The effect of speech and speech intelligibility on task performance

Auditory imagery ability influences accuracy when singing with altered auditory feedback

In this preliminary study, we explored the relationship between auditory imagery ability and the maintenance of tonal and temporal accuracy when singing and audiating with altered auditory feedback (AAF). Actively performing participants sang and audiated (sang mentally but not aloud) a self-selected piece in AAF conditions, including upward pitch-shifts and delayed auditory feedback (DAF), and with speech distraction. Participants with higher self-reported scores on the Bucknell Auditory Imagery Scale (BAIS) produced a tonal reference that was less disrupted by pitch shifts and speech distraction than musicians with lower scores. However, there was no observed effect of BAIS score on temporal deviation when singing with DAF. Auditory imagery ability was not related to the experience of having studied music theory formally, but was significantly related to the experience of performing. The significant effect of auditory imagery ability on tonal reference deviation remained even after partialling out the effect of experience of performing. The results indicate that auditory imagery ability plays a key role in maintaining an internal tonal center during singing but has at most a weak effect on temporal consistency. In this article, we outline future directions in understanding the multifaceted role of auditory imagery ability in singers' accuracy and expression.

The effect of font boldness, noise disturbance and time pressure on human error in the context of cloud change operation

This study investigated the number of operator errors, task completion time, and workload of subjects at different levels by imposing conditions such as focused text boldness, noise disturbance, and time pressure to simulate a realistic cloud change business process in the laboratory. Results of the study showed that the text bolding of important content reduced the number of errors, whereas noise interference increased the number of errors. Text boldness only reduced the number of corrected errors, and noise interference only increased the number of uncorrected errors. Moreover, bolding was found to have different effects on the number of errors under different noise levels and time pressure levels, with text boldness significantly reducing the number of total errors only in quiet or low time pressure states. Time pressure had no effect on cloud change task error counts, but high time pressure resulted in higher subjective workload.

University Library Space Renovation Based on the User Learning Experience in Two Wuhan Universities

University library spaces play an important role in the learning experience of students. However, the traditional designs for these learning spaces no longer meet the needs of users, and researchers have been turning their attention to university library space renovation. By combing existing theories and practices, this study determined a framework of six university library space renovation design principles and subsequently conducted a survey to examine university library space user learning experience in two university libraries in Wuhan, China. Data analysis was conducted using SPSS. From the questionnaire-based survey results, this study determined seven design elements that affect the learning experience of university library users. The results of binary logistic regression showed that two elements, indoor physical space comfort and indoor acoustic environment comfort, have positive effects on the frequency and length of visits to the library. Key spatial elements that can promote library space users' learning experience were also identified, thus providing data that can reliably inform future design strategies for the space renovation of university libraries.

Effects of Auditory Pre-Stimulation on Cognitive Task Performance in a Noisy Environment

The accident rate due to human errors in industrial fields has been consistently high over the past few decades, and noise has been emerging as one of the main causes of human errors. In recent years, auditory pre-stimulation has been considered as a means of preventing human errors by improving workers’ cognitive task performance. However, most previous studies demonstrated the effectiveness of the auditory pre-stimulation in a quiet environment. Accordingly, studies on the effects of pre-stimulation in a noisy environment are still lacking. Therefore, this study aimed to empirically investigate: (1) the effects of noisy environments on the performances of cognitive tasks related to different functions of working memory and (2) the effects of auditory pre-stimulation on the performances of cognitive tasks in a field-noise environment. To accomplish these research objectives, two major experiments were conducted. In the first experiment, a total of 24 participants performed each of three basic short-term/working memory (STM/WM) tasks under two different experimental conditions (quiet-noise environment and field-noise environment) depending on the presence or absence of field noise. In the second experiment, the participants performed each of the three basic STM/WM tasks in a field-noise environment after they were provided with one of four different auditory pre-stimulations (quiet noise, white noise, field noise, and mixed (white and field) noise). The three STM/WM tasks were the Corsi block-tapping, Digit span, and 3-back tasks, corresponding to the visuospatial sketchpad, the phonological loop, and the central executive of WM, respectively. The major findings were that: (1) the field-noise environment did not affect the scores of the Corsi block-tapping and 3-back tasks, significantly affecting only the Digit span task score (decreased by 15.2%, p < 0.01); and (2) the Digit span task performance in the field-noise environment was improved by 17.9% (p < 0.05) when mixed noise was provided as a type of auditory pre-stimulation. These findings may be useful for the work-space designs that prevent/minimize human errors and industrial accidents by improving the cognitive task performance of workers in field-noise environments.

