Hearing and cognition in speech comprehension. Methods and applications

Central auditory processing is complex and can not be evaluated by a single method. This thesis focuses on assessment of some aspects of central auditory functions by the use of dichotic speech tests and cognitive tests that tax functions important for speech processing. Paper A deals with the cognitive effects in dichotic speech testing in elderly hearing-impaired subjects. It was found that different listening tasks in the dichotic tests put different demands on cognitive ability, shown by a varying degree of correlation between cognitive functions and dichotic test parameters. Age-related cognitive decline was strongly connected with problems to perceive stimuli presented to the left ear. Paper B presents a new cognitive test battery sensitive for functions important for speech processing and understanding, performed in text, auditory and audiovisual modalities. The test battery was evaluated in four groups, differing in age and hearing status, and has proven to be useful in assessing the relative contribution of different input-modalities and the effect of age, hearingimpairment and visual contribution on functions important for speech processing. In Paper C the test battery developed in Paper B was used to study listening situations with different kinds of background noise. Interfering noise at +10 dB signal-to-noise ratio has significant negative effects on performance in speech processing tasks and on the effort perceived. Hearing-impaired subjects showed poorer results in noise with temporal variations, and elderly subjects were more distracted by noise with temporal variations, especially by noise with meaningful content. In noise, all subjects, particularly those with impaired hearing, were more dependent upon visual cues than in the quiet condition. Hearing aid benefit in speech processing with and without background noise was studied in Paper D. The test battery developed in Paper B was used together with a standard measure of speech recognition. With hearing aids, speech recognition was improved in the background condition without noise and in the background condition of ordinary speech. Significantly less effort was perceived in the cognitive tests when hearing aids were used, although only minor benefits of hearing aid amplification were seen. This underlines the importance of considering perceived effort as a dimension when evaluating hearing aid benefit, in further research as well as in clinical practice. The results from the studies contribute to the knowledge about speech processing but also to the search for more specific evaluation of speech understanding, incorporating both sensory and cognitive factors.The ISBN 91-85297-49-6 in the printed verison is incorrect. The correct ISBN is 91-85297-93-3.</p

Swedish Dichotic Digits and Syllables

Sound recordings and other supplementary materials for Swedish Dichothic Speech Tests (Digits and Syllables) by Hällgren et al

The Swedish Hearing In Noise Test (HINT)

Sound recordings and other supplementary materials for the Swedish version of the Hearing In Noise Test (HINT

The role of cognitive abilities in younger and older normally hearing adults when listening to speech under adverse conditions

Cognitive abilities, such as working memory capacity (WMC), lexical decision making, and cognitive inhibition, can help predict performance on speech-recognition-in-noise tasks. Working memory is assumed to play a major part in every day listening situations, storing and actively working with relevant information, while inhibitory control helps to suppress and separate irrelevant information from interfering with the information processing. With increasing age, comes decreasing cognitive abilities, such as declines in WMC, speed of information processing, and inhibitory control, leading to problems when selectively attending to speech while inhibiting interfering distractors. The aim of the present study was to examine age-related declines in WMC, inhibitory control, and lexical decision making, and their respective roles when listening to speech under adverse listening conditions. Twenty-four young normally-hearing (NH), and 24 elderly ( for their age) NH individuals participated in the study. They completing a cognitive test battery assessing WMC, cognitive inhibition, and lexical decision making, as well as a closed-set (Hagerman sentences) and an open-set (HINT) speech-recognition-in-noise task masked with different maskers. We will present results comparing cognitive abilities in younger normally-hearing individuals with elderly normally-hearing individuals, and how age and cognitive abilities relates to performance on speech-recognition-in-noise tasks.Tal som störning vid språklig kommunikatio

Cognitive inhibition, WMC, and speech-recognition-in-noise

Cognitive abilities are important for a number of human attributes, such as making sense of communication, holding information active in memory, and making decisions. When it is the goal to focus on a single target voice, and resist intrusions from irrelevant information, cognitive inhibition can aid us in our endeavour. Cognitive inhibition is thought to support and co-operate with working memory. Abilities such as cognitive inhibition and working memory are also important for speech processing, even more so when listening to speech under adverse conditions. In order to assess different difficulties that can arise in every day listening situations, it´s of importance to have solid methods for measuring cognitive abilities. In the present study we present a task assessing cognitive inhibition, and how it relates to individual working memory capacity (WMC), and speech-recognition-in-noise. Forty-six young normally-hearing individuals were presented with a cognitive test battery, as well as a speech-in-noise test. Our results suggest that individuals with high WMC, also exhibit good cognitive inhibition. The results also indicate that those who perform well in the cognitive inhibition task need less favourable signal-to-noise-ratios in the speech-recognition task. Our findings indicate that capacity to resist semantic interference can be used to predict performance in speech-recognition tasks when listening under adverse conditions. Tal som störning vid språklig kommunikatio

