Meaningful Speech Research Articles

Corticobasal degeneration as cause of progressive non‐fluent aphasia: Clinical, radiological and pathological study of an autopsy case

A Japanese male developed gradual loss of spontaneous speech at age 60. Three years later meaningful speech had deteriorated to the point that it had become restricted to monotonous utterances. Neuropsychological examination at age 62 showed that he had severe non-fluent aphasia. A brain MRI demonstrated mild cortical atrophy with ischemic lesions in the cerebral white matter. He was diagnosed as having primary progressive aphasia. At age 63, he was admitted to the hospital to reevaluate the neurological condition. Neurologic examination showed severe non-fluent aphasia, hyperreflexia, snout and sucking reflexes. No alien hand was observed. He was able to walk, dress, wash himself and use chopsticks as well as name real objects. At age 65, 99Tc-hexamethylpropyleneamine oxime single photon emission computed tomography (HMPAO-SPECT) revealed diffuse cerebral hypoperfusion that was particularly prominent in the left frontal lobe. An MRI showed progressive cortical atrophy with the definite atrophy of the left paracentral gyrus. The hippocampal formation and putamen were also atrophic. He died of pneumonia at age 67. The brain weighed 810 g with atrophy of the frontal lobe, globus pallidus, enlargement of the lateral ventricles and depigmentation of the substantia nigra. Microscopic examination showed severe neuronal loss and gliosis in the cerebral cortex, globus pallidus interna and substantia nigra. Ballooned neurons were observed in the cerebral cortex. Gallyas-Braak method revealed numerous astrocytic plaques and argentophilic threads in the cerebrum. Clinical diagnosis of corticobasal degeneration sometimes is difficult in individuals with atypical clinical presentations. More exact clinical and radiological criteria may warrant a diagnosis of corticobasal degeneration.

The relationship of neuronal activity within the sensori-motor region of the subthalamic nucleus to speech

Microelectrode recordings of human sensori-motor subthalamic neuronal activity during spoken sentence and syllable-repetition tasks provided an opportunity to evaluate the relationship between changes in neuronal activities and specific aspects of these vocal behaviors. Observed patterns of neuronal activity included a build up of activity in anticipation of the start of the utterance, a marked reduction in activity associated with the start of the utterance, and a burst of activity during the course of the sentence between the noun phrase and the verb phrase. Overall, changes of neuronal activity were more robust for the sentence repetition task. These data suggest that the basal ganglia play a role in generating meaningful speech utterances, which may parallel its role in complex sequential limb movements. It is possible that the basal ganglia play a role in generating the syntactical structure of language.

Aicardi syndrome: A report of five Indian cases

Five Indian cases of Aicardi syndrome, aged 1-13 years and all with the classic triad of infantile spasm, corpus callosal agenesis and chorioretinal lacunae, were presented. The purpose of this report was to demonstrate the clinical, electroencephalographic (EEG) and radiological spectrum and the treatment outcome of this disorder among the Indians. None of the patient had any family history of similar illness. All had profound psychomotor impairment with no meaningful speech development. There were microphthalmia in 2, optic disc coloboma in 1, interhemispheric cyst in 1, periventricular heterotopia in 2 and thoracolumbar kyphoscoliosis in 2 cases. They all had early onset epilepsy and there were multiple types of seizures. Two cases (40%) had the characteristic dissociated burst-suppression pattern in EEG. Two cases whose antiepileptic medications included vigabatrin had complete control of seizure.

Time Course of Top-down and Bottom-up Influences on Syllable Processing in the Auditory Cortex

In speech perception, extraction of meaning from complex streams of sounds is surprisingly fast and efficient. By tracking the neural time course of syllable processing with magnetoencephalography we show that this continuous construction of meaning-based representations is aided by both top-down (context-based) expectations and bottom-up (acoustic-phonetic) cues in the speech signal. Syllables elicited a sustained response at 200-600 ms (N400m) which became most similar to that evoked by words when the expectation for meaningful speech was increased by presenting the syllables among words and sentences or using sentence-initial syllables. This word-like cortical processing of meaningless syllables emerged at the build-up of the N400m response, 200-300 ms after speech onset, during the transition from perceptual to lexical-semantic analysis. These findings show that the efficiency of meaning-based analysis of speech is subserved by a cortical system finely tuned to lexically relevant acoustic-phonetic and contextual cues.

