Monthly Archives: October 2009
THE RELATIONSHIP BETWEEN L1 FLUENCY AND L2 FLUENCY DEVELOPMENT
A fundamental question in the study of second language (L2) fluency is the extent to which temporal characteristics of speakers’ first language (L1) productions predict the same characteristics in the L2. A close relationship between a speaker’s L1 and L2 temporal characteristics would suggest that fluency is governed by an underlying trait. This longitudinal investigation compared L1 and L2 English fluency at three times over 2 years in Russian- and Ukrainian- (which we will refer to here as Slavic) and Mandarin-speaking adult immigrants to Canada. Fluency ratings of narratives by trained judges indicated a relationship between the L1 and the L2 in the initial stages of L2 exposure, although this relationship was found to be stronger in the Slavic than in the Mandarin learners. Pauses per second, speech rate, and pruned syllables per second were all related to the listeners’ judgments in both languages, although vowel durations were not. Between-group differences may reflect differential exposure to spoken English and a closer relationship between Slavic languages and English than between Mandarin and English. Suggestions for pedagogical interventions and further research are also proposed.
1
Correlations between measures of executive attention and cortical thickness of left posterior middle frontal gyrus – a dichotic listening study
Background
The frontal lobe has been associated to a wide range of cognitive control functions and is also vulnerable to degeneration in old age. A recent study by Thomsen and colleagues showed a difference between a young and old sample in grey matter density and activation in the left middle frontal cortex (MFC) and performance on a dichotic listening task. The present study investigated this brain behaviour association within a sample of healthy older individuals, and predicted a positive correlation between performance in a condition requiring executive attention and measures of grey matter structure of the posterior left MFC.
Methods
A dichotic listening forced attention paradigm was used to measure attention control functions. Subjects were instructed to report only the left or the right ear syllable of a dichotically presented consonant-vowel syllable pair. A conflict situation appears when subjects are instructed to report the left ear stimulus, caused by the conflict with the bottom-up, stimulus-driven right ear advantage. Overcoming this processing conflict was used as a measure of executive attention. Thickness and volumes of frontal lobe regions were derived from automated segmentation of 3D magnetic resonance image acquisitions.
Results
The results revealed a statistically significant positive correlation between the thickness measure of the left posterior MFC and performance on the dichotic listening measures of executive attention. Follow-up analyses showed that this correlation was only statistically significant in the subgroup that showed the typical bottom-up, stimulus-driven right ear advantage.
Conclusion
The results suggest that the left MFC is a part of an executive attention network, and that the dichotic listening forced attention paradigm may be a feasible tool for assessing subtle attentional dysfunctions in older adults.
The shape of words in the brain
The principle of arbitrariness in language assumes that there is no intrinsic relationship between linguistic signs and their referents. However, a growing body of sound-symbolism research suggests the existence of some naturally-biased mappings between phonological properties of labels and perceptual properties of their referents (Maurer, Pathman, & Mondloch, 2006). We present new behavioural and neurophysiological evidence for the psychological reality of sound-symbolism. In a categorisation task that captures the processes involved in natural language interpretation, participants were faster to identify novel objects when label–object mappings were sound-symbolic than when they were not. Moreover, early negative EEG-waveforms indicated a sensitivity to sound-symbolic label–object associations (within 200 ms of object presentation), highlighting the non-arbitrary relation between the objects and the labels used to name them. This sensitivity to sound-symbolic label–object associations may reflect a more general process of auditory–visual feature integration where properties of auditory stimuli facilitate a mapping to specific visual features.
Canada’s first nationwide hearing healthcare structure launched
Lifestyle Hearing Corporation has officially launched Canada’s first nationwide hearing healthcare structure called the Lifestyle Hearing Network. This initiative aims to provide Canadians coast to coast with a consistent source of premium medical clinics devoted to audiology.
from News-Medical.net
Scientists Discover Gene Key to Human Speech
A gene that plays a role in human vocal development and speech has been identified by an international team of scientists.
from MedlinePlus
Blogger Discusses the Psychological Side of Stuttering
In a recent blog post, a blogger called “Stuttering Jack” offers his opinion on how stuttering increases people’s anxieties and destructs their confidence. He suggests several methods for treating the negative psychological effects of stuttering,such as cognitive behavior therapy and neuro linguistic programming.
