Situating language production within the matrix of human cognition: The state of the art in language production research

from Language and Cognitive Processes

A summary of recent work in language production is presented, focusing on the Third International Workshop on Language Production (Chicago, USA, August 2006). The articles included in this special issue focus on three overlapping themes: language production in dialogue (Arnold; Costa, Pickering, & Sorace); multilingual language production (Costa et al.; Abutalebi & Green); and control processes in production (Abutalebi & Green; Dell, Oppenheim, & Kittredge). Points of convergence and divergence between these contributions are discussed.

Central timing deficits in subtypes of primary speech disorders

from Clinical Linguistics and Phonetics

Childhood apraxia of speech (CAS) is a proposed speech disorder subtype that interferes with motor planning and/or programming, affecting prosody in many cases. Pilot data (Peter & Stoel-Gammon, 2005) were consistent with the notion that deficits in timing accuracy in speech and music-related tasks may be associated with CAS. This study replicated and expanded earlier findings. Eleven children with speech disorders and age-and gender-matched controls participated in non-word imitation, clapped rhythm imitation, and paced repetitive tapping tasks. Results suggest a central timing deficit, expressed in both the oral and the limb modality, and observable in two different types of timing measures, overall rhythmic structures and small-scale durations. Associations among timing measures were strongest in the participants with speech disorders, who also showed lower timing accuracy than the controls in all measures. The number of observed CAS characteristics was associated with timing deficits.

An investigation of voice quality in individuals with inherited elastin gene abnormalities

from Clinical Linguistics and Phonetics

The human elastin gene (ELN) is responsible for the generation of elastic fibres in the extracellular matrix of connective tissue throughout the body, including the vocal folds. Individuals with Supravalvular aortic stenosis (SVAS) and Williams syndrome (WS) lack one normal ELN allele due to heterozygous ELN abnormalities, resulting in a haploinsufficiency. We measured perceptual and acoustic characteristics of voice quality in individuals with SVAS and WS to investigate the consequences to vocal function secondary to ELN haploinsufficiency. Results indicated that the voice quality of individuals with SVAS/WS was rated as significantly more abnormal, rough, and hoarse compared to normal controls, and that adults with SVAS/WS were rated as significantly lower in pitch. Acoustic measures indicated that individuals with SVAS/WS produced greater instability of fundamental frequency during phonation (as reflected via increased pitch sigma and increased jitter). These findings support the possibility that heterozygous ELN abnormalities negatively influence vocal fold biomechanics and the resulting sound produced by the vibrating glottis.

Fortition and lenition patterns in the acquisition of obstruents by children with cochlear implants

from Clinical Linguistics and Phonetics

This paper investigates patterns of error production in 10 children who use cochlear implants, focusing specifically on the acquisition of obstruents. Two broad patterns of production errors are investigated, fortition (or strengthening) errors and lenition (or weakening) errors. It is proposed that fortition error patterns tend to be related to the process of phonological development, because they are involved with universal implications and notions of markedness. Lenition error patterns, on the other hand, show more context-sensitive effects and reflect properties related to minimization of articulatory effort. The relationship between fortition and markedness is demonstrated in an optimality theoretic analysis, and it is further demonstrated that the observed characteristics of phonological development in children with cochlear implants are similar to those exhibited by children with normal hearing.

Prosodic boundaries in alaryngeal speech

from Clinical Linguistics and Phonetics

Alaryngeal speakers (speakers in whom the larynx has been removed) have inconsistent control over acoustic parameters such as F0 and duration. This study investigated whether proficient tracheoesophageal and oesophageal speakers consistently convey phrase boundaries. It was further investigated if these alaryngeal speakers used the same hierarchy of acoustic boundary cues that is found in normal speakers. A perception experiment revealed that listeners identified prosodic boundaries less accurately in oesophageal speakers. Acoustic analyses showed that laryngeal speakers used pre-boundary lengthening and pitch movements at phrase boundaries, as expected. Tracheoesophageal speakers used pre-boundary-lengthening and pauses and oesophageal speakers used pauses to convey phrase boundaries. Two oesophageal speakers also paused inappropriately, within phrases. Although these two speakers differentiated between air-injection and prosodic pauses, listeners were unable to tell the two types of pauses apart. Alaryngeal speakers might benefit from therapy that specifically teaches them how to optimize their prosodic abilities.

A comparison between the feeling of ear fullness and tinnitus in acute sensorineural hearing loss

from the International Journal of Audiology

The feeling of ear fullness (FEF) occurs frequently in patients with acute sensorineural hearing loss; the same is true for tinnitus (TIN). However, the cause of FEF in these patients is unclear. This study included 171 ears of patients admitted with unilateral sudden deafness to the ENT division of Fukuoka University Hospital between January 2001 and December 2004. The results showed TIN was mainly associated with worse high-frequency hearing thresholds, where hearing loss was relatively severe, and this association became stronger after the hearing threshold stabilized. FEF was associated with the low-frequency region, where hearing loss was relatively mild, and this association disappeared after the hearing threshold stabilized. In conclusion, TIN is thought to originate in the region where hair cells are impaired; in contrast, FEF may originate from some functional factor rather than an organic lesion of the cochlea.

Effectiveness of hearing protector devices in impulse noise verified with transiently evoked and distortion product otoacoustic emissions

from the International Journal of Audiology

This study aimed to evaluate the effect of impulse noise on otoacoustic emissions (OAEs) while a passive non-linear earplug or an active level-dependent earmuff was worn.

Since none of the standardized attenuation measurement techniques, REAT (real ear at threshold), ATF (acoustic test fixture), or MIRE (microphone in real ear), is designed to test both types in real-wearing condition, OAEs, suitable for detecting subtle changes in the functional integrity of the cochlear outer hair cells, are used.

