Blog Archives

Functional near-infrared spectroscopy for the assessment of speech related tasks

Over the past years functional near-infrared spectroscopy (fNIRS) has substantially contributed to the understanding of language and its neural correlates. In contrast to other imaging techniques, fNIRS is well suited to study language function in healthy and psychiatric populations due to its cheap and easy application in a quiet and natural measurement setting. Its relative insensitivity for motion artifacts allows the use of overt speech tasks and the investigation of verbal conversation. The present review focuses on the numerous contributions of fNIRS to the field of language, its development, and related psychiatric disorders but also on its limitations and chances for the future.

from Brain and Language

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Intensity-Invariant Coding in the Auditory System

The auditory system faithfully represents sufficient details from sound sources such that downstream cognitive processes are capable of acting upon this information effectively even in the face of signal uncertainty, degradation or interference. This robust sound source representation leads to an invariance in perception vital for animals to interact effectively with their environment. Due to unique nonlinearities in the cochlea, sound representations early in the auditory system exhibit a large amount of variability as a function of stimulus intensity. In other words, changes in stimulus intensity, such as for sound sources at differing distances, create a unique challenge for the auditory system to encode sounds invariantly across the intensity dimension. This challenge and some strategies available to sensory systems to eliminate intensity as an encoding variable are discussed, with a special emphasis upon sound encoding.

from Neuroscience and Biobehavioral Reviews

Perception of Suprasegmental Speech Features via Bimodal Stimulation: Cochlear Implant on One Ear and Hearing Aid on the Other

Conclusions: This study found a significant bimodal advantage for perception of all suprasegmental features, most probably due to the better low-frequency acoustic hearing that is provided by the HA. Outcomes suggest that in cases of residual hearing in the contralateral ear to the implanted ear, HA use should be encouraged.

from the Journal of Speech, Language, and Hearing Research

Perceptual discrimination of Shona lexical tones and low-pass filtered speech by left and right hemisphere damaged patients

At least for the phonemic and lexical levels, brain damage to the dominant hemisphere results in lexical tone impairment for LHD patients, and cognitive load processing results in a subdued but good performance for RHD patients. The LH is therefore dominant for processing tone when it is lexically distinctive.

from Aphasiology

MOTOR PERFORMANCE AND HAPTIC PERCEPTION IN PRESCHOOL BOYS WITH SPECIFIC IMPAIRMENT OF EXPRESSIVE LANGUAGE

Conclusions:  Deviations in gross-motor performance and haptic perception are very common in children with minor to moderate expressive-SLI, being embodied especially in less muscle strength of lower extremities, poorer ball skills, balance and haptic object recognition.

from Acta Paediatrica

Effects of Reduced Saliva Production on Swallowing in Patients with Sjogren’s Syndrome

This study aimed to further characterize the nature of swallowing dysfunction in patients with Sjogren’s syndrome (SS). Subjects filled out a perception of swallow function form. Measures of stimulated salivary flow rate were also taken, and videofluoroscopic evaluation of swallowing was completed. The amount of saliva produced by patients with SS was significantly less than that produced by normal age-matched controls, and these patients perceived their swallowing to be impaired. Few statistically significant differences were found between the SS group and normal age-matched controls on temporal measures of swallowing, and 96% of swallows in the SS group were judged to be functional. There was no correlation between perception of swallowing and amount of saliva produced. No strong correlations were found between temporal measures of swallowing and salivary flow rate. Results indicated that patients with SS tend to perceive their swallowing to be worse than physiologic swallowing measures indicate. The decreased saliva production in these patients does not appear to be the cause of their perceived swallowing difficulty but may affect their sensory judgment of swallow function. Future studies will focus on how quality of saliva affects swallowing in these patients.

from Dysphagia

Effects of language comprehension on visual processing – MEG dissociates early perceptual and late N400 effects

We investigated whether and when information conveyed by spoken language impacts on the processing of visually presented objects. In contrast to traditional views, grounded-cognition posits direct links between language comprehension and perceptual processing. We used a magnetoencephalographic cross-modal priming paradigm to disentangle these views. In a sentence-picture verification task, pictures (e.g. of a flying duck) were paired with three sentence conditions: A feature-matching sentence about a duck in the air, a feature-mismatching sentence about a duck in a lake, and an unrelated sentence. Brain responses to pictures showed enhanced activity in the N400 time-window for the unrelated compared to both related conditions in the left temporal lobe. The M1 time-window revealed more activation for the feature-matching than for the other two conditions in the occipital cortex. These dissociable effects on early visual processing and semantic integration support models in which language comprehension engages two complementary systems, a perceptual and an abstract one.