Selection of meaningless steady noise for masking of speech

This paper focuses on masking speech with meaningless steady noise as a way of realizing a comfortable sound environment. As a basis for research, meaningless steady noise at minimum sound pressure levels for masking of male or female meaningful speech is considered, based on psychological experiments using a method of adjustment. From the results, band-limited pink noise can be selected as the most effective noise for masking of speech. In the case of speech with a lower sound pressure level, the sound pressure level of the meaningless steady noise needs to be a little higher.

Speech perception in gated noise: The effects of spectral and temporal resolution and auditory streaming

Hearing-impaired (HI) listeners often report difficulty understanding speech in the presence of background noise, even in the presence of mild degrees of hearing loss. In addition, HI listeners show significantly less benefit from fluctuations in noise than do normal hearing (NH) listeners. Furthermore, HI listeners often show less accuracy of processing frequency and temporal information in acoustic signals and grouping them into a whole meaningful speech. The purpose of this study is to examine differences in performances of NH and HI listeners for speech perception in various types of noise. Three hypotheses will be examined in this study. First, the amount of masking release in HI listeners with mild hearing loss will be smaller than in NH listeners even when speech and noise are presented at intensities sufficient to overcome the hearing loss. Masking release will be measured for consonant recognition and sentence recognition by subtracting the percent correct in steady noise from that in gated noise. Second, the performance of HI listeners on spectral resolution, temporal resolution, and auditory streaming tasks will be significantly poorer than that of NH listeners. Third, the performance differences in these tasks may account for differences in masking release.

Perception of emotions from faces and voices following unilateral brain damage

The importance of the right hemisphere in emotion perception in general has been well documented but its precise role is disputed. We compared the performance of 30 right hemisphere damaged (RHD) patients, 30 left hemisphere damaged (LHD) patients, and 50 healthy controls on both facial and vocal affect perception tasks of specific emotions. Brain damaged subjects had a single episode cerebrovascular accident localised to one hemisphere. The results showed that right hemisphere patients were markedly impaired relative to left hemisphere and healthy controls on test performance: labelling and recognition of facial expressions and recognition of emotions conveyed by prosody. This pertained at the level of individual basic emotions, positive versus negative, and emotional expressions in general. The impairment remained highly significant despite covarying for the group’s poorer accuracy on a neutral facial perception test and identification of neutral vocal expressions. The LHD group were only impaired relative to controls on facial emotion tasks when their performance was summed over all the emotion categories and before age and other cognitive factors were taken into account. However, on the prosody test the LHD patients showed significant impairment, performing mid-way between the right hemisphere patients and healthy comparison group. Recognition of positive emotional expressions was better than negative in all subjects, and was not relatively poorer in the LHD patients. Recognition of individual emotions in one modality correlated weakly with recognition in another, in all three groups. These data confirm the primacy of the right hemisphere in processing all emotional expressions across modalities—both positive and negative—but suggest that left hemisphere emotion processing is modality specific. It is possible that the left hemisphere has a particular role in the perception of emotion conveyed through meaningful speech.

Hearing screening.

Hearing screening.

Distraction by competing speech in young and older adult listeners.

In 2 experiments, young and older adults heard target speech presented in quiet or with a competing speaker in the background. The distractor consisted either of meaningful speech or nonmeaningful speech composed of randomly ordered word strings (Experiment 1) or speech in an unfamiliar language (Experiment 2). Tests of recall for the target speech showed that older adults, but not younger adults, were impaired more by meaningful distractors than by nonmeaningful distracters. However, on a surprise recognition test, young adults were more likely than older adults to recognize meaningful distractor items. These results suggest that reduced efficiency in attentional control is an important factor in older adults' difficulty in recalling target speech in the presence of a background of competing speech.

Mind and brain in Rett disorder

Development and retention of speech is reported in 265 people with Rett syndrome: 30% (80) never gained real words, 55% (145) gained real words and lost them, 15%(40) retained some words and 6% of the total (16/265) continued to use phrases appropriately. Morphological studies of the cytoarchitecture of the speech areas in 14 cases indicate the existence of interhemispheric differences which form part of the infrastructure for speech processing. Ten adults with Rett syndrome and with meaningful speech are compared to age matched adults without speech. The profile of mind and strategies for coping with its problems are described by a family. Although the range in severity is wide the mental profile is remarkably consistent across the severity range with regard to both positive and negative aspects.

Down syndrome phonology: developmental patterns and intervention strategies.