First, DPOAEs (distortion product) and TEOAEs (transiently evoked) of 24 subjects were compared before, immediately after gunfire practice, and after one hour of non-exposure. Secondly, both types of OAEs were evaluated in 31 subjects before and after exposure during a five-day military practice.

Significant differences existed between the ears in most cases; the emissions from the right ear had a tendency to be more robust. There were no significant changes in OAEs either before and after exposure, or in the second experiment over multiple days. These findings suggest that the HPDs are able to prevent cochlear damage.

Iris pigmentation and susceptibility to noise-induced hearing loss

from the International Journal of Audiology

The purpose of this retrospective study is to examine the possible association between iris pigmentation and susceptibility to noise-induced hearing loss in 2407 noise-exposed workers. The workers were between 16 to 65 years of age and were exposed to 2 to 42 years of work-related noise. Results demonstrated that dark-eyed workers presented a greater percentage of normal pure-tone thresholds than fair-eyed workers. Fair-eyed workers had threshold averages of 25.1 dB (right ear) and 26.0 dB (left ear) at 3, 4, and 6 kHz, which were significantly worse than workers with dark irises, with threshold averages of 15.8 dB and 17.2 dB in the right and left ear, respectively (p<0.01). Fair-eyed workers with less than 10 years of noise exposure had the same audiometric pattern as the dark-eyed workers exposed for more than 10 years. Workers not exposed to noise did not present significant differences in their audiometric pattern as a function of eye colour. These results suggest that iris pigmentation may be an additional indication of susceptibility to noise-induced hearing loss.

Is the relation of social class to change in hearing threshold levels from childhood to middle age explained by noise, smoking, and drinking behaviour?

from the International Journal of Audiology

Recent work shows that variation in adult hearing function is related both to social class of origin and current social class. This study examines how much of this relationship after adjustment for childhood hearing impairment is explicable by occupational noise, current smoking, and alcohol consumption. A cohort of 9023 persons born in the UK during one week in 1958 was followed periodically, and hearing threshold levels (HTLs) were measured at 1 kHz and 4 kHz at age 45 years. Most (71% and 68%, at 1 kHz and 4 kHz respectively) of the relation to social class of origin of adult HTLs remains after adjustment for these other factors. For the relation to current social class, corresponding values are 64% and 44% (though varying by gender). The magnitude of social class effect is comparable to that of occupational noise. Susceptibility to hearing impairment is likely to be appreciably determined in early childhood.

The effect of hearing impairment in older people on the spouse

from the International Journal of Audiology

The prevalence of hearing impairment (HI) in older people and its detrimental effects on their quality of life and well-being is well known. To date however, there have been few studies investigating the impact on the person’s spouse. To investigate this topic, a qualitative study consisting of in-depth interviews was conducted with five female and five male spouses of older people with HI. The aims of the study were: (1) to describe the spouses’ experiences of living with someone with a HI; (2) to describe the effect of HI on the couples’ communication and relationship; and (3) to identify coping strategies adopted by spouses. An interpretive analysis revealed four themes that described the experience of spouses of older people with HI: (1) the broad ranging effects of the HI on the spouses’ everyday lives; (2) the spouses’ need to constantly adapt to their partners’ HI; (3) the effect of acceptance of the HI on the spouse; and (4) the impact of ageing and retirement. Spouses in this study experienced a wide range of effects as a result of their partners’ HI. Implications for audiological rehabilitation are discussed.

The risk of tinnitus following occupational noise exposure in workers with hearing loss or normal hearing

from the International Journal of Audiology

The purpose was to investigate the relationship between noise exposure and tinnitus among workers with normal hearing and hearing loss, respectively. We conducted a cross-sectional survey of 752 workers employed at 91 workplaces, that were investigated by means of full work-shift noise levels, questionnaire data, and bilateral pure-tone audiometry. Tinnitus was not associated with the present noise level, the duration of noise exposure, or the cumulative noise exposure if participants had normal hearing. As expected, such trends were demonstrated if participants had a hearing handicap. Based on these data, we will be cautious in ascribing tinnitus to noise exposure in our patients’ workplaces if they have a normal audiogram. Furthermore our data indicates no risk of noise-induced tinnitus at exposure levels where no hearing loss would be expected, e.g. as usually encountered in non-industrial workplaces.

Cataract Prevalence, Alternative Glaucoma Therapies Online, Seatbelts Vs. Airbags, And Hearing Loss In Glaucoma Patients

from Medical News Today.com

An Eye Disease or Systemic Disorder? Hearing Loss Study Adds to the Evidence Shahin Yazdani, MD, and his research team evaluated whether patients with ocular pseudoexfoliation syndrome—the most common cause worldwide of the form of glaucoma known as “secondary open angle”—had a higher incidence of hearing loss. In ocular pseudoexfoliation (also called “exfoliation”) syndrome, fibrous white deposits aggregate on the iris, lens and other parts of the eye and can block fluid drainage; this blockage increases intraocular pressure, which can damage the optic nerve. Similar fibrillar deposits have been found in the heart, blood vessels, lung, liver, kidneys and skin of patients with ocular pseudoexfoliation. In addition, pseudoexfoliation has been associated with ischemic heart disease. systemic hypertension, aneurysms, Alzheimer’s disease, and age-related macular degeneration (AMD). The researchers hypothesized that the hearing organs might also be affected after noticing hearing disability in many pseudoexfoliation patients.

Chimp and human communication trace to same brain region

from EurekAlert.org

An area of the brain involved in the planning and production of spoken and signed language in humans plays a similar role in chimpanzee communication, researchers report online on February 28th in the journal Current Biology, a publication of Cell Press.