from Brain and Language

Evolutionary Conservation and Neuronal Mechanisms of Auditory Perceptual Restoration

Auditory perceptual ‘restoration’ occurs when the auditory system restores an occluded or masked sound of interest. Behavioral work on auditory restoration in humans began over 50 years ago using it to model a noisy environmental scene with competing sounds. It has become clear that not only humans experience auditory restoration: restoration has been broadly conserved in many species. Behavioral studies in humans and animals provide a necessary foundation to link the insights being obtained from human EEG and fMRI to those from animal neurophysiology. The aggregate of data resulting with multiple approaches across species has begun to clarify the neuronal bases of auditory restoration. Different types of neural responses supporting restoration have been found, supportive of multiple mechanisms working within a species. Yet a general principle has emerged that responses correlated with restoration mimic the response that would have been given to the uninterrupted sound of interest. Using the same technology to study different species will help us to better harness animal models of ‘auditory scene analysis’ to clarify the conserved neural mechanisms shaping the perceptual organization of sound and to advance strategies to improve hearing in natural environmental settings.

from Hearing Research

Lexical and Affective Prosody in Children With High-Functioning Autism

Conclusions: Children with HFA were as capable as their TD peers in receptive tasks of lexical stress and affective prosody. Prosody productions were atypically long, despite accurate differentiation of lexical stress patterns. Future research should use larger samples and spontaneous versus elicited productions.

from the Journal of Speech, Language, and Hearing Research

Clinical effects of insular damage in humans

Multiple disturbances following lesions of the insula are reviewed in the present article, including those related to autonomic function; gustatory, olfactory, auditory, somatosensory, and multimodal perception, as well as body awareness; the emotion of disgust; mood and willed action, addiction behavior, and language. Given the multiple and varied nature of the impairments revealed by lesion studies, we suggest that the insula, as a multimodal area, has a major role as a convergence zone implicated in the coordination between internal and external information through emotional subjective awareness. Methodological issues are discussed with attention paid to lesion etiology, and lesions involving adjacent areas to the insular cortex.

from Brain Structure and Function

Listener Perception of the Effect of Abdominal Kinematic Directives on Respiratory Behavior in Female Classical Singing

Breath management training in classical singing is becoming increasingly physiologically focused, despite evidence that directives focusing on chest-wall kinematic (ribcage and abdominal) behavior effect minimal change in acoustical measures of singing. A direct and proportionate relationship between breathing behavior and vocal quality is important in singing training because singing teachers rely primarily on changes in sound quality to assess the efficacy of breath management modification. Pedagogical opinion is also strongly divided over whether the strategy of retarding the reduction in abdominal dimension during singing has a negative effect on vocal quality. This study investigated whether changes in abdominal kinematic strategy were perceptible and whether listeners preferred a particular strategy. Fourteen experienced singing teachers and vocal coaches assessed audio samples of five female classical singers whose respiratory kinematic patterns during singing had been recorded habitually and under two simple, dichotomous directives: Gradually drawing the abdomen inward and gradually expanding the abdomen, during each phrase. Listeners rated the singers on standard of singing and of breath management. Ratings analysis took into consideration changes in kinematic behavior under each directive determined from the respiratory recordings. Listener ratings for two singers were unaffected by directive. For three singers, ratings were lower when the directive opposed habitual kinematic behavior. The results did not support the pedagogical assumption of a direct and proportional link between respiratory behavior and standard of singing or that the abdomen-outward strategy was deleterious to vocal quality. The findings demonstrate the importance of considering habitual breathing behavior in both research and pedagogical contexts.

from the Journal of Voice

Crossmodal and incremental perception of audiovisual cues to emotional speech

In this article we report on two experiments about the perception of audiovisual cues to emotional speech. The article addresses two questions: (1) how do visual cues from a speaker’s face to emotion relate to auditory cues, and (2) what is the recognition speed for various facial cues to emotion? Both experiments reported below are based on tests with video clips of emotional utterances collected via a variant of the well-known Velten method. More specifically, we recorded speakers who displayed positive or negative emotions, which were congruent or incongruent with the (emotional) lexical content of the uttered sentence. In order to test this, we conducted two experiments.