Spectral content (colour) of noise exposure affects work efficiency

Introduction:

As part of an effort to enhance the efficiency of workers, experiments relating to three types of noise exposure were conducted. Previous studies have proved that pink noise can cause a brain wave to reach a lower potential. In this study, we utilized physical methods, in cognitive experiments, to understand the impacts that three colour noises have on working efficiency.

Subjects and Methods:

All 22 participants were exposed to a sound environment of quiet, red, pink and white noises respectively. After a laboratory experiment, details of psychomotor speed, continuous performance, executive function and working memory were recorded.

Results:

Red, pink and white noises were significantly positive in comparison with the quiet environment of the psychomotor speed test. As for the continuous performance test, pink noise gave the only significantly positive result. Red, pink and white noise resulted in a better executive function test. Red and pink noise showed significantly positive improvement, while white noise was significantly positive in comparison with the quiet environment of the working memory test. In addition, the results from the comfort questionnaires showed that red and pink noise increase the possibility of better judgment, implementation, and overall environment.

Conclusion:

At present time, it is considered that noise has negative effects on hearing and health. However, experimental results show that certain noise can enhance environmental comfort. It is feasible, in the future, to use knowledge of colour noises to improve productivity in a workplace with a healthy environment.

Open-plan office noise is stressful: multimodal stress detection in a simulated work environment

The coronavirus disease 2019 (COVID-2019)-induced changes in the workplace present a timely opportunity for human resource management practitioners to consider and remediate the deleterious effects of noise, a commonly cited complaint of employees working in open-plan office (OPO) environments. While self-reports suggest that OPO noise is perceived as a stressor, there is little experimental research comprehensively investigating the effects of noise on employees in terms of their cognitive performance, physiological indicators of stress, and affect. Employing a simulated office setting, we compared the effects of a typical OPO auditory environment to a quieter private office auditory environment on a range of objective and subjective measures of well-being and performance. While OPO noise did not reduce immediate cognitive task performance compared to the quieter environment, it did reduce psychological well-being as evidenced by self-reports of mood, facial expressions of emotion, and physiological indicators of stress in the form of heartrate and skin conductivity. Our research highlights the importance of using a multimodal approach to assess the impact of workplace stressors such as noise. Such an approach will allow HR practitioners to make data-driven recommendations about the design and modification of workspaces to minimize negative effects and support employee well-being.

Speech is special: The stress effects of speech, noise, and silence during tasks requiring concentration

Effects of noise on people depend on sound level but also on other sound properties. A systematic comparison of the stress effects of speech and noise with the same frequency content is missing. This study compared stress reactions under sound conditions speech (sound level 65 dB L_Aeq ), noise (65 dB), and silence (35 dB), all having similar relative frequency contents. Fifty-nine participants were exposed to one out of three sound conditions on average for 48 minutes while performing tasks requiring concentration. Acute physiological stress was estimated by measuring stress hormone concentrations in plasma (cortisol and noradrenaline), heart rate variability (HRV), and blood pressure. Psychological stress measures were subjective noise annoyance, workload, and fatigue. Compared to silence and noise, working during speech was more annoying, loading, but less tiring, and led to elevated HRV LF/HF ratio with time. Speech also raised cortisol levels compared with silence. Although noise was more annoying, and raised cortisol levels compared with silence, working during speech was more loading and caused more physiological stress than other sound conditions. Special care should be paid to noise control in workplaces requiring concentration because already exposure to moderate sound level sounds caused clear physiological effects on people.

