speech in preschoolers with typical language development (TLD) and with Developmental Language Disorder (DLD). We investigated whether top-down language effects modulate speech perception in young children in an adult-like manner. We compared cortical mismatch responses (MMRs) during the passive perception of speech contrasts in three groups of participants: preschoolers with TLD (n = 11), preschoolers with DLD (n = 16), and adults (n = 20). We also measured children's phonological skills and investigated whether they are associated with the cortical discrimination of phonemic changes involving different linguistic complexities. The results indicated top-down language effects in adults, with enhanced cortical discrimination of lexical stimuli but not of non-words. In preschoolers, the TLD and DLD groups did not differ in the MMR measures, and no top-down effects were detected. Moreover, we found no association between MMRs and phonological skills, even though the DLD group's phonological skills were significantly lower. Our findings suggest that top-down language modulations in speech discrimination may not be present during early childhood, and that children with DLD may not exhibit cortical speech perception deficits. The lack of association between phonological and MMR measures indicates that further research is needed to understand the link between language skills and cortical activity in preschoolers.

The Impact of Maxillary Osteotomy on Fricatives in Cleft Lip and Palate: A Perceptual Speech and Acoustic Study.

INTRODUCTION: Abnormal facial growth is a recognized outcome in cleft lip and palate (CLP), resulting in a concave profile and a class III occlusal status. Maxillary osteotomy (MO) is undertaken to correct this facial deformity, and the surgery can impact speech articulation, although the evidence remains limited and ill-defined for the CLP population. AIMS: The aim of the study was to investigate the impact of MO on the production of the fricatives /f/ and /s/, using perceptual and acoustic analyses, and to explore the nature of speech changes. METHODS: Twenty participants with CLP were seen 0-3 months pre-operatively (T1) and 3 months (T2) and 12 months (T3) after MO. A normal group (N = 20) was similarly recruited. Perceptual speech data was collected according to a validated framework and ratings made on audio and audio-video recordings (VIDRat). Spectral moments were centre of gravity (CG), standard deviation (SD), skewness (SK) and kurtosis (KU). Reliability studies were carried out for all speech analyses. RESULTS: For the CLP group, VIDRat identified dentalization/interdentalization as the main type of pre-operative error for /s/ with a statistically significant improvement over time, χ2(2) = 6.889, p = 0.032. Effect sizes were medium between T1 and T3 (d = 0.631) and small between T2 and T3 (d = 0.194). For the acoustic data, effect sizes were similarly medium between T1 and T2 (e.g., SK, /f/ d = 0.579, /s/ d = 0.642) and small between T1 and T3 across all acoustic parameters. Independent t tests showed mainly statistically significant differences between both groups at all time points with large effect sizes (e.g., T2 CG, t = -4.571, p < 0.001, d =1.581), indicating that /s/ was not normalized post-operatively. For /f/, differences tended to be at T1 with large effect sizes (e.g., CG, t = -2.307, p = 0.028, d = 0.797), reflecting normalization. CONCLUSIONS AND IMPLICATIONS: This is the first speech acoustic study on /f/ for individuals with CLP undergoing MO. The surgery has a positive impact on /f/ and /s/, which appear to stabilize 3 months post-operatively. Speech changes are an automatic and a direct consequence of the physical changes brought about by MO, effecting articulatory re-organization. The results of the study have direct clinical implications for the clinical care pathway for patients with CLP undergoing MO.

Trait anxiety effects on late phase threatening speech processing: Evidence from electroencephalography.

The effects of threatening stimuli, including threatening language, on trait anxiety have been widely studied. However, whether anxiety levels have a direct effect on language processing has not been so consistently explored. The present study focuses on event-related potential (ERP) patterns resulting from electroencephalographic (EEG) measurement of participants' (n = 36) brain activity while they perform a dichotic listening task. Participants' anxiety level was measured via a behavioural inhibition system scale (BIS). Later, participants listened to dichotically paired sentences, one neutral and the other threatening, and indicated at which ear they heard the threatening stimulus. Threatening sentences expressed threat semantically-only, prosodically-only, or both combined (congruent threat). ERPs showed a late positivity, interpreted as a late positive complex (LPC). Results from Bayesian hierarchical models provided strong support for an association between LPC and BIS score. This was interpreted as an effect of trait anxiety on deliberation processes. We discuss two possible interpretations. On the one hand, verbal repetitive thinking, as associated with anxious rumination and worry, can be the mechanism disrupting late phase deliberation processes. Instantiated by inner speech, verbal repetitive thinking might be the vehicle of anxiety-related reappraisal and/or rehearsal. On the other hand, increased BIS could be simply affecting an extended evaluation stage as proposed by multistep models, maybe due to over-engagement with threat or to task-related effects.

