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Purpose Earlier investigations based on word and sentence repetition tasks had revealed that the most prevalent metrical pattern in German (the trochee)-unlike the iambic pattern-facilitates articulation in patients with apraxia of speech (AOS; e.g., Aichert, Späth, & Ziegler, 2016), confirming that segmental and prosodic aspects of speech production interact. In this study, we investigated if articulation in apraxic speakers also benefits from auditory priming by speech with a regular rhythm. Furthermore, we asked if the advantage of regular speech rhythm, if present, is confined to impairments at the motor planning stage of speech production (i.e., AOS) or if it also applies to phonological encoding impairments. Method Twelve patients with AOS, 12 aphasic patients with postlexical phonological impairment (PI), and 36 neurologically healthy speakers were examined. A sequential synchronization paradigm based on a sentence completion task was conducted in conditions where we independently varied the metrical regularity of the prime sentence (regular vs. irregular prime sentence) and the metrical regularity of the target word (trochaic vs. iambic). Results Our data confirmed the facilitating effect of regular (trochaic) word stress on speech accuracy in patients with AOS (target effect). This effect could, for the first time, also be demonstrated in individuals with PI. Moreover, the study also revealed an influence of the metrical regularity of speech input in both patient groups (prime effect). Conclusions Patients with AOS and patients with PI exploited rhythmic cues in the speech of a model speaker for the initiation and the segmental realization of words. There seems to be a robust metrical influence on speech at both the phonological and the phonetic planning stages of speech production.

Vocal learning is an exclusively human trait among primates. However, songbirds demonstrate behavioral features resembling human speech learning. Two circuits have a preeminent role in this human behavior; namely, the corticostriatal and the cerebrocerebellar motor loops. While the striatal contribution can be traced back to the avian anterior forebrain pathway (AFP), the sensorimotor adaptation functions of the cerebellum appear to be human specific in acoustic communication. This review contributes to an ongoing discussion on how birdsong translates into human speech. While earlier approaches were focused on higher linguistic functions, we place the motor aspects of speaking at center stage. Genetic data are brought together with clinical and developmental evidence to outline the role of cerebrocerebellar and corticostriatal interactions in human speech., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Several factors are known to influence speech accuracy in patients with apraxia of speech (AOS), e.g., syllable structure or word length. However, the impact of word stress has largely been neglected so far. More generally, the role of prosodic information at the phonetic encoding stage of speech production often remains unconsidered in models of speech production. This study aimed to investigate the influence of word stress on error production in AOS. Two-syllabic words with stress on the first (trochees) vs. the second syllable (iambs) were compared in 14 patients with AOS, three of them exhibiting pure AOS, and in a control group of six normal speakers. The patients produced significantly more errors on iambic than on trochaic words. A most prominent metrical effect was obtained for segmental errors. Acoustic analyses of word durations revealed a disproportionate advantage of the trochaic meter in the patients relative to the healthy controls. The results indicate that German apraxic speakers are sensitive to metrical information. It is assumed that metrical patterns function as prosodic frames for articulation planning, and that the regular metrical pattern in German, the trochaic form, has a facilitating effect on word production in patients with AOS., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Globus pallidus internus deep brain stimulation (GPi-DBS) can be an effective treatment for primary dystonia. However, speech disorders have previously been reported as a common possible side effect of the treatment., Objectives: To study possible deterioration of speech after GPi-DBS and describe this in different dimensions., Methods: Speech was systematically evaluated in 15 patients with predominant torticollis and GPi-DBS. Each patient was tested twice within one day in two stimulation conditions: ON-DBS vs. OFF-DBS. Speech analyses comprised both function-oriented (perceptual scales, acoustic analyses) and communication-related measures (intelligibility, naturalness). A control sample of 15 healthy speakers underwent the same speech assessment., Results: On the group level, patients with dystonia showed mild but significant impairment on the overall dysarthria scale, the intelligibility score, and the naturalness ratings in both stimulation conditions (Mann-Whitney, P < .05). No stimulation-induced deterioration was found. A slight increase in articulation rate was measured in the ON condition. On the single-case level, effects of GPi-DBS on speech were heterogenous. In one patient we observed a deterioration of speech (dysarthria), in a second patient with a history of childhood stuttering we found an aggravation of dysfluency. Impressive benefits could be documented in another patient who also suffered from spasmodic dysphonia., Conclusions: The study provides evidence that speech impairment is not a necessary side-effect of GPi-DBS in primary dystonia. Both, recurring of stuttering and a worsening of dysarthria may be seen in individual patients. The positive effects of GPi-DBS on the symptoms of spasmodic dysphonia merits further research as DBS is not commonly applied in this population., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Patterns of dysarthria in spinocerebellar ataxias (SCAs) and their discriminative features still remain elusive. Here we aimed to compare dysarthria profiles of patients with (SCA3 and SCA6 vs. Friedreich ataxia (FRDA), focussing on three particularly vulnerable speech parameters (speaking rate, prosodic modulation, and intelligibility) in ataxic dysarthria as well as on a specific oral non-speech variable of ataxic impairment, i.e., the irregularity of oral motor diadochokinesis (DDK). 30 Patients with SCA3, SCA6, and FRDA, matched for group size (n = 10 each), disease severity, and disease duration produced various speech samples and DDK tasks. A discriminant analysis was used to differentiate speech and non-speech parameters between groups. Regularity of DDK was specifically impaired in SCA3, whereas impairments of speech parameters, i.e., rate and modulation were stronger affected in SCA6. Speech parameters are particularly vulnerable in SCA6, while non-speech oral motor features are notably impaired in SCA3.