Objective measures of cognitive performance in activity based workplaces and traditional office types

Distraction from the background environment while performing concentrationdemanding tasks is a common issue for office employees in shared work areas. However, few field studies have been conducted on the effects of different office types and work areas on objective measurements of cognitive performance. The first aim of the present field study was to investigate, before relocation to an activity-based workplace (ABW), differences in performance on a concentration-demanding cognitive task between individuals in shared/open-plan offices compared to cell offices. The second aim was to investigate, after relocation, how performance differs (withinperson) between different work areas within the ABW. This study included employees from five offices (n = 113), of which four relocated into an ABW. An acoustician measured the equivalent sound levels of the work areas. Data were analyzed using linear regression (aim 1) and mixed models (aim 2). Before relocation, employees working in shared/open-plan offices performed significantly worse (14%) than those in cell-offices, which had a 15 LAeq lower noise level. After relocation, employees performed significantly worse in the active zone without noise restrictions, compared to all other work areas. When shifting open-plan area from the active zone to the quiet zone cognitive performance increased significantly by 16.9%, and switching to individual working rooms increased performance by 21.9%. The results clearly demonstrate the importance for organizations to provide quiet areas or rooms with few distractions for employees working on tasks that demand concentration in an ABW. A daily drop in performance for each employee may be expensive for the organization in the long run.

The relation between the intelligibility of irrelevant speech and cognitive performance-A revised model based on laboratory studies

Irrelevant background speech causes dissatisfaction and impairs cognitive performance in open-plan offices. The model of Hongisto (2005, Indoor Air, 15, 458-468) predicts the relation between cognitive performance and the intelligibility of speech described with an objectively measured quantity, the Speech Transmission Index (STI). The model has impacted research in psychology and room acoustics as well as the acoustic design guidelines of offices. However, the model was based on scarce empirical data. The aim of this study was to revise the model based on a systematic literature review, focusing on laboratory experiments manipulating the STI of speech by wide-band steady-state noise. Fourteen studies reporting altogether 34 tests of the STI-performance relation were included. According to Model 1 that includes all tests, performance begins to decrease approximately above STI = 0.21 while the maximum decrease is reached at STI = 0.44. Verbal short-term memory tasks were most strongly and very consistently affected by the STI of speech. The model for these tasks showed a deterioration in performance between STI 0.12 and 0.51. Some evidence of an STI-performance relation was found in verbal working memory tasks and limited evidence in complex verbal tasks. Further research is warranted, particularly concerning task-specific effects.

Coping strategies and perceived productivity in open-plan offices with noise problems

Purpose

To study effects of different sources of noise in office environments on perceived productivity, how different types of employees cope with different noise sources, and the perceived effect of different coping strategies on individual productivity.

Design/methodology/approach

Data on coping behavior and noise perception was collected through a survey among 150 employees of 3 organizations with an office in the Netherlands. These were analyzed with X2-tests and the lift-ratio.

Findings

When coping with noise, people are most inclined to either “Make even a greater effort” or “Discuss the noise problem with colleagues,” despite the expectation that this does not have a major positive effect on their productivity. Overall, approach coping strategies were chosen less often than the avoidance coping strategies. There are clear preferences for specific coping strategies when exposed to specific noise sources. Personal differences did not appear to relate to the perception of noise sources but did show differences in coping behavior as well.

Originality/value

This study adds insights about preferred coping strategies for specific noise sources, differences in these preferences related to specific personal characteristics, and how successful these strategies are perceived to be with regard to support of individual productivity.

Designing healthy workspaces: results from Australian certified open-plan offices

Purpose

From poor indoor environmental quality conditions to musculoskeletal discomfort, the interior design of workspaces has the potential to negatively affect human health. One of the key responses from industry has been the rise of health-related guidelines, certification and rating tools. Despite the rapid adoption of such tools by the Australian high-end corporate real estate, there is a scarcity of empirical evidence arising from such premises. This study aims to compare results from certified premises against other open-plan offices to understand differences arising from occupants’ satisfaction, perceived productivity and health.