More than words: word predictability, prosody, gesture and mouth movements in natural language comprehension.

The ecology of human language is face-to-face interaction, comprising cues such as prosody, co-speech gestures and mouth movements. Yet, the multimodal context is usually stripped away in experiments as dominant paradigms focus on linguistic processing only. In two studies we presented video-clips of an actress producing naturalistic passages to participants while recording their electroencephalogram. We quantified multimodal cues (prosody, gestures, mouth movements) and measured their effect on a well-established electroencephalographic marker of processing load in comprehension (N400). We found that brain responses to words were affected by informativeness of co-occurring multimodal cues, indicating that comprehension relies on linguistic and non-linguistic cues. Moreover, they were affected by interactions between the multimodal cues, indicating that the impact of each cue dynamically changes based on the informativeness of other cues. Thus, results show that multimodal cues are integral to comprehension, hence, our theories must move beyond the limited focus on speech and linguistic processing.

A perceptual outcome measure of velopharyngeal function based on the Cleft Audit Protocol for Speech-Augmented (CAPS-A VPC-Sum): Validation through a speech osteotomy study.

BACKGROUND: The status of the velopharyngeal mechanism can be inferred from perceptual ratings of specified speech parameters. Several studies have proposed the measure of an overall velopharyngeal composite score based on these perceptual ratings and have reported good validity. The Cleft Audit Protocol for Speech-Augmented (CAPS-A) is a validated and reliable perceptual framework for the assessment of cleft speech and velopharyngeal function used by all Regional Cleft Services in the UK and Ireland. An overall velopharyngeal composite summary score based on the CAPS-A would serve as an important surgical outcome measure of speech. AIMS: To develop and validate a velopharyngeal composite summary score based on perceptual ratings made on the CAPS-A (CAPS-A VPC-Sum) using data from a maxillary osteotomy (MO) study. METHODS & PROCEDURES: There were two surgical groups: a cleft lip and palate (CLP) (N = 20) group and a non-CLP group (N = 10), and a normal control group (N = 20). Participants in groups 1 and 2 were seen for perceptual and instrumental assessments of speech and velopharyngeal function preoperatively (T1), 3 months (T2) and 12 months (T3) postoperatively. Perceptual speech data were collected and rated by independent listeners using CAPS-A. OUTCOMES & RESULTS: Moderate to strong interrater reliability for perceptual data (rs = 0.503-1.000, all p < 0.01) and strong to very strong reliability for videofluoroscopic measurements (rs = 0.746-0.947) were found. Construct validity of the CAPS-A VPC-Sum was shown by an increase in postoperative scores for the CLP group only Ï°2 (2) = 9.769, p = 0.008 and significant differences between the CLP and the other two groups at T2 and T3 using independent t-tests. Convergent and divergent validity was indicated by a positive moderate correlation with related parameters (e.g., hypernasality rs = 0.869, p < 0.01) and a weak correlation with unrelated parameters (e.g., amount of forward advancement rs = 0.160, p = 0.526). Criterion validity was found by a moderate correlation between closure ratio rs = -0.541, p = 0.020 and CAPS-A VPC-Sum. CONCLUSIONS & IMPLICATIONS: A velopharyngeal composite score based on perceptually rated parameters serves as an important surgical speech outcome measure. The CAPS-A VPC-Sum is a useful, reliable and valid outcome measure of velopharyngeal function. There are added positive implications for other clinicians using geographically and language-specific adapted versions of the CAPS-A internationally. WHAT THIS PAPER ADDS: What is already known on this subject Velopharyngeal composite scores based on perceptually rated speech parameters have been shown to have both clinical and research utility, serving as a useful surgical outcome measure. However, such a composite score must be specifically validated on the perceptual speech framework upon which it is based, as there are differences in measurement methods and terminology across cleft speech perceptual frameworks internationally. What this paper adds to existing knowledge The CAPS-A is a nationally used tool in the UK and Ireland for audit and research purposes with validated and adapted international versions. This paper reports on the validation of the derived velopharyngeal composite score measure based on the CAPS-A and an English-speaking sample, providing evidence of its validity through a speech osteotomy study. What are the potential or actual clinical implications of this work? This work provides CLP teams who use CAPS-A with a validated surgical speech outcome measure of velopharyngeal function. It has positive implications also for adapted versions of the CAPS-A internationally.