This paper describes phonological development in children with Down syndrome paying particular attention to underlying deficits and intervention strategies. The first section provides an overview of factors believed to influence phonological development in this population. The second section describes four aspects of Down syndrome phonology: (1) the prelinguistic stage; (2) the transition to speech; (3) the phonology of the single words; and (4) phonological characteristics of conversational speech with a focus on intelligibility. Intervention strategies associated with each aspect are also presented. Children with Down syndrome are slow to acquire the phonological system of their mother tongue. In spite of normal or nearly normal prelinguistic development, these children are delayed in the use of meaningful speech and slow to acquire a productive vocabulary. In some cases their speech remains unintelligible throughout childhood and adolescence, making it difficult to communicate with those around them. The purpose of this paper is to summarize research on phonological development of children with Down syndrome with attention to underlying deficits and to the speech characteristics of prelinguistic vocalisations as well as words and conversation. Current views on intervention are also described.

Stutter-free and stutter-filled speech signals and their role in stuttering amelioration for English speaking adults

This study examined the power of an exogenously generated stuttered speech signal on stuttering frequency when compared to an exogenously generated normal speech signal. In addition, we examined the specific components of the second speech signal, which might be responsible for the inducement of fluency in people who stutter. Eight males and two females who stuttered participated in this study. Experiment I involved meaningful speech: normal continuous speech, normal interrupted speech, stuttered continuous speech, and stuttered interrupted speech, whereas Experiment II involved vowels and consonants: /a/, /a-i-u/, /s/, /s-sh-f/. The results indicated that stuttered and normal speech signals were equally effective in reducing stuttering frequency. Further, the vowels were more powerful than consonants in inducing fluency for people who stutter. It is suggested that acoustic manifestations of stuttering, rather than a problem, may be a natural compensatory mechanism to bypass or inhibit the ‘involuntary block’ at the neural level.

Disruption of comprehension by the meaning of irrelevant sound

This study investigates the claim that the disruption of comprehension by irrelevant sound is qualitatively different from that of short-term memory for order. Both meaningful and meaningless speech disrupted the comprehensive aspect of the task, but the effect of meaningful speech was significantly greater. Both rehearsal and semantic processing, which are involved in reading comprehension, seem to be susceptible to disruption by irrelevant meaningful speech. The study provides some evidence to suggest that the presence of meaning in the irrelevant sound in creases disruption of performance in cognitive tasks that also call upon processing of meaning.

The feasibility of a kinematic measure of lip closure during meaningful speech

Purpose : Assessment of dysarthria has traditionally been based on perceptual methods. The purpose of this study was to examine the feasibility of using 2D kinematic analysis to measure lip closure during normal speech. Method : Retroflective markers (4 mm diameter) were placed on the midline of each lip of three healthy male, caucasian volunteers aged 69 years who repeated the sentence 'My mother made me an apple and blackberry pie' six times. Videorecordings were analysed using the Ariel Performance Analysis System to calculate the distance between the lips before, during and after the sentence. Results : The graphs produced from the data objectively measured the distance between the lips and identified the eight bilabial sounds. However, in spite of stringent study criteria to minimize differences linked to age, gender and race, differences were found between participants. Conclusion : Kinematic 2D analysis may have potential for the objective measurement of lip closure in dysarthria in the context of meaningful speech. These results justify further pilot work to explore: the possible variability within defined populations; and the usefulness of 2D kinematic analysis in the measurement of disordered lip closure in dysarthria.

Babbling of an Infant with a Repaired Cleft Lip: A Case Study

The infant born with a cleft lip is faced with risk factors that threaten the development of speech-language skills. The earlier the age of identification and management of the developmental delay, the better the outcome. The attainment of the mature syllable is considered to be a critical measure of babbling competency. This single case study aimed to determine whether the formedness of the syllable in babbling would be affected by the cleft lip repaired prior to the onset of meaningful speech. Three samples of babbling in a naturalistic environment were video-recorded. Data was analysed following the principles of infraphonology, employing a perceptually-based method. A profile of infraphonological features was obtained. Results showed that the development of the mature syllable was attained. The results support the theories that babbling is a robust phenomenon. Clinical and research implications are discussed.

Late onset canonical babbling: a possible early marker of abnormal development.

By their 10th month of life, typically developing infants produce canonical babbling, which includes the well-formed syllables required for meaningful speech. Research suggests that emerging speech or language-related disorders might be associated with late onset of canonical babbling. Onset of canonical babbling was investigated for 1,536 high-risk infants, at about 10-months corrected age. Parental report by open-ended questionnaire was found to be an efficient method for ascertaining babbling status. Although delays were infrequent, they were often associated with genetic, neurological, anatomical, and/or physiological abnormalities. Over half the cases of late canonical babbling were not, at the time they were discovered associated with prior significant medical diagnoses. Late canonical-babbling onset may be a predictor of later developmental disabilities, including problems in speech, language, and reading.