Design/methodology/approach

A total of 1,121 post-occupancy evaluation (POE) surveys conducted in 9 offices were analyzed. All these premises hold a certification from the Green Building Council of Australia and two achieved a WELL rating. The analysis is performed in three parts: comparing WELL-certified (2 cases) and non-WELL certified (7 cases) offices along with comparison with a benchmark of 9,794 POE surveys from the BOSSA database, comparing activity-based working (ABW) (5 cases) and traditional (4 cases) offices along with comparison with BOSSA database and qualitative study of the similar design features in all 9 offices accompanied with an in-depth analysis of the health-related issues that might have occurred because of poor ergonomic design. For the first two parts, several t-tests are performed.

Findings

Highest scores for overall satisfaction, workability, perceived productivity and health were reported on WELL-rated premises. Offices incorporating active design principles outperformed others on workability, satisfaction with work area, collaboration, unwanted interruptions, perceived productivity and health. ABW environments outperformed the traditional offices on spatial comfort, thermal comfort, noise and privacy, personal control, comfort of furnishing, adjustability of the work area and space to collaborate. People using sit–stand workstations reported spending significantly less time seated and female workers were more prone to reporting pain over the past 12 months. The best-performing offices implemented active and biophilic design, prioritized overall ergonomics and different spaces designed to support a variety of work-related activities.

Originality/value

This research conducts a comparison between certified premises against other offices in terms of occupants’ satisfaction, perceived productivity and health. A qualitative analysis is also conducted to investigate personal and physical environmental aspects. The way of working (ABW or traditional), implementation of active design features, self-reported musculoskeletal discomfort and physical activity were also investigated. The study has taken a holistic approach to investigate many health-related physical, environmental and emotional aspects in certified workspaces.

Audio-visual preferences, perception, and use of water features in open-plan offices

This paper examines the use of water features for masking irrelevant speech and improving the soundscape of open-plan offices. Two laboratory experiments were carried out, as well as acoustic simulations and field tests. Experiment 1 aimed to identify the preferred sound level of water sounds against irrelevant speech. Experiment 2 examined the audio-only and audio-visual preferences and perception of waterscapes. Acoustic simulations and field tests examined the impact of design factors. The results showed that, when played against a constant level of irrelevant speech of 48 dBA, people prefer to listen to water sounds of 42-48 dBA (45 dBA being best). These results and results from previous research suggest that water sounds work mainly as informational maskers rather than energetic maskers. Furthermore, the introduction of a water feature improved the perception of the sound environment, and adding visual stimuli improved perception by up to 2.5 times. Acoustic simulations indicated that features at each corner and one at the center (or a single feature with an array of speakers) can provide appropriate masking for a large open-plan office, whilst field tests showed that water sounds decrease the distraction and privacy distances significantly (clusters of workstations benefitting more than rows of workstations).

Effects of a cognitive ergonomics workplace intervention (CogErg) on cognitive strain and well-being: a cluster-randomized controlled trial. A study protocol

Background

Cognitively straining conditions such as disruptions, interruptions, and information overload are related to impaired task performance and diminished well-being at work. It is therefore essential that we reduce their harmful consequences to individual employees and organizations. Our intervention study implements practices for managing the cognitive strain typical to office work tasks and working conditions in offices. We will examine the effects of a cognitive ergonomics intervention on working conditions, workflow, well-being, and productivity.

Methods/design

The study is a stratified cluster randomized trial. The clusters are work units, for example, teams or offices. The four participating organizations entered a total of 36 clusters, and we invited all 1169 knowledge employees of these units to participate. We randomly allocated the clusters into an intervention group (cognitive ergonomics) or an active control group (recovery supporting). We invited an additional 471 participants to join a passive control group only for baseline and follow-up measurements, with no intervention.

The study consists of a baseline survey and interviews and observations at the workplace, followed by an intervention. It starts with a workshop defining the specific actions for the intervention implementation stage, during which we send task reminder questionnaires to all employees to support behaviour change at the individual and team levels. The primary outcome measure is perceived frequency of cognitive strain from working conditions; the secondary outcome measures include subjective cognitive load, well-being, workflow/productivity, and cognitive stress symptoms. Process evaluation uses the quantitative and qualitative data obtained during the implementation and evaluation phases. The baseline measurements, intervention phase, and end-of-treatment measurements are now complete, and follow-up will continue until November 2019.