The pathogenesis of essential tremor (ET) is still under debate. Several lines of evidence indicate that ET is associated with cerebellar dysfunction. The aim of the present study was to find corroborating evidence for this claim by investigating balance and speech impairments in patients with ET. In addition, the effect of deep brain stimulation (DBS) on balance and speech function was studied. A group of 25 ET patients including 18 with postural and/or simple kinetic tremor (ETpt) and seven ET patients with additional clinical signs of cerebellar dysfunction (ETc) was compared to 25 healthy controls. In addition, 12 ET patients with thalamic DBS participated in the study. Balance control was assessed during gait and stance including tandem gait performed on a treadmill as well as static and dynamic posturography. Motor speech control was analyzed through syllable repetition tasks. Signs of balance impairment were found in early stages and advanced stages of ET. During locomotion, ET patients exhibited an increased number of missteps and shortened stride length with tandem gait. ETc patients and, to a lesser extent, ETpt patients had increased postural instability in dynamic posturography conditions that are sensitive to vestibular or vestibulocerebellar dysfunction. ETc but not ETpt patients exhibited significantly increased syllable durations. DBS had no discernable effect on speech performance or balance control. We conclude that the deficits in balance as well as the subclinical signs of dysarthria in a subset of patients confirm and extend previous findings that ET is associated with an impairment of the cerebellum.

The aim of the present study was to examine cognitive functions in a group of chronic patients with focal cerebellar lesions. Both effects of localization (anterior vs. posterior lobe) and side (left vs. right cerebellar hemisphere) were of interest. Fourteen patients with infarctions within the territory of the posterior inferior cerebellar artery (PICA) and seven patients with infarctions within the territory of the superior cerebellar artery (SCA) participated. The affected lobules and nuclei were assessed based on 3D MR imaging. The right cerebellar hemisphere was affected in eight PICA and two SCA patients, the left hemisphere in six PICA and four SCA patients. One SCA patient revealed a bilateral lesion. In order to study possible lateralization of functions, subjects performed a language task as well as standard neglect and extinction tests. Moreover, two tests of executive functions were applied. There were no significant group differences apart from a verbal fluency task, in which all cerebellar patients - but especially those with right-sided lesions - were impaired. Voxel-based lesion-symptom mapping (VLSM) revealed that a lesion of the right hemispheric lobule Crus II was associated with impaired performance in the verbal fluency task. In sum, the results showed preserved cognitive abilities in chronic cerebellar patients apart from impairments of verbal fluency in patients with right-cerebellar lesions. The latter findings are in line with the assumption that the right posterolateral cerebellar hemisphere supports functions associated with verbal fluency.

The prosodic quality of speech comprises intonation, accent pattern, and rhythm. Among others, these dimensions contribute to the linguistic structure of an utterance and subserve emotional behaviour. Both cortical and subcortical dysfunctions can give rise to impaired speech prosody. The present paper reviews the clinical and linguistic features of the various dys- and aprosodic syndromes as well as their neuroanatomic substrates. 1. Sporadically, lesions of the left hemisphere present with dysprosody in terms of a "foreign accent". In most instances this syndrome seems to be due to apraxia of speech. 2. Some authors consider dysprosodic speech a characteristic feature of Broca's aphasia. The dysprosody of these patients predominantly reflects disturbed temporal organisation of speech utterances. Altered intonation contours, presumably, result from disordered sentence planning rather than from deficits of pitch processing. Wernicke aphasics may show increased variability of intonational patterns. 3. Impaired discrimination and identification of affective prosody has been observed in patients with temporoparietal lesion of the right hemisphere ("auditory affective agnosia"). With respect to linguistic prosody, controversial findings are reported on. Besides pitch extraction from acoustic signals the right hemisphere seems to provide categorical representations of emotional behaviour required for the "interpretation" of perceived intonation. 4. Damage to the right hemisphere can give rise to monotonous speech devoid of affective modulation ("motor aprosodia"). It is unsettled to which extent linguistic suprasegmental features are also distorted. The available data indicate an underlying dysfunction of basal ganglia loops and/or transcallosal projections. 5. Both Parkinson's and Huntington's disease may present with reduced prosodic modulation of speech. Probably, these deficits reflect disordered motor control of articulatory and phonatory functions. At least with respect to Parkinsonian patients perceptual and acoustic studies have so far failed to provide sufficient evidence of impaired prosodic planning.

