Kerttu Huttunen

Effect of cognitive load on speech prosody in aviation: Evidence from military simulator flights.

Mental overload directly affects safety in aviation and needs to be alleviated. Speech recordings are obtained non-invasively and as such are feasible for monitoring cognitive load. We recorded speech of 13 military pilots while they were performing a simulator task. Three types of cognitive load (load on situation awareness, information processing and decision making) were rated by a flight instructor separately for each flight phase and participant. As a function of increased cognitive load, the mean utterance-level fundamental frequency (F0) increased, on average, by 7 Hz and the mean vocal intensity increased by 1 dB. In the most intensive simulator flight phases, mean F0 increased by 12 Hz and mean intensity, by 1.5 dB. At the same time, the mean F0 range decreased by 5 Hz, on average. Our results showed that prosodic features of speech can be used to monitor speaker state and support pilot training in a simulator environment.

Cochlear implant patients and quality of life

During the last two decades, cochlear implants have been available for profoundly hearing-impaired patients who do not benefit from conventional hearing aids. The quality of life of these implantees has not been extensively studied, and has not been studied at all in Finland. To assess their quality of life, the Nottingham Health Profile questionnaire was sent to all adult implanted patients in Finland. Implantees tended to have more favourable average pain, emotional reaction and mobility indexes in each age group studied than the average population. Social isolation seemed to be more common in the youngest and oldest age groups of implantees. Apparently, implantees are physically healthier than the average population. However, a bias caused by the strict selection of implant candidates cannot be excluded.

Parents' Views on Changes in Their Child's Communication and Linguistic and Socioemotional Development After Cochlear Implantation

Our aim was to obtain versatile information on the communication and socioemotional development of implanted children in their everyday environment. We studied 18 children implanted unilaterally at the mean age of 3 years 4 months. All had normal nonverbal intelligence, but 8 (44%) had concomitant problems. Their parents filled out semistructured questionnaires at 6 months and then annually 1-5 years after activation. Parents reported a change from use of signs to speech, and changes in the childrens vocal behavior and spoken language development. They also reported that children had calmed down and showed an increased sense of self-confidence and safety with an expanded social life. The greatest changes started to take place 1 year after implantation. Five years after implantation, two thirds of children were judged to be as independent as their age peers. We conclude that changes in communication pave the way to benefits in psychosocial development after implantation.

Cochlear implants and GSM phones

Use of a telephone and GSM phones, in particular, was assessed by means of a postal interview sent to all adult Finnish implantees. The response rate was very high (87%). Fifty-one of the 61 respondents used a telephone and 27/61 also used a mobile phone, usually a digital phone. Two GSM phone models from Nokia (3110 and 6110) were tested with three different cochlear implant systems used by nine patients. Definite differences between the processors were found. Nucleus Spectra (two implantees) could not be used with any of the GSM phones under any test condition. Nucleus SPrint was incompatible with both GSM phone models in a poor field, while GSM phone model 6110 could be used in a good field. The Med-El Combi 40+ processor was compatible with both GSM models tested under any condition.

Development of speech intelligibility and narrative abilities and their interrelationship three and five years after paediatric cochlear implantation.

This study sought to determine the level of speech intelligibility, narrative abilities, and their interrelationship in 18 Finnish children implanted at the average age of three years, four months. Additionally, background factors associated with speech intelligibility and storytelling ability were examined. Speech intelligibility was examined by means of an item identification task with five listeners per child. Three and five years after activation of the implant, the children reached average intelligibility scores of 53% and 81%, respectively. The story generation abilities of the implanted children exceeded their hearing age by one year, on average. This was found after comparing their results with those of normally-hearing two- to six-year-olds (N = 49). According to multiple regression analysis, comorbidity (number of additional needs), chronological age, and/or age at activation usually explained from 46% to 70% of the variation in speech intelligibility and narrative abilities. After controlling for age, communication mode, and number of additional needs, speech intelligibility and ability to narrate were statistically significantly associated with each other three years after activation, but not anymore five years after activation.

Effect of Caffeine on Vigilance and Cognitive Performance During Extended Wakefulness

In this double-blind, randomized, 37-hr sleep deprivation study, 15 military pilot students received either placebo or 200 mg of caffeine twice a day. Vigilance was assessed 6 times and learning 4 times, both in a computerized environment. Motivation, mood, and sleepiness were monitored using self-ratings. In the vigilance test, sleep deprivation decreased the amount of correct detections and increased reaction times in both groups. Furthermore, the number of false alarms increased in the placebo group. Participants receiving caffeine showed overconfidence, as they did not report any clear decline in subjectively assessed success despite impaired performance in the vigilance test.