Discussion

There is a need to expand the research of cognitive strain, which poses a considerable risk to work performance and employee well-being in cognitively demanding tasks. Our study will provide new information about factors that contribute to such strain. Most importantly, the results will show which evidence-based cognitive ergonomic practices support work performance in knowledge work, and the project will provide concrete examples of how to improve at work.

Trial registration

ClinicalTrials.gov, NCT03573674. Registered 29 June 2018.

The effects of speech intelligibility on English scientific literature reading in Chinese open-plan offices

A laboratory experiment was conducted to study the effects of speech intelligibility on English scientific literature reading performance in Chinese open-plan offices (both the occupants' native language and ambient speech noise were Chinese). The objective performance and subject perceptions of 20 participants were tested under different speech intelligibility conditions. The results highlight the significant negative impact of speech noise on occupants' performance. Moreover, a comparison of these results and those of previous studies implies Chinese occupants engaged in English scientific literature reading tasks are more sensitive to the changes of speech intelligibility and have higher requirements for acoustic environment.

The Rise of Office Design in High-Performance, Open-Plan Environments

This study aimed to identify key drivers behind workers’ satisfaction, perceived productivity, and health in open-plan offices while at the same time understanding design similarities shared by high-performance workspaces. Results from a dataset comprising a total of 8827 post-occupancy evaluation (POE) surveys conducted in 61 offices in Australia and a detailed analysis of a subset of 18 workspaces (n = 1949) are reported here. Combined, the database-level enquiry and the subset analysis helped identifying critical physical environment-related features with the highest correlation scores for perceived productivity, health, and overall comfort of the work area. Dataset-level analysis revealed large-size associations with spatial comfort, indoor air quality, building image and maintenance, noise distraction and privacy, visual comfort, personal control, and connection to the outdoor environment. All high-performance, open-plan offices presented a human-centered approach to interior design, purposely allocated spaces to support a variety of work-related tasks, and implemented biophilic design principles. These findings point to the importance of interior design in high-performance workspaces, especially in relation to open-plan offices.

Noise Indicators for Size Distributions of Airborne Particles and Traffic Activities in Urban Areas

The aim of this study was to explore the relationships among the particle number concentration (PNC), noise, and traffic conditions. Field measurements were conducted to measure the temporal variabilities of the noise levels and PNC over 24 h in a location adjacent to three main traffic roads in Seoul, Korea. The PNC was measured in the range of 0.3 to 10 µm. The noise data was measured by utilizing both the overall levels and spectral characteristics. Traffic data including volumes and speeds of vehicles on the roads were also collected. The results showed that the correlations among the three key parameters varied depending on changes in the noise frequency and particle size. The noise levels at 100–200 Hz were positively correlated with traffic volume and submicron particles. In contrast, they exhibited inverse correlations with the traffic speed and the number of larger particles (>2.5 µm). Compared to noise levels at 100–200 Hz, noise levels at 1–2 kHz exhibited reverse relationships between the traffic and PNC. Submicron particles (0.3–1.0 µm) tended to be more strongly associated with noise levels during the daytime, while those greater than 2.5 µm maintained relatively stable correlations with the noise throughout the day. The findings address the importance of temporal and spectral-specific monitoring of air and noise pollutants for a better understanding of the exposure of the community to air and noise pollution.

Auditory Distraction During Reading: A Bayesian Meta-Analysis of a Continuing Controversy

Everyday reading occurs in different settings, such as on the train to work, in a busy cafeteria, or at home while listening to music. In these situations, readers are exposed to external auditory stimulation from nearby noise, speech, or music that may distract them from their task and reduce their comprehension. Although many studies have investigated auditory-distraction effects during reading, the results have proved to be inconsistent and sometimes even contradictory. In addition, the broader theoretical implications of the findings have not always been explicitly considered. We report a Bayesian meta-analysis of 65 studies on auditory-distraction effects during reading and use metaregression models to test predictions derived from existing theories. The results showed that background noise, speech, and music all have a small but reliably detrimental effect on reading performance. The degree of disruption in reading comprehension did not generally differ between adults and children. Intelligible speech and lyrical music resulted in the biggest distraction. Although this last result is consistent with theories of semantic distraction, there was also reliable distraction by noise. It is argued that new theoretical models are needed that can account for distraction by both background speech and noise.