from Presence TeleCare
Less Sensitivity to Hormone May Play Role in Autism
A new genetic signature that’s strongly associated with autism has been identified by U.S. researchers, who said the finding may lead to new ways to diagnose and treat the disorder.
from MedicineNet.com
Now hear this
Reporting on rat experiments in the October 22 issue of Nature, a Johns Hopkins team says it has for what is believed to be the first time managed to measure and record the elusive electrical activity of the type II neurons in the snail-shell-like structure called the cochlea. And it turns out the cells do indeed carry signals from the ear to the brain, and the sounds they likely respond to would need to be loud, such as sirens or alarms that might be even be described as painful or traumatic.
from EurekAlert.org
VOCABULARY KNOWLEDGE AND ADVANCED LISTENING COMPREHENSION IN ENGLISH AS A FOREIGN LANGUAGE
This article presents an empirical study that investigates the role of vocabulary knowledge in listening comprehension with 115 advanced Danish learners of English as a foreign language (EFL). The dimensions of depth and breadth of vocabulary knowledge (measured by the Vocabulary Levels Test and the Word Associates Test) were found to be significantly correlated with listening comprehension (measured by a listening test from the Cambridge certificate of proficiency in English) and could predict half of the variance in the listening scores. This study thus provides empirical evidence that vocabulary knowledge is an important factor for successful listening comprehension in EFL. Furthermore, the results suggest that a lexical coverage of 98% is needed for coping with the spoken texts that constitute the listening test. This coverage figure is consistent with findings from reading research.
Learning Strategy Trumps Motivational Level In Determining Learning-Induced Auditory Cortical Plasticity
Associative memory for auditory-cued events involves specific plasticity in the primary auditory cortex (A1) that facilitates responses to tones which gain behavioral significance, by modifying representational parameters of sensory coding. Learning strategy, rather than the amount or content of learning, can determine this learning-induced cortical (high order) associative representational plasticity (HARP). Thus, tone-contingent learning with signaled errors can be accomplished either by (1) responding only during tone duration (“tone-duration” strategy, T-Dur), or (2) responding from tone onset until receiving an error signal for responses made immediately after tone offset (“tone-onset-to-error”, TOTE). While rats using both strategies achieve the same high level of performance, only those using the TOTE strategy develop HARP, viz., frequency-specific decreased threshold (increased sensitivity) and decreased bandwidth (increased selectivity) (Berlau and Weinberger, 2008). The present study challenged the generality of learning strategy by determining if high motivation dominates in the formation of HARP. Two groups of adult male rats were trained to bar-press during a 5.0 kHz (10s, 70 dB) tone for a water reward under either high (HiMot) or moderate (ModMot) levels of motivation. The HiMot group achieved a higher level of correct performance. However, terminal mapping of A1 showed that only the ModMot group developed HARP, i.e., increased sensitivity and selectivity in the signal frequency band. Behavioral analysis revealed that the ModMot group used the TOTE strategy while HiMot subjects used the T-Dur strategy. Thus, type of learning strategy, not level of learning or motivation, is dominant for the formation of cortical plasticity.
Phonological knowledge guides 2-year-olds’ and adults’ interpretation of salient pitch contours in word learning
Phonology provides a system by which a limited number of types of phonetic variation can signal communicative intentions at multiple levels of linguistic analysis. Because phonologies vary from language to language, acquiring the phonology of a language demands learning to attribute phonetic variation appropriately. Here, we studied the case of pitch-contour variation. In English, pitch contour does not differentiate words, but serves other functions, like marking yes/no questions and conveying emotions. We show that, in accordance with their phonology, English-speaking adults and 2-year-olds do not interpret salient pitch contours as inherent to novel words. We taught participants a new word with consistent segmental and pitch characteristics, and then tested word recognition for trained and deviant pronunciations using an eyegaze-based procedure. Vowel-quality mispronunciations impaired recognition, but large changes in pitch contour did not. By age 2, children already apply their knowledge of English phonology to interpret phonetic consistencies in their experience with words.