The Effect of Visual Perceptual Load on Auditory Awareness of Social vs. Non-social Stimuli in Individuals with Autism.

This study examined the effect of increasing visual perceptual load on auditory awareness for social and non-social stimuli in adolescents with autism spectrum disorder (ASD, n = 63) and typically developing (TD, n = 62) adolescents. Using an inattentional deafness paradigm, a socially meaningful ('Hi') or a non-social (neutral tone) critical stimulus (CS) was unexpectedly presented under high and low load. For the social CS both groups continued to show high awareness rates as load increased. Awareness rates for the non-social stimulus were reduced when load increased for the TD, but not the ASD group. The findings indicate enhanced capacity for non-social stimuli in ASD compared to TD, and a special attentional status for social stimuli in the TD group.

Semantic and prosodic threat processing in trait anxiety: is repetitive thinking influencing responses?

The present study attempts to identify how trait anxiety, measured as worry-level, affects the processing of threatening speech. Two experiments using dichotic listening tasks were implemented; where participants had to identify sentences that convey threat through three different information channels: prosody-only, semantic-only and both semantic and prosody (congruent threat). We expected different ear advantages (left or right) depending on task demands, information type, and worry level. We used a full Bayesian approach for statistical modelling and analysis. Main results indicate that as worry-level increases, participants' reaction times increase. We explain this effect by proposing a fourth stage, associated with goal-oriented deliberation, for a three-phasic multistep model of emotional language processing. Higher levels of trait anxiety could induce verbal repetitive thinking (i.e. worry and/or rumination), which might prolong the mentioned deliberation stages, thus slowing down responses.

Identifying Predictors of Acquired Velopharyngeal Insufficiency in Cleft Lip and Palate Following Maxillary Osteotomy Using Multiple Regression Analyses.

BACKGROUND: Maxillary osteotomy is typically undertaken to correct abnormal facial growth in cleft lip and palate. The surgery can cause velopharyngeal insufficiency resulting in hypernasality. This study aims to identify valid predictors of acquired velopharyngeal insufficiency following maxillary osteotomy by using a range of perceptual and instrumental speech investigations and multiple regression. METHODS: A prospective study was undertaken consisting of a consecutive series of patients with cleft lip and palate (N = 20) undergoing maxillary osteotomy by a single surgeon. Participants were seen at: 0 to 3 months pre-surgery (T1), 3-months (T2), and 12-months (T3) post-surgery. Hypernasality was rated using the cleft audit protocol for speech-augmented (CAPS-A) and visual analog scales, and nasalance was measured on the Nasometer II 6400. For lateral videofluorosopic and nasendoscopic images, visual perceptual ratings and quantitative ratiometric measurements were undertaken. Multiple regression analyses were undertaken to identify predictors. RESULTS: T3 models with hypernasality as the dependent variable were found to be a good fit and significant (eg, CAPS-A: R2 = 0.920, F(11,7) = 7.303, P = 0.007). Closure ratio (a quantitative ratiometric measurement) and proportion of palate contacting the posterior pharyngeal wall (a visual perceptual rating) were identified as significant predictors for the CAPS-A model (P = 0.030, P = 0.002).

Effect of Maxillary Osteotomy on Speech in Cleft Lip and Palate: Instrumental Outcomes of Velopharyngeal Function.