The impact of different background noises on the Production Effect

The presence of background noise has been previously shown to disrupt cognitive performance, especially memory. The amount of interference is derived from the acoustic characteristics of the noise; energetic vs. informational, steady-state vs. fluctuating. However, the literature is inconsistent concerning the effects of different types of noise on long-term memory free recall. In the present study, we tested the impact of different noises on recall of items that were learned under two conditions - silent or aloud reading, a Production Effect (PE) paradigm. As the PE represents enhanced memory for words read aloud relative to words read silently during study, we focused on the effect of noise on this robust memory phenomenon. The results showed that (a) steady-state energetic noise did not affect memory, with a recall advantage for aloud words (PE), comparable to a no-noise condition, (b) fluctuating-energetic noise and fluctuating-informational (eight-talkers babble) noise eliminated the PE, with similar recall for aloud and silent items. These results are discussed in light of their theoretical implications, stressing the role of attention in the PE. Ecological implications regarding studying in noisy environments are suggested.

Perception of Water-Based Masking Sounds-Long-Term Experiment in an Open-Plan Office

A certain level of masking sound is necessary to control the disturbance caused by speech sounds in open-plan offices. The sound is usually provided with evenly distributed loudspeakers. Pseudo-random noise is often used as a source of artificial sound masking (PRMS). A recent laboratory experiment suggested that water-based masking sound (WBMS) could be more favorable than PRMS. The purpose of our study was to determine how the employees perceived different WBMSs compared to PRMS. The experiment was conducted in an open-plan office of 77 employees who had been accustomed to work under PRMS (44 dB L_Aeq). The experiment consisted of five masking conditions: the original PRMS, four different WBMSs and return to the original PRMS. The exposure time of each condition was 3 weeks. The noise level was nearly equal between the conditions (43–45 dB L_Aeq) but the spectra and the nature of the sounds were very different. A questionnaire was completed at the end of each condition. Acoustic satisfaction was worse during the WBMSs than during the PRMS. The disturbance caused by three out of four WBMSs was larger than that of PRMS. Several attributes describing the sound quality itself were in favor of PRMS. Colleagues' speech sounds disturbed more during WBMSs. None of the WBMSs produced better subjective ratings than PRMS. Although the first WBMS was equal with the PRMS for several variables, the overall results cannot be seen to support the use of WBMSs in office workplaces. Because the experiment suffered from some methodological weaknesses, conclusions about the adequacy of WBMSs cannot yet be drawn.

Effects of Task Interruption and Background Speech on Word Processed Writing

Task interruptions and background speech, both part of the everyday situation in office environments, impair cognitive performance. The current experiments explored the combined effects of background speech and task interruptions on word processed writing—arguably, a task representative of office work. Participants wrote stories, in silence or in the presence of background speech (monologues, halfalogues and dialogues), and were occasionally interrupted by a secondary task. Writing speed was comparably low during the immediate period after the interruption (Experiments 1 and 2); it took 10–15 s to regain full writing speed. Background speech had only a small effect on performance (Experiment 1), but a dialogue was more disruptive than a halfalogue (Experiment 2). Background speech did not add to the cost caused by task interruptions. However, subjective measures suggested that speech, just as interruptions, contributed to perceived workload. The findings are discussed in view of attentional capture and interference‐by‐process mechanisms.© 2016 The Authors. Applied Cognitive Psychology published by John Wiley & Sons, Ltd.

