Monthly Archives: August 2009
Style, indexicality, and the social meaning of tag questions1
This article illustrates how the notions of style and indexicality can illuminate understanding of the social meaning of a specific linguistic variable, the tag question. Drawing on conversational speech and ethnographic data from a community of high school girls in northwest England, it quantitatively and qualitatively examines the discourse, grammatical, and phonological design of tag questions in this community. Members of four social groups are shown to use tag questions to similar effect, as a means of conducing particular points of view. However, these groups also exhibit striking differences in the stylistic composition of tags, distinctions that indexically construct stances and personas, which may in turn come to represent group identity. These data suggest that the social meaning of tag questions can be best ascertained by examining their internal composition and by situating them in their broader discursive and social stylistic contexts. (Adolescents, ethnography, indexicality, interactional context, quantitative discourse analysis, social meaning, style, tag questions)
from Language in Society
The Effect of Lateral Shift of Cricoid Cartilage on Pharyngeal Swallowing
Abstract Head rotation is widely used as one of the postural techniques for dysphagic patients. However, it cannot be used for patients with severe limitations to the range of motion of the neck. The purpose of this study was to determine the effect of applying pressure to the cricoid while swallowing and to explore the possibility of this maneuver as an alternative to head rotation. The swallowing function of 12 volunteers was examined with videofluorography under nine conditions: neutral, head rotated to the right, head rotated to the left, applying pressure to the cricoid on the right side at 5, 10, and 15 N, and applying pressure to the cricoid on the left side at 5, 10, and 15 N. To examine the effect of this maneuver on pharyngeal swallowing, the laterality of bolus flow was evaluated using 3 ml barium thin liquid from the posterior-anterior (P-A) view. The “pressing-cricoid” maneuver significantly altered the laterality of the bolus flow; the bolus flow was shifted to the side opposite to which the pressure was applied. The results of these changes were similar to those achieved with head rotation. These results demonstrated that the “pressing-cricoid” maneuver changes the bolus flow. This maneuver may have therapeutic value for the treatment of dysphagic patients as an alternative to head rotation.
from Dysphagia
Web-Based Hearing Screening Test
This article describes a Web-based hearing screening system developed for real-time application via Internet and compares efficacy with conventional screening. The present prospective study used 36 adult participants in a double-blind study of two different systems: a conventional audiometer and a Web-based hearing screening test. The audiometric thresholds assessed by these two systems varied by no more than 1.78 dB for air conduction. The results demonstrated the feasibility of this Web-based hearing screening system. This Web-based system can be used effectively and easily in many locations that have Internet access but no local audiologists. The system makes audiometric measurements easily accessible for the public by providing a cost-effective solution based on the software for testing hearing installed in local personal computers or in network servers.
Speech with Gaps: Effects of Periodic Interruptions on Speech Intelligibility Alexander Schnotz, Frank Digeser, Ulrich Hoppe Department of Audiology, ENT Clinic, University of Erlangen-Nuremberg, Erlangen, Germany
Objective: This study examined the role of central auditory completion in speech understanding. The perception of periodically interrupted speech was investigated. For this purpose, gaps were inserted into speech signals by silencing out defined intervals. The main hypothesis was that word recognition increases with shorter gaps and is less influenced by the total amount of gaps. Patients and Methods: Seventeen normal-hearing young adults took part in this study. Phrases from the German HSM speech recognition test were used as speech material. The examination comprised 220 modulated sentences presented binaurally at 65 dB. Intervals with durations ranging from 50 to 700 ms were taken to silence out 50, 65 and 80% of each sentence, respectively. Results: Mean speech perception values were in the range of 65-92%, 35-92% and 35-95% correct answers for gap ratios of 50, 65 and 80%, respectively. When comparing the same interval duration, word recognition was better for smaller gap ratios. Both, gap ratio and gap duration had a significant influence on identification performance. Conclusions: Speech can be understood even when very large proportions are blanked out. A significant decrease in perception can be observed when gap duration exceeds more than half of the syllable length.