Gated auditory speech perception in elderly hearing aid users and elderly normal-hearing individuals : effects of hearing impairment and cognitive capacity

This study compared elderly hearing aid (EHA) users and elderly normal-hearing (ENH) individuals on identification of auditory speech stimuli (consonants, words, and final word in sentences) that were different when considering their linguistic properties. We measured the accuracy with which the target speech stimuli were identified, as well as the isolation points (IPs: the shortest duration, from onset, required to correctly identify the speech target). The relationships between working memory capacity, the IPs, and speech accuracy were also measured. Twenty-four EHA users (with mild to moderate hearing impairment) and 24 ENH individuals participated in the present study. Despite the use of their regular hearing aids, the EHA users had delayed IPs and were less accurate in identifying consonants and words compared with the ENH individuals. The EHA users also had delayed IPs for final word identification in sentences with lower predictability; however, no significant between-group difference in accuracy was observed. Finally, there were no significant between-group differences in terms of IPs or accuracy for final word identification in highly predictable sentences. Our results also showed that, among EHA users, greater working memory capacity was associated with earlier IPs and improved accuracy in consonant and word identification. Together, our findings demonstrate that the gated speech perception ability of EHA users was not at the level of ENH individuals, in terms of IPs and accuracy. In addition, gated speech perception was more cognitively demanding for EHA users than for ENH individuals in the absence of semantic context

the Speech recognition under adverse listening conditions in young normally-hearing listeners

In the present study we aimed to investigate individual differences in cognitive inhibition, WMC, and how they relate to performance on a speech-recognition-in-noise task. Sixteen young normally-hearing individuals were presented with a cognitive test battery, as well as a sentence corpus masked by 5 different maskers, targeting 80% speech-recognition. One masker was a slightly modulated (10%) speech-shaped noise (SSN), 2 maskers were constructed by modulating the SSN with the envelopes from a single female talker, and the international speech test signal (ISTS). We also masked the target sentences with the ISTS, and a single female talker reading a passage in a Swedish newspaper. Our results showed that cognitive inhibition is significantly related to performance when maskers with meaningful, semantic information is used. The results further indicate that young normally-hearing individuals can take advantage of temporal and spectral dips to fill in missing information. Our findings suggest that choice of speech material is of importance for the outcome in speech-recognition-in-noise tasks. We further propose that tasks of cognitive inhibition can be used to predict performance in a speech-recognition task.Tal som störning vid språklig kommunikatio

Subjective ratings of masker disturbance during the perception of native and non-native speech

The aim of the present study was to address how 43 normal-hearing (NH) and hearing-impaired (HI) listeners subjectively experienced the disturbance generated by four masker conditions (i.e., stationary noise, fluctuating noise, Swedish two-talker babble and English two-talker babble) while listening to speech in two target languages, i.e., Swedish (native) or English (non-native). The participants were asked to evaluate their noise-disturbance experience on a continuous scale from 0 to 10 immediately after having performed each listening condition. The data demonstrated a three-way interaction effect between target language, masker condition, and group (HI versus NH). The HI listeners experienced the Swedish-babble masker as significantly more disturbing for the native target language (Swedish) than for the non-native language (English). Additionally, this masker was significantly more disturbing than each of the other masker types during the perception of Swedish target speech. The NH listeners, on the other hand, indicated that the Swedish speech-masker was more disturbing than the stationary and the fluctuating noise-maskers for the perception of English target speech. The NH listeners perceived more disturbance from the speech maskers than the noise maskers. The HI listeners did not perceive the speech maskers as generally more disturbing than the noise maskers. However, they had particular difficulty with the perception of native speech masked by native babble, a common condition in daily-life listening conditions. These results suggest that the characteristics of the different maskers applied in the current study seem to affect the perceived disturbance differently in HI and NH listeners. There was no general difference in the perceived disturbance across conditions between the HI listeners and the NH listeners

Учебная программа по учебной дисциплине "Введение в специальность"

Учебная программа "Введение в специальность" кафедры "Металлургия и технологии обработки материалов" для дневной формы получения образования: общее количество часов-30, форма контроля знаний — зачет