OBJECTIVE: To investigate the effect of maxillary osteotomy on velopharyngeal function in cleft lip and palate (CLP) using instrumental measures. DESIGN: A prospective study. PARTICIPANTS: A consecutive series of 20 patients with CLP undergoing maxillary osteotomy by a single surgeon were seen at 0 to 3 months presurgery (T1), 3 months (T2), and 12 months (T3) post-surgery. INTERVENTIONS: Nasalance was measured on the Nasometer II 6400. For videofluoroscopy and nasendoscopy data, visual perceptual ratings, for example, palatal lift angle (PLAn), and quantitative ratiometric measurements, for example, closure ratio (CRa), were made using a validated methodology and computer software. Reliability studies were undertaken for all instrumental measures. MAIN OUTCOME MEASURES: Repeated measures analysis of variance (with time at 3 levels) for nasalance and each velar parameter. Planned comparisons across pairs of time points (T1-T2, T1-T3, and T2-T3) including effect sizes. RESULTS: A significant difference over time was found for nasalance (P = .001) and planned comparisons across pairs of time points were significant between T1 and T2 (P = .008), T1 and T3 (P = .002), but not between T2 and T3 (P = .459) providing evidence that maxillary osteotomy can impact on nasalance adversely and that the changes seen are permanent and stable. There were also significant differences over time for PLAn (P = .012) and CRa (P = -.059) and planned comparisons for both velar parameters reflected similar findings to those of nasalance. CONCLUSIONS: Maxillary osteotomy can adversely affect velopharyngeal function in patients with CLP. The study provides evidence for a much earlier post-surgery review even as early as 3 months after surgery.

Dissociable effects of prediction and integration during language comprehension: evidence from a large-scale study using brain potentials.

Composing sentence meaning is easier for predictable words than for unpredictable words. Are predictable words genuinely predicted, or simply more plausible and therefore easier to integrate with sentence context? We addressed this persistent and fundamental question using data from a recent, large-scale (n = 334) replication study, by investigating the effects of word predictability and sentence plausibility on the N400, the brain's electrophysiological index of semantic processing. A spatio-temporally fine-grained mixed-effect multiple regression analysis revealed overlapping effects of predictability and plausibility on the N400, albeit with distinct spatio-temporal profiles. Our results challenge the view that the predictability-dependent N400 reflects the effects of either prediction or integration, and suggest that semantic facilitation of predictable words arises from a cascade of processes that activate and integrate word meaning with context into a sentence-level meaning. This article is part of the theme issue 'Towards mechanistic models of meaning composition'.

Emotional Connotations of Musical Instrument Timbre in Comparison With Emotional Speech Prosody: Evidence From Acoustics and Event-Related Potentials.

Music and speech both communicate emotional meanings in addition to their domain-specific contents. But it is not clear whether and how the two kinds of emotional meanings are linked. The present study is focused on exploring the emotional connotations of musical timbre of isolated instrument sounds through the perspective of emotional speech prosody. The stimuli were isolated instrument sounds and emotional speech prosody categorized by listeners into anger, happiness and sadness, respectively. We first analyzed the timbral features of the stimuli, which showed that relations between the three emotions were relatively consistent in those features for speech and music. The results further echo the size-code hypothesis in which different sound timbre indicates different body size projections. Then we conducted an ERP experiment using a priming paradigm with isolated instrument sounds as primes and emotional speech prosody as targets. The results showed that emotionally incongruent instrument-speech pairs triggered a larger N400 response than emotionally congruent pairs. Taken together, this is the first study to provide evidence that the timbre of simple and isolated musical instrument sounds can convey emotion in a way similar to emotional speech prosody.

Large-scale replication study reveals a limit on probabilistic prediction in language comprehension.

Do people routinely pre-activate the meaning and even the phonological form of upcoming words? The most acclaimed evidence for phonological prediction comes from a 2005 Nature Neuroscience publication by DeLong, Urbach and Kutas, who observed a graded modulation of electrical brain potentials (N400) to nouns and preceding articles by the probability that people use a word to continue the sentence fragment ('cloze'). In our direct replication study spanning 9 laboratories (N=334), pre-registered replication-analyses and exploratory Bayes factor analyses successfully replicated the noun-results but, crucially, not the article-results. Pre-registered single-trial analyses also yielded a statistically significant effect for the nouns but not the articles. Exploratory Bayesian single-trial analyses showed that the article-effect may be non-zero but is likely far smaller than originally reported and too small to observe without very large sample sizes. Our results do not support the view that readers routinely pre-activate the phonological form of predictable words.

Relationship between speech-evoked neural responses and perception of speech in noise in older adults.