Distracted While Reading? Changing to a Hard-to-Read Font Shields against the Effects of Environmental Noise and Speech on Text Memory

The purpose of this study was to investigate the distractive effects of background speech, aircraft noise and road traffic noise on text memory and particularly to examine if displaying the texts in a hard-to-read font can shield against the detrimental effects of these types of background sounds. This issue was addressed in an experiment where 56 students read shorter texts about different classes of fictitious creatures (i.e., animals, fishes, birds, and dinosaurs) against a background of the aforementioned background sounds respectively and silence. For half of the participants the texts were displayed in an easy-to-read font (i.e., Times New Roman) and for the other half in a hard-to-read font (i.e., Haettenschweiler). The dependent measure was the proportion correct answers on the multiple-choice tests that followed each sound condition. Participants’ performance in the easy-to-read font condition was significantly impaired by all three background sound conditions compared to silence. In contrast, there were no effects of the three background sound conditions compared to silence in the hard-to-read font condition. These results suggest that an increase in task demand—by displaying the text in a hard-to-read font—shields against various types of distracting background sounds by promoting a more steadfast locus-of-attention and by reducing the processing of background sound.

Background Speech Effects on Sentence Processing during Reading: An Eye Movement Study

Effects of background speech on reading were examined by playing aloud different types of background speech, while participants read long, syntactically complex and less complex sentences embedded in text. Readers’ eye movement patterns were used to study online sentence comprehension. Effects of background speech were primarily seen in rereading time. In Experiment 1, foreign-language background speech did not disrupt sentence processing. Experiment 2 demonstrated robust disruption in reading as a result of semantically and syntactically anomalous scrambled background speech preserving normal sentence-like intonation. Scrambled speech that was constructed from the text to-be read did not disrupt reading more than scrambled speech constructed from a different, semantically unrelated text. Experiment 3 showed that scrambled speech exacerbated the syntactic complexity effect more than coherent background speech, which also interfered with reading. Experiment 4 demonstrated that both semantically and syntactically anomalous speech produced no more disruption in reading than semantically anomalous but syntactically correct background speech. The pattern of results is best explained by a semantic account that stresses the importance of similarity in semantic processing, but not similarity in semantic content, between the reading task and background speech.

Musculoskeletal Symptoms and Risk of Burnout in Child Care Workers - A Cross-Sectional Study

Objectives

German child care workers' job satisfaction is influenced by the consequences of unfavourable underlying conditions. Child care workers tend to suffer from psychosocial stress, as they feel that their work is undervalued. The objective of the present study is to investigate how the psychosocial factors of the effort-reward imbalance (ERI) model influence musculoskeletal symptoms (MS) and the risk of burnout. To our knowledge this is the first study investigating the association between the factors of the ERI model and MS in child care workers.

Methods and Findings

Data from 199 child care workers were examined in a cross-sectional study. Psychosocial factors were recorded with the ERI questionnaire. MS was recorded with the Nordic Questionnaire and risk of burnout with the Personal Burnout scale of the Copenhagen Burnout Inventory. Multivariate analysis was performed using linear and logistic regression models. The response rate was 57%. In most of the sample (65%), an effort-reward imbalance was observed. 56% of the child care workers were at risk of burnout and 58% reported MS. Factors associated with risk of burnout were subjective noise exposure (OR: 4.4, 95%CI: 1.55–12.29) and overcommitment (OR: 3.4; 95%CI: 1.46–7.75). There were statistically significant associations between MS and overcommitment (low back pain—OR: 2.2, 95%CI: 1.04–4.51), low control (overall MS OR: 3.8; 95%CI: 1.68–3.37) and risk of burnout (overall MS OR: 2.3, 95%CI: 1.01–5.28). For ERI no statistically significant associations were found with reference to risk of burnout or MS.

Conclusion

Overcommitment in child care workers is related to MS and risk of burnout. There is also evidence that low control is associated with MS and subjective noise exposure with risk of burnout. Effort-reward imbalance is not related to either outcome. This occupational health risk assessment identifies changeable working factors in different types of facilities.