The first experiment is a perception experiment in which Czech participants, who do not speak Dutch, rate the perceived emotional state of Dutch speakers in a bimodal (audiovisual) or a unimodal (audio- or vision-only) condition. It was found that incongruent emotional speech leads to significantly more extreme perceived emotion scores than congruent emotional speech, where the difference between congruent and incongruent emotional speech is larger for the negative than for the positive conditions. Interestingly, the largest overall differences between congruent and incongruent emotions were found for the audio-only condition, which suggests that posing an incongruent emotion has a particularly strong effect on the spoken realization of emotions.

from Language and Speech

The development of perceptual grouping biases in infancy: A Japanese-English cross-linguistic study

Perceptual grouping has traditionally been thought to be governed by innate, universal principles. However, recent work has found differences in Japanese and English speakers’ non-linguistic perceptual grouping, implicating language in non-linguistic perceptual processes (Iversen, Patel, & Ohgushi, 2008). Two experiments test Japanese- and English-learning infants of 5–6 and 7–8 months of age to explore the development of grouping preferences. At 5–6 months, neither the Japanese nor the English infants revealed any systematic perceptual biases. However, by 7–8 months, the same age as when linguistic phrasal grouping develops, infants developed non-linguistic grouping preferences consistent with their language’s structure (and the grouping biases found in adulthood). These results reveal an early difference in non-linguistic perception between infants growing up in different language environments. The possibility that infants’ linguistic phrasal grouping is bootstrapped by abstract perceptual principles is discussed.

from Cognition

Unintended imitation in nonword repetition

Verbal repetition is conventionally considered to require motor-reproduction of only the phonologically relevant content of a perceived linguistic stimulus, while imitation of incidental acoustic properties of the stimulus is not an explicit part of this task. Exemplar-based theories of speech processing, however, would predict that imitation beyond linguistic reproduction may occur in word repetition. Five experiments were conducted in which verbal audio-motor translations had to be performed under different conditions. Nonwords varying in phonemic content, in vocal pitch (F0), and in speaking style (schwa-syllable expression) were presented. We experimentally varied the factors response delay (repetition vs. shadowing), intention-to-repeat (repetition vs. pseudo-naming), and phonological load (repetition vs. transformation). The responses of ten healthy participants were examined for phonemic accuracy and for traces of para-phonological imitation. Two aphasic patients with phonological impairments were also included, to find out if lesions to left anterior or posterior perisylvian cortex interfere with imitation.

In the healthy participants, significant imitation of both F0 and phonetic style was observed, with markedly stronger effects for the latter. Strong imitation was also found in an aphasic patient with a lesion to left anterior perisylvian cortex, whereas almost no imitation occurred in a patient with a lesion to the posterior language area. The degree of unintended imitation was modulated by each of the three independent factors introduced here. The results are discussed on the background of cognitive and neurolinguistic theories of imitation.

from the Journal of Voice

Spasmodic dysphonia, perceptual and acoustic analysis: presenting new diagnostic tools

Abstract In this article, we investigate whether (1) the IINFVo (Impression, Intelligibility, Noise, Fluency and Voicing) perceptual rating scale and (2) the AMPEX (Auditory Model Based Pitch Extractor) acoustical analysis are suitable for evaluating adductor spasmodic dysphonia (AdSD). Voice recordings of 12 patients were analysed. The inter-rater and intra-rater consistency showed highly significant correlations for the IINFVo rating scale, with the exception of the parameter Noise. AMPEX reliably analyses vowels (correlation between PUVF (percentage of frames with unreliable F0/voicing 0.748), running speech (correlation between PVF (percentage of voiced frames)/voicing 0.699) and syllables. Correlations between IINFVo and AMPEX range from 0.608 to 0.818, except for noise. This study indicates that IINFVo and AMPEX could be robust and complementary assessment tools for the evaluation of AdSD. Both the tools provide us with the valuable information about voice quality, stability of F0 (fundamental frequency) and specific dimensions controlling the transitions between voiced and unvoiced segments.

from the European Archives of Oto-Rhino-Laryngologyl