Speech with Gaps: Effects of Periodic Interruptions on Speech Intelligibility Alexander Schnotz, Frank Digeser, Ulrich Hoppe Department of Audiology, ENT Clinic, University of Erlangen-Nuremberg, Erlangen, Germany
Objective: This study examined the role of central auditory completion in speech understanding. The perception of periodically interrupted speech was investigated. For this purpose, gaps were inserted into speech signals by silencing out defined intervals. The main hypothesis was that word recognition increases with shorter gaps and is less influenced by the total amount of gaps. Patients and Methods: Seventeen normal-hearing young adults took part in this study. Phrases from the German HSM speech recognition test were used as speech material. The examination comprised 220 modulated sentences presented binaurally at 65 dB. Intervals with durations ranging from 50 to 700 ms were taken to silence out 50, 65 and 80% of each sentence, respectively. Results: Mean speech perception values were in the range of 65-92%, 35-92% and 35-95% correct answers for gap ratios of 50, 65 and 80%, respectively. When comparing the same interval duration, word recognition was better for smaller gap ratios. Both, gap ratio and gap duration had a significant influence on identification performance. Conclusions: Speech can be understood even when very large proportions are blanked out. A significant decrease in perception can be observed when gap duration exceeds more than half of the syllable length.
Neuroimaging of the Functional and Structural Networks Underlying Visuospatial versus Linguistic Reasoning in High-Functioning Autism
High-functioning individuals with autism have been found to favor visuospatial processing in the face of typically poor language abilities. We aimed to examine the neurobiological basis of this difference using functional magnetic resonance imaging and diffusion tensor imaging. We compared 12 children with high functioning autism (HFA) to 12 age- and IQ-matched typically developing controls (CTRL) on a pictorial reasoning paradigm under three conditions: V, requiring visuospatial processing, S, requiring language (i.e. semantic) processing, and V + S, a hybrid condition in which language use could facilitate visuospatial transformations. Activated areas in the brain were chosen as endpoints for probabilistic diffusion tractography to examine tract integrity (FA) within the structural network underlying the activation patterns. The two groups showed similar networks, with linguistic processing activating inferior frontal, superior and middle temporal, ventral visual, and temporo-parietal areas, whereas visuospatial processing activated occipital and inferior parietal cortices. However, HFA appeared to activate occipito-parietal and ventral temporal areas, whereas CTRL relied more on frontal and temporal language regions. The increased reliance on visuospatial abilities in HFA was supported by intact connections between the inferior parietal and the ventral temporal ROIs. In contrast, the inferior frontal region showed reduced connectivity to ventral temporal and middle temporal areas in this group, reflecting impaired activation of frontal language areas in autism. The HFA group’s engagement of posterior brain regions along with its weak connections to frontal language areas suggest support for a reliance on visual mediation in autism, even in tasks of higher cognition.
from Neuropsychologia
Nonverbal auditory agnosia with lesion to Wernicke’s area
We report the case of patient M, who suffered unilateral left posterior temporal and parietal damage, brain regions typically associated with language processing. Language function largely recovered since the infarct, with no measurable speech comprehension impairments. However, the patient exhibited a severe impairment in nonverbal auditory comprehension. We carried out extensive audiological and behavioral testing in order to characterize M’s unusual neuropsychological profile. We also examined the patient’s and controls’ neural responses to verbal and nonverbal auditory stimuli using functional magnetic resonance imaging (fMRI). We verified that the patient exhibited persistent and severe auditory agnosia for nonverbal sounds in the absence of verbal comprehension deficits or peripheral hearing problems. Acoustical analyses suggested that his residual processing of a minority of environmental sounds might rely on his speech processing abilities. In the patient’s brain, contralateral (right) temporal cortex as well as perilesional (left) anterior temporal cortex were strongly responsive to verbal, but not to nonverbal sounds, a pattern that stands in marked contrast to the controls’ data. This substantial reorganization of auditory processing likely supported the recovery of M’s speech processing.
from Neuropsychologia
The Split Fovea Theory and the Leicester Critique: What do the Data Say?