The frequencies of the first two formants of three German vowels in word context were determined by a formant tracking routine for 8 male subjects with closed head trauma. A centralized formant pattern was found to characterize vowel articulation in traumatic dysarthria. Different degrees of severity could be assessed and the process of recovery was described by the parameter 'formant triangle area'. An interpretation in articulatory terms is given and the results are discussed in the light of articulatory models.

Articulatory anticipation of vowel gestures was assessed in an apraxic patient, a dysarthric patient, and three normal speakers. The technique of assessment included perceptual identification of gated speech stimuli. The speech material consisted of /getVte/ utterances with the target vowels /i/, /y/, and /u/. In the case of the apraxic patient the gated vowels were identified at a later instant relative to the preceding plosion burst than in the normal speakers. This result was interpreted as reflecting a delayed onset of coarticulatory gestures, in particular lip rounding. The identification rates for the dysarthric's vowels rather reflected the general reduction of this patient's vowel space.

Formant analysis of tense, high, German vowels was performed to the end of obtaining information about the role of insufficient lip rounding in distorted vowel production of 8 traumatic dysarthrics. A comparison was made between two allophones of /y/ in different consonantal contexts. Noticeable undershoot in lip rounding or protrusion proved to occur in a context of conflicting labial gestures. Where the articulatory realization of a CVC sequence required gross tongue movements, a lingual undershoot resulted as the prevailing deficit. No evidence for dyscoordinative defects was obtained from the results.

Disorders of speech are a common and sometimes even the first symptom of parkinsonism. The various features of parkinsonian speech disorder include repetitive phenomena, disturbances of respiration, dysphonia, and impairment of articulation. This review aims at summarizing the neurological, phoniatric, and phonetical data regarding symptomatology, pathophysiology, and therapy of parkinsonian dysarthrophonia.

The aim of the present study was to investigate the manifestations of mutism after surgery in children with cerebellar tumors. Speech impairment following cerebellar mutism in children was investigated based on standardized acoustic speech parameters and perceptual criteria. Mutistic and non–mutistic children after cerebellar surgery as well as orthopedic controls were tested pre–and postoperatively. Speech impairment was compared with the localization of cerebellar lesions (i. e. affected lobules and nuclei). Whereas both control groups showed no abnormalities in speech and behavior, the mutistic group could be divided into children with dysarthria in post mutistic phase and children with mainly behavioral disturbances. In the mutistic children involvement of dentate and fastigial nuclei tended to be more frequent and extended than in the nonmutistic cerebellar children. Cerebellar mutism is a complex phenomenon of at least two types. Dysarthric symptoms during resolution of mutism support the anarthria hypothesis, while mainly behavioral changes suggest an explanation independent from speech motor control. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study was to examine verb generation in a larger group of children and adolescents with acute focal lesions of the cerebellum. Nine children and adolescents with cerebellar tumours participated. Subjects were tested a few days after tumour surgery. For comparison, a subgroup was tested also 1 or 2 days before surgery. None of the children had received radiation or chemotherapy at or before the time of testing. Eleven age- and education-matched control subjects participated. Subjects had to generate verbs to blocked presentations of photographs of objects. As control condition, the objects had to be named. Furthermore, dysarthria was quantified by means of a sentence production and syllable repetition task. Detailed analysis of individual 3D-MR images revealed that lesions affected cerebellar hemispheres in all children and adolescents. The right cerebellar hemisphere was affected in four and the left hemisphere in five subjects. In the present study, naming and verb generation accuracy were preserved in the majority of subjects with cerebellar lesions. No significant signs of learning deficits were observed, as reduction of reaction times over blocks was not different compared to controls. There was a trend of children and adolescents with right-hemispheric lesions to perform worse compared to controls. In this group, however, significant signs of dysarthria were present. In sum, no significant signs of disordered verb generation were observed in children and adolescents with acute cerebellar lesions. Findings suggest that the role of the cerebellum in verb generation may be less pronounced than previously suggested. Findings need to be confirmed in a larger group of subjects with acute focal lesions. [Copyright &y& Elsevier]

The present study investigated dysarthric symptoms in children with cerebellar tumors. Ten children with cerebellar tumors and 10 orthopedic control children were tested prior and one week after surgery. Clinical dysarthric symptoms were quantified in spontaneous speech. Syllable durations were analyzed in syllable repetition and sentence production tasks. Localization of the cerebellar lesions were defined after manual transfer from individual 2D-MR images onto 3D images of a spatially normalized healthy brain. Cerebellar children showed few and mild clinical signs of dysarthria. No difference was present in the sentence production task compared to controls. In five cerebellar children, syllables were prolonged in the syllable repetition task after surgery. Syllable duration normalized in an additional four-week session in all but one case. The MR-analysis showed that superior paravermal cerebellar areas likely involved in dysarthria in adults (paravermal lobules HVI, Crus I) were not significantly affected. In children, speech impairments appear to be rare after cerebellar surgery because tumors most commonly affect posterior-inferior and medial parts of the cerebellum while critical cerebellar regions are likely spared. The results suggest a similar localization of speech functions in the cerebellum in children and adults. [ABSTRACT FROM AUTHOR]