from the Journal of Memory and Language
Recording of electrically evoked auditory brainstem responses after electrical stimulation with biphasic, triphasic and precision triphasic pulses
Biphasic electrical pulses are the standard stimulation pulses in current cochlear implants. In auditory brainstem recordings biphasic pulses generate a significant artifact that disrupts brainstem responses, which are magnitudes smaller. Triphasic pulses may minimize artifacts by restoring the neural membrane to its resting potential faster than biphasic pulses and make auditory brainstem responses detection easier. We compared biphasic pulses with triphasic and precision triphasic pulses to evoke brainstem responses in human subjects. For this purpose, electrically evoked brainstem response audiometry was performed in 10 (11 ears) cochlear implant patients. Artifacts and brainstem responses evoked by bi- and triphasic stimulation were analyzed. Artifact amplitude and decay time were related to pulse pattern shape, but application of averaging and alternation reduced the deterioration of electrically evoked brainstem responses independent of pulse pattern shape. Contrary to our expectations, biphasic pulses showed a higher detectability in comparison to triphasic pulse stimulation at the same stimulation amplitude.
from the Journal of Voice
Change in Vibrato Rate and Extent During Tertiary Training in Classical Singing Students
Objectives
Vibrato is an integral and desirable feature of the classical singing voice. For elite singing students, achieving and developing vibrato may constitute one of the essential elements of their vocal training, although it is not necessarily a focus of that training.
Study Design
In this longitudinal study, we measured vibrato rate (VR) and vibrato extent (VE) and regularity (SD) of VR and VE in student singers over the course of four semesters of tertiary level voice training at a conservatorium of music to determine how these parameters changed during training.
Method
Fifteen singers completed four semesters (2 years) of training. Singers performed four sustained pitches across their vocal range. Peaks and troughs of vibrato were isolated from the fundamental frequency trace to calculate VR in hertz and VE in semitones.
Results
Analysis using linear mixed models revealed significant increases in VE and decreases in VRSD over time. VR was within expected limits for classical singers in all semesters, and small VR reductions were not statistically significant between semesters over 2 years of training. VE showed significant increases between the start of year 1 and year 2. Periodicity of singers’ VR (SD) improved over training, with significant decreases to VRSD over time. There was no significant change to VESD.
Conclusions
Future studies will ascertain whether further changes to VR and VE occur over longer training periods, or whether the major changes occur early in tertiary training.
from the Journal of Voice
The Butterfly Procedure: A New Technique and Review of the Literature for Treating Anterior Laryngeal Webs
Congenital laryngeal webs, subglottic stenosis, and laryngeal atresia result from various degrees of failure of airway recanalization as a spectrum. The symptoms also range from asymptomatic to dysphonia and severe airway obstruction. There are a number of methods for management of symptomatic patients. In this article, we discuss a new procedure that was used in the management of two anterior laryngeal web patients with relatively acceptable results.
from the Journal of Voice
Whispering—A Single-Subject Study of Glottal Configuration and Aerodynamics
Whisper productions were produced by a single adult male subject over a wide range of subglottal pressures, glottal areas, and glottal flows. Dimensional measurements were made of these three variables, including glottal perimeter. Subglottal pressure was directly obtained by a pressure transducer in a tracheal catheter, and wide-band flow with a pneumotach mask. Four types of whispers were used—hyperfunctional, hypofunctional, neutral, and postphonation—in addition to three levels of loudness (soft, medium, loud). Sequences of the /pae/ syllable were used. Video recordings of the larynx were made. The glottis was outlined by hand with extrapolation for unseen parts, and area and perimeter were obtained through image analysis software. The whisper tokens resulted in the following wide ranges: subglottal pressure: 1.3–17 cm H2O; glottal flow: 0.9–1.71 L/s; glottal area: 0.065–1.76 cm2; and glottal perimeter: 1.09–6.55 cm. Hyperfunctional whisper tended to have higher subglottal pressures and lower areas and flows than hypofunctional whisper, with neutral and postphonation whisper values in between. An important finding is that glottal flow changed more for small changes of area when the area was already small, and did not create much flow change when area was changed for already larger areas; that is, whisper is “more sensitive” to airflow changes for smaller glottal areas. A general equation for whisper aerodynamics was obtained, namely, P (subglottal pressure [cm H2O]) = C × F (glottal flow [cm3/s]), where C = 0.052 × A4 − 0.1913 × A3 + 0.2577 × A2 − 0.1523 × A + 0.0388, where A is the glottal area (cm2). Another general equation for nondimensional terms (pressure coefficient vs Reynolds number) also is offered. Implications for whisper flow resistance and aerodynamic power are given. These results give insight into whisper aerodynamics and offer equations relevant to speech synthesis.
from the Journal of Voice