Speech-in-noise (SPIN) perception involves neural encoding of temporal acoustic cues. Cues include temporal fine structure (TFS) and envelopes that modulate at syllable (Slow-rate ENV) and fundamental frequency (F0-rate ENV) rates. Here the relationship between speech-evoked neural responses to these cues and SPIN perception was investigated in older adults. Theta-band phase-locking values (PLVs) that reflect cortical sensitivity to Slow-rate ENV and peripheral/brainstem frequency-following responses phase-locked to F0-rate ENV (FFRENV_F0) and TFS (FFRTFS) were measured from scalp-electroencephalography responses to a repeated speech syllable in steady-state speech-shaped noise (SpN) and 16-speaker babble noise (BbN). The results showed that (1) SPIN performance and PLVs were significantly higher under SpN than BbN, implying differential cortical encoding may serve as the neural mechanism of SPIN performance that varies as a function of noise types; (2) PLVs and FFRTFS at resolved harmonics were significantly related to good SPIN performance, supporting the importance of phase-locked neural encoding of Slow-rate ENV and TFS of resolved harmonics during SPIN perception; (3) FFRENV_F0 was not associated to SPIN performance until audiometric threshold was controlled for, indicating that hearing loss should be carefully controlled when studying the role of neural encoding of F0-rate ENV. Implications are drawn with respect to fitting auditory prostheses.

Progressive dysarthria and augmentative and alternative communication in conversation: establishing the reliability of the Dysarthria-in-Interaction Profile.

BACKGROUND: The Dysarthria-in-Interaction Profile's potential contribution to the clinical assessment of dysarthria-in-conversation has been outlined in the literature, but its consistency of use across different users has yet to be reported. AIMS: To establish the level of consistency across raters on four different interaction categories. That is, how reliable clinicians are when rating a series of videos. A secondary aim was to investigate the relationship between raters' estimates of dysarthric speech intelligibility and their rating of each dyad's overall interaction. METHODS & PROCEDURES: Ten UK speech and language therapists rated independently a series of 40 video samples featuring people with progressive dysarthria in conversation with family members. An equal number of video samples was selected from a collection of recordings featuring four different types of interactional relationship. OUTCOMES & RESULTS: The results show that practising speech and language therapists can rate consistently, and with a high degree of agreement, a series of everyday conversation videos featuring dyads with progressive dysarthria and presenting at different interaction levels. The results also indicate that speech intelligibility does not predict the level of impairment in the interaction in a systematic way suggesting that conversation contains elements that are not directly related to speech intelligibility. CONCLUSIONS & IMPLICATIONS: Further work is required to establish the clinical functionality of this tool, but the results presented here support the development of this conversation profiling system, particularly for people experiencing significant intelligibility problems but remaining highly interactive/communicative.

Effects of Auditory Attention Training with the Dichotic Listening Task: Behavioural and Neurophysiological Evidence.

Facilitation of general cognitive capacities such as executive functions through training has stirred considerable research interest during the last decade. Recently we demonstrated that training of auditory attention with forced attention dichotic listening not only facilitated that performance but also generalized to an untrained attentional task. In the present study, 13 participants underwent a 4-week dichotic listening training programme with instructions to report syllables presented to the left ear (FL training group). Another group (n = 13) was trained using the non-forced instruction, asked to report whichever syllable they heard the best (NF training group). The study aimed to replicate our previous behavioural results, and to explore the neurophysiological correlates of training through event-related brain potentials (ERPs). We partially replicated our previous behavioural training effects, as the FL training group tended to show more allocation of auditory spatial attention to the left ear in a standard dichotic listening task. ERP measures showed diminished N1 and enhanced P2 responses to dichotic stimuli after training in both groups, interpreted as improvement in early perceptual processing of the stimuli. Additionally, enhanced anterior N2 amplitudes were found after training, with relatively larger changes in the FL training group in the forced-left condition, suggesting improved top-down control on the trained task. These results show that top-down cognitive training can modulate the left-right allocation of auditory spatial attention, accompanied by a change in an evoked brain potential related to cognitive control.

Ideophones in Japanese modulate the P2 and late positive complex responses.

Sound-symbolism, or the direct link between sound and meaning, is typologically and behaviorally attested across languages. However, neuroimaging research has mostly focused on artificial non-words or individual segments, which do not represent sound-symbolism in natural language. We used EEG to compare Japanese ideophones, which are phonologically distinctive sound-symbolic lexical words, and arbitrary adverbs during a sentence reading task. Ideophones elicit a larger visual P2 response than arbitrary adverbs, as well as a sustained late positive complex. Our results and previous literature suggest that the larger P2 may indicate the integration of sound and sensory information by association in response to the distinctive phonology of ideophones. The late positive complex may reflect the facilitated lexical retrieval of arbitrary words in comparison to ideophones. This account provides new evidence that ideophones exhibit similar cross-modal correspondences to those which have been proposed for non-words and individual sounds.