"So That We May Speak of Them": Enjoying the Middle Ages

This essay explores the significance of enjoyment to medieval studies, and to some of the discontents of contemporary literary and cultural studies more generally.1 What, to begin with, is the nature of the signifying field in which medievalist historiography, as a mode of sublimation, takes place? I use the term sublimation to refer to the problem addressed by Freud of how the creation of art and other forms of cultural achievement may be understood in relation to desire.2 The movie Babe will help us to an initial sketch of what is at stake in the relation of the signifier to desire and memory. Babe is, first of all, a film with a recognizably medievalist agenda. It celebrates love between master and servant (these days, animals have to stand in for the peasants), and rural life as the scene in which such love might be rediscovered. It expresses distaste for technology, focused especially on communications in the form of a Fax machine, but also recuperates the Fax, as well as discipline, training, technique. These figures recall the master tropes of anti-utilitarian medievalism in the nineteenth century.3 So does the film's insistent association of meaning less speech with commercialism and disbelief in the remarkable, and its association of meaningful speech with Babe's taciturn but loving farmer? a man behind the times who nonetheless is able to succeed because he

Phonological development in Down syndrome

This article provides an overview of the literature on phonological development in infants and children with Down syndrome. The review is divided into four major sections: the first summarizes studies of factors that may impede normal phonological development in this population: hearing loss and abnormalities of the middle ear; anatomical and physiological features of the speech mechanism; characteristics of input; and perceptual and encoding abilities. The second section examines prelinguistic vocal development and the links between babble and speech. The third section reviews literature on phonological acquisition after the onset of meaningful speech and briefly summarizes research on speech intelligibility in Down syndrome individuals. The fourth section discusses recommendations for intervention programs aimed at improving articulation and phonology in children with Down syndrome. MRDD Research Reviews 1997;3:300–306. © 1997 Wiley-Liss, Inc.

Irrelevant speech and irrelevant tones: The relative importance of speech to the irrelevant speech effect.

Irrelevant auditory stimuli disrupt immediate serial recall. In the equipotentiality hypothesis, D. M. Jones and W. J. Macken (1993) made the controversial prediction that speech and tones have an equivalent disruptive effect. In the present study, 5 experiments tested their hypothesis. Experiments 1-4 showed that meaningful speech disrupts recall more than do tones. Experiments 3 and 4 provided some evidence that meaningful speech disrupts recall more than does meaningless speech, and Experiment 4 showed that even meaningless speech disrupts recall more than do tones. Using slightly different experimental procedures, Experiment 5 showed that letters disrupt recall more than do tones. Implications of these results for a number of theories of primary memory and the irrelevant speech effect are discussed.

The case of total deafness II: Phrasing in the prelinguistic vocalizations of a child with congenital absence of cochleas

ABSTRACTRecent work has suggested that phrasing occurs in prelinguistic vocalizations, and that audition significantly influences prelinguistic vocal development. The present report is about the continuing study of a child who is referred to as congenitally acochlear because he was born with complete bilateral absence of cochleas. The only prior report on the vocal development of an acochlear child was provided in a previous article in this journal about the present subject (Lynch, Oiler, & Steffens, 1989). Because this child was not producing meaningful speech during the 27 to 42 months of age in which he was studied, investigation of him provided a unique opportunity to observe prelinguistic vocal development in the complete absence of auditory information. In the prior study of the acochlear child, the analytical focus was on developmental changes in relations between his syllable characteristics and those of mature speech. In the present study, the analytical focus was on a recently introduced approach to the study of prelinguistic vocalizations involving the description of syllable groupings within a prosodic hierarchy. Adult judges identified a hierarchy of syllables embedded within utterances and utterances embedded within prelinguistic phrases in the acochlear child's vocalizations. Similar to the prelinguistic phrases of typically developing infants and infants with Down syndrome previously reported on (Lynch, Oller, Steffens, & Buder, 1995), the present child's prelinguistic phrases were characterized by a systematic lengthening of phrase-final syllables and cohesive temporal patterning. In addition, the durations of the acochlear child's prelinguistic phrases were similar to those of typically developing infants. However, in contrast with those of typically developing infants and infants with Down syndrome, the durational features of the prelinguistic phrases of the acochlear child were relatively unstable across development. Overall, the results indicate that audition is not necessary for the formation of prelinguistic phrasing, but hearing does influence certain aspects of prelinguistic phrasing. Based on the data obtained on this subject, typically developing infants, and infants with Down syndrome, essential characteristics of well-formed prelinguistic phrases are proposed. These are termed “canonical” phrases; their production and development may be important in the acquisition of meaningful speech.