Phonological development in 4-6-year-old moderately hearing impaired children

The acquisition of clear phonological rules is of utmost importance for a child when he/she is learning to decode and convey meanings using spoken language. Fifteen Finnish-speaking children, five normally hearing (NH) 3-year-olds and 10 moderately hearing impaired (HId) 4-6-year-olds were studied here. Speech samples consisting of 62 words were collected from each child during a picture naming task. Frequent phonetic (articulation) errors together with normal (but delayed) and deviant phonological processes of HId children were found in this study. The frequency and quality of the processes seemed to be related more to the grade of HI than, for example, the age of the child. Implications for speech therapy are briefly discussed.

Methodological aspects of assessing speech intelligibility among children with impaired hearing

Objective In the assessment of speech intelligibility, procedures that are easy to use, but also valid and reliable, are needed. The aim of this study was to explore the reliability and concurrent validity of two scaling methods for assessing the speech intelligibility of children with impaired hearing. Material and Methods A total of 51 children aged 4–17 years with a mild to profound hearing impairment performed a naming task comprising 62 single words. Altogether, 85 inexperienced listeners, divided into 17 panels, assessed the speech production of the children. A percent correct score (for identification of the words) was obtained from every listener. The listeners were also asked to judge the overall intelligibility of each child using a visual analogue scale (VAS) and a four-point ordinal level rating scale with verbal descriptors. Results The percent correct score correlated significantly both with the VAS and the rating scale with verbal descriptors (Pearsons’ coefficient 0.90 and Spearmans coefficient 0.78, respectively). Also, the VAS and the scale with verbal descriptors were significantly intercorrelated (Spearmans rho 0.85). Moderate to high correlations were usually obtained for all grades of hearing impairment, both sexes, different age groups and main communication modes. Conclusions Especially for assessing the need for remediation of speech and in monitoring its effectiveness, a quick overall estimate of speech intelligibility can be obtained quite reliably using the above rating scales. Item identification is more time-consuming but is often needed in research and therapy planning, where acoustic and linguistic phenomena that reduce intelligibility need to be traced.

Hearing aid users benefit from induction loop when using digital cellular phones.

Objective Hearing aid users have recently been reported to experience problems with electromagnetic interference when using digital cellular phones. This study was undertaken to investigate the possible benefit of an induction loop system developed for use with some cellular phone models, and also to compare the possible benefit in two languages (Finnish and American English) as well as the benefit with two hearing aid technologies (analog versus digital). Design The study was performed in controlled laboratory conditions at two tertiary care hearing health care centers, one in Oulu, Finland and the other in Dallas, in the United States. The subjects were experienced users of behind-the-ear hearing aids and served as their own controls in three different listening conditions. Thirty-two eligible subjects (20 in Oulu and 12 in Dallas) participated in three test conditions: 1. call with a landline phone, 2. call with a digital cellular phone alone and 3. call with a digital cellular phone coupled to an induction loop. Results Sentence recognition scores and subjective judgments using a visual analog scale revealed the poorest results with the digital cellular phone alone. When the induction loop was used with the digital cellular phones, sentence recognition scores and the visual analog scale scores were comparable to the scores obtained with a landline phone. The mean sentence recognition score for analog hearing aids was 62.4% (95% confidence interval 50.2 to 74.6) with the landline phone, 12.6% (−1.6 to 26.9) with the digital cellular phone alone, and 63.3% (44.2 to 82.3) when using the digital cellular phone with the induction loop. For digital hearing aids, the sentence recognition scores were 62.4% (51.9 to 72.9), 37.4% (18.0 to 56.8) and 57.6% (39.0 to 76.2), respectively. There was no significant difference in performance between the two centers. However, when using the digital cellular phone alone, there was no drop in the sentence recognition scores with the few (N = 5) digital hearing aids in Dallas. The subjects ranked the digital cellular phone alone as the poorest test condition and the digital cellular phone with an induction loop as the best. Conclusions Induction loops appear to offer one possible solution for the incompatibility problem between hearing aids and digital cellular phones. However, the generalizability of the results must be viewed cautiously, because testing included only one induction loop and two digital cellular phone models.

How children with normal hearing and children with a cochlear implant use mentalizing vocabulary and other evaluative expressions in their narratives

This study explored the use of mental state and emotion terms and other evaluative expressions in the story generation of 65 children (aged 2–8 years) with normal hearing (NH) and 11 children (aged 3–7 years) using a cochlear implant (CI). Children generated stories on the basis of sets of sequential pictures. The stories of the children with CI were obtained over the 5-year follow-up period. The children with NH continued to show an increased story length (number of words) with age. In the children with a CI, the increase was similar initially, but plateaued after 3 years of using a CI. In children with NH, the spontaneous use of mental state vocabulary in narratives increased significantly between the ages of three and six. The delayed use of mental state terms in the children with a CI was related to a reduced amount of linguistic production overall. The theoretical and clinical implications were discussed.