The effect of visual perceptual load on auditory awareness in autism spectrum disorder.

Recent work on visual selective attention has shown that individuals with Autism Spectrum Disorder (ASD) demonstrate an increased perceptual capacity. The current study examined whether increasing visual perceptual load also has less of an effect on auditory awareness in children with ASD. Participants performed either a high- or low load version of a line discrimination task. On a critical trial, an unexpected, task-irrelevant auditory stimulus was played concurrently with the visual stimulus. In contrast to typically developing (TD) children, children with ASD demonstrated similar detection rates across perceptual load conditions, and reported greater awareness than TD children in the high perceptual load condition. These findings suggest an increased perceptual capacity in children with ASD that operates across sensory modalities.

Effect of maxillary osteotomy on speech in cleft lip and palate: perceptual outcomes of velopharyngeal function.

BACKGROUND: Abnormal facial growth is a well-known sequelae of cleft lip and palate (CLP) resulting in maxillary retrusion and a class III malocclusion. In 10-50% of cases, surgical correction involving advancement of the maxilla typically by osteotomy methods is required and normally undertaken in adolescence when facial growth is complete. Current evidence for the impact of the surgery on velopharyngeal function is weak and mixed. AIMS: The first objective of the study was to investigate the nature of the effect of maxillary osteotomy on the perceptual outcomes of velopharyngeal function in CLP. The second objective was to establish if speech changes seen early at 3 months post-operation persisted for a year after/following surgery', when it is considered that the maxilla is relatively stable. METHODS & PROCEDURES: Twenty consecutive patients with CLP undergoing maxillary osteotomy by a single surgeon were seen pre-operatively (T1), 3 months (T2) and 12 months (T3) post-operation. A non-cleft control group (NonCLP) undergoing surgery was also recruited. Speech data were collected using the Cleft Audit Protocol for Speech-Augmented (CAPS-A). A velopharyngeal composite score-summary (VPC-SUM) was derived from specific CAPS-A-rated parameters. An external CAPS-A-trained therapist, blinded to the study, rated the randomized samples and inter-rater reliability was established. OUTCOMES & RESULTS: For the CLP group, hypernasality and nasal turbulence increased significantly post-operation. Planned comparisons were significant for T1-T2 only with a medium effect size. For hypernasality, the CLP group differed statistically from the NonCLP group at T2 and T3. For nasal turbulence, the CLP group differed statistically from the NonCLP group at T2. For VPC-SUM, there were statistically significant changes post-operatively between T1-T2 and T1-T3 only with medium effect sizes for the CLP group only. CONCLUSIONS & IMPLICATIONS: This study provides evidence that maxillary osteotomy affects patients with and without CLP differently. In patients with CLP, surgery may impact negatively on velopharyngeal function for speech and changes seen early on at 3 months post-operatively appear to persist at 12 months postoperatively. The findings in this study have implications for the speech care pathway of patients with CLP undergoing maxillary osteotomy in terms of assessment, review and management.

Effect of aging on stimulated salivary flow in adults.

The literature on the effect of age on saliva production, which has implications for health, quality of life, differential diagnosis, and case management, remains inconclusive. Physiological changes, motor and sensory, are frequently reported with increasing age. It was hypothesized that there would be a change in saliva production with older age. Whole stimulated saliva was collected by asking participants to chew gauze for 1 minute and then comparing the weight of saliva produced according to age and sex. Data were collected in activity centers for older adults, workplaces, universities, and participants' homes. Five hundred forty healthy individuals (aged 20-97) in three age groups (young = 20-30; middle-aged = 40-50; older ≥ 70) participated (90 men and 90 women in each group). A decrement in saliva production was identified for age in that the young and older participants and the middle-aged and older participants differed significantly from each other, but no difference was found between the young and middle-aged participants. The main effect of sex was not significant, nor was the interaction of age and sex. The results have implications for research and clinical work, including the differential diagnosis and subsequent management of salivary flow impairment due to age or underlying medical diagnosis or treatment. The assessment tool is easily administered and inexpensive and lends itself to use in many different clinical and research settings by different professionals.