According to the Split Fovea Theory (SFT) recognition of foveally presented words involves interhemispheric transfer. This is because letters to the left of the fixation location are initially sent to the right hemisphere, whereas letters to the right of the fixation position are projected to the left hemisphere. Both sources of information must be integrated for words to be recognized. Evidence for the SFT comes from the Optimal Viewing Position (OVP) paradigm, in which foveal word recognition is examined as a function of the letter fixated. OVP curves are different for left and right language dominant participants, indicating a time cost when information is presented in the halffield ipsilateral to the dominant hemisphere (Hunter, Brysbaert, & Knecht, 2007). The methodology of the SFT research has recently been questioned, because not enough efforts were made to ensure adequate fixation. The aim of the present study is to test the validity of this argument. Experiment 1 replicated the OVP effect in a naming task by presenting words at different fixation positions, with the experimental settings applied in previous OVP research. Experiment 2 monitored and controlled eye fixations of the participants and presented the stimuli within the boundaries of the fovea. Exactly the same OVP curve was obtained. In Experiment 3, the eyes were also tracked and monocular viewing was used. Results again revealed the same OVP effect, although latencies were remarkably higher than in the previous experiments. From these results we can conclude that although noise is present in classical SFT studies without eye-tracking, this does not change the OVP effect observed with left dominant individuals.
from Neuropsychology
Copyright © 2009 Elsevier Inc. All rights reserved. Lexicality drives audio-motor transformations in Broca’s area
Broca’s area is classically associated with speech production. Recently, Broca’s area has also been implicated in speech perception and non-linguistic information processing. With respect to the latter function, Broca’s area is considered to be a central area in a network constituting the human mirror system, which maps observed or heard actions onto motor programs to execute analogous actions. These mechanisms share some similarities with Liberman’s motor theory, where objects of speech perception correspond to listener’s intended articulatory gestures. The aim of the current series of behavioral, TMS and fMRI studies was to test if Broca’s area is indeed implicated in such audio-motor transformations. More specifically, using a classical phonological rhyme priming paradigm, we investigated whether the role of Broca’s area could be purely phonological or rather, is lexical in nature. In the behavioral baseline study, we found a large priming effect in word prime/target pairs (W–W) and no effect for pseudo-words (PW–PW). Online TMS interference of Broca’s area canceled the priming difference between W–W and PW–PW by enhancing the effects for PW–PW. Finally, the fMRI study showed activation of Broca’s area for W–W pairs, but not for PW–PW pairs. Our data show that Broca’s area plays a significant role in speech perception strongly linked to the lexicality of a stimulus.
from Brain and Language
Copyright © 2009 Published by Elsevier B.V. Rate perception and the auditory 40-Hz steady-state fields evoked by two-tone sequences
The rate perception of tone sequences reflects the physical repetition rate for identical sound elements. More complex sequences are perceived at the physical rate or at lower rates, depending on perceptual organization. Here, we used magnetoencephalography and psychophysical studies to evaluate the possible relationship between rate perception of such rapid, 40-Hz tone trains and the 40-Hz steady-state response (SSR) in human primary auditory cortex. In Experiment 1, the 40-Hz SSR evoked by monotone sequences of 1000 and 600 Hz were compared to the response evoked by alternating-tone sequences of the same frequencies. The results showed that the 40-Hz SSR for the alternating-tones was attenuated compared to the monotones. In Experiment 2, frequency differences across a range of 25 – 300 Hz were studied. Compared to a 1000-Hz monotone sequence, the 40-Hz SSR was reduced. Amplitude reduction was most prominent for frequency differences of 200 Hz and more, which were generally perceived with half-the-physical rate. We discuss possible physiological mechanisms of this finding and its relationship to perception.
from Hearing Research
Copyright © 2009 Elsevier B.V. All rights reserved. The Auditory Midbrain of P0065ople with Tinnitus: Abnormal Sound-Evoked Activity Revisited
Sound-evoked fMRI activation of the inferior colliculi (IC) was compared between tinnitus and non-tinnitus subjects matched in threshold (normal), age, depression, and anxiety. Subjects were stimulated with broadband sound in an “on/off” fMRI paradigm with and without on-going sound from the scanner coolant pump.
(1) With pump sounds off, the tinnitus group showed greater stimulus-evoked activation of the IC than the non-tinnitus group, suggesting abnormal gain within the auditory pathway of tinnitus subjects.
(2) Having pump sounds on reduced activation in the tinnitus, but not the non-tinnitus group. This result suggests response saturation in tinnitus subjects, possibly occurring because abnormal gain increased response amplitude to an upper limit.
(3) In contrast to Melcher et al. (2000), the ratio of activation between right and left IC did not differ significantly between tinnitus and non-tinnitus subjects or in a manner dependent on tinnitus laterality. However, new data from subjects imaged previously by Melcher et al. suggest a possible tinnitus subgroup with abnormally asymmetric function of the IC.
The present and previous data together suggest elevated responses to sound in the IC are common among those with tinnitus and normal thresholds, while abnormally asymmetric activation is not, even among those with lateralized tinnitus.
from Hearing Research
Copyright © 2009 Elsevier Ireland Ltd All rights reserved. The role of audiological diagnostics in children with cleft lip & palate (CLP)
Setting
Research study was carried in Post Graduate Institute of Medical Education & Research (PGIMER) which is one of the tertiary care institutions in India.
Participants
55 children (Mch: 28; Fch: 27) in the age range of 4–13 years constituted the study group. These children were operated upon by the same surgeon (JKM) during the period 1996–1998 and were attending the speech clinics at PGIMER. None of these children/parents had complained of any ear problem and were taken up for the study to find out the middle ear pathology. The ontological and audiological evaluation was done for all the children.
Results
53 of 110 ears had normal hearing status. None of the ears had severe or profound hearing loss. The air conduction thresholds ranged from 20.2 to 29.63 dB across the frequencies whereas the bone conduction thresholds varied from 7.13 to 12.41 dB. Only 42% of the right (R) ears and 47% of the left (L) ears had a normal tympanic membrane.
Conclusion
On the basis of this finding, investigation of the benefits of early and routine follow-up for otologic and audiologic status is warranted. Patients with cleft lip and palate should have an intense and detailed otologic and audiologic follow-up to identify any ME pathology/hearing loss so that timely intervention can be taken.
from the International Journal of Pediatric Otorhinolaryngology
Auditory stream biasing in children with reading impairments
Reading impairments have previously been associated with auditory processing differences. We examined auditory stream biasing, a global aspect of auditory temporal processing. Children with reading impairments, control children and adults heard a 10 s long stream-bias-inducing sound sequence (a repeating 1000 Hz tone) and a test sequence (eight repetitions of two pure tones of 1000 and 1420 Hz in an XYX-XYX pattern) with a variable delay interval (from 0.09 to 8 s) between the two sequences. Reading-impaired children had a significantly lower proportion of streamed responses than control children and adults. Streamed responses in reading-impaired participants differed according to their musical experience, but musically experienced reading-impaired participants were still significantly different from musically experienced controls. Reading impairments are associated with global differences in auditory integration, and musical experience needs to be considered when investigating auditory processing capabilities. Copyright © 2009 John Wiley & Sons, Ltd.
Cognitive outcome following unilateral arterial ischaemic stroke in childhood: effects of age at stroke and lesion location
Results Measures of overall intelligence, verbal ability, working memory, and processing speed were significantly lower in children who had had a stroke than in the normative sample (all z>2.5, all p<0.01). The perinatal group performed more poorly than the other two groups on most cognitive measures, regardless of lesion location. The combined lesion location group performed more poorly than those with damage to either cortical or subcortical areas alone. Further investigation revealed different periods of peak vulnerability for subcortical lesions (perinatal) and cortical lesions (1mo–5y).
Method Using age-appropriate Wechsler scales of intellectual ability, we explored this issue by evaluating a large group (n=145) of children (89 males, 56 females) who experienced unilateral arterial ischaemic stroke during the perinatal period (diagnosed mean 73d, SD 29d), between the ages of 1 month and 5 years (mean 2y 10mo, SD 1y 9mo), or between the ages of 6 and 16 years (mean 11y 1mo SD 3y 6mo). The mean age at assessment was 8 years (SD 3y 10mo) in the perinatal group, 7 years 5 months (SD 2y 9mo) in the 1 month to 5 years group, and 12 years 5 months (SD 3y 9mo) in the 6 to 16 years group. The mean time interval between stroke and assessment was 8 years (SD 18d) for perinatal, 4 years 6 months (SD 1y 5mo) for 1 month to 5 years, and 1 year 4 months (SD 2y 9mo) for 6 to 16 years. The relationship between age at stroke and lesion location (subcortical, cortical, or combined) as it pertains to cognitive outcome was also examined.