Unmasking the effects of masking on performance: The potential of multiple-voice masking in the office environment

Broadband noise is often used as a masking sound to combat the negative consequences of background speech on performance in open-plan offices. As office workers generally dislike broadband noise, it is important to find alternatives that are more appreciated while being at least not less effective. The purpose of experiment 1 was to compare broadband noise with two alternatives-multiple voices and water waves-in the context of a serial short-term memory task. A single voice impaired memory in comparison with silence, but when the single voice was masked with multiple voices, performance was on level with silence. Experiment 2 explored the benefits of multiple-voice masking in more detail (by comparing one voice, three voices, five voices, and seven voices) in the context of word processed writing (arguably a more office-relevant task). Performance (i.e., writing fluency) increased linearly from worst performance in the one-voice condition to best performance in the seven-voice condition. Psychological mechanisms underpinning these effects are discussed.

On interpretation and task selection: the sub-component hypothesis of cognitive noise effects

It is often argued that the effects of noise on a “complex ability” (e.g., reading, writing, calculation) can be explained by the impairment noise causes to some ability (e.g., working memory) upon which the complex ability depends. Because of this, tasks that measure “sub-component abilities” (i.e., those abilities upon which complex abilities depend) are often deemed sufficient in cognitive noise studies, even when the primary interest is to understand the effects of noise as they arise in applied settings (e.g., offices and schools). This approach can be called the “sub-component hypothesis of cognitive noise effects.” The present paper discusses two things that are troublesome for this approach: difficulties with interpretation and generalizability. A complete understanding of the effects of noise on complex abilities requires studying the complex ability itself. Cognitive noise researches must, therefore, employ tasks that mimic the tasks that are actually carried out in the applied setting to which the results are intended to be generalized. Tasks that measure “sub-component abilities” may be complementary, but should not be given priority in applied cognitive research.

The effects of intelligible irrelevant background speech in offices – cognitive disturbance, annoyance, and solutions

Purpose

– This paper aims to give an overview on four empirical studies which explored the impact of background speech on cognitive performance and subjectively perceived disturbance. Background speech is the most serious noise problem in shared-room and open-plan offices for employees who are supposed to do silent, concentrated work. Different measures of acoustic office optimization, as well as the outstanding role of the intelligibility of background speech for its disturbance impact, are empirically evaluated.

Design/methodology/approach

– The article provides a synopsis describing the core empirical results of four of our empirical studies. A survey study among office employees (n = 659) explored the subjective importance of office acoustics. Three experimental studies (n1 = 20; n2 = 30; n3 = 24) evaluated the effects of reduced background speech level, play-back of partial maskers and reduced speech intelligibility on cognitive performance and subjective ratings.

Findings

– Background speech is subjectively perceived as a severe problem, and the different noise abatement measures affect objective performance and subjective ratings differently. Speech intelligibility is – besides level – a key determinant for the acoustic optimization regarding these two dimensions.

Research limitations/implications

– Practitioners are encouraged to apply the findings and described measures when planning and/or evaluating open-plan offices.

Practical implications

– It is concluded that different acoustically efficient measures need to be combined to minimize the negative effects of background speech on cognitive performance and subjectively perceived disturbance. The aspired set value for open-office concepts is the lowest possible sound level with a bad intelligibility of the background speech at the same time.

Originality/value

– The synopsis of several empirical studies allows deriving comprehensive and well-founded information for practitioners involved in the evaluation and/or design of offices environments.

On interpretation and task selection in studies on the effects of noise on cognitive performance

THIS PAPER DISCUSSES TWO THINGS RESEARCHERS SHOULD CONSIDER WHEN SELECTING TASKS FOR COGNITIVE NOISE STUDIES AND INTERPRETING THEIR FINDINGS: (a) The "process impurity" problem and (b) the propensity of sound to capture attention. Theoretical and methodological problems arise when the effects of noise on complex tasks (e.g., reading comprehension) are interpreted as reflecting an impairment of a specific cognitive process/system/skill. One reason for this is that complex tasks are, by definition, process impure (i.e., they involve several, distinct cognitive processes/systems/skills). Another reason is that sound can capture attention. When sound captures attention, the impairment to task scores is caused by an interruption, not by malfunctioning cognitive processes/systems/skills. Selecting more "process pure" tasks (e.g., the Stroop task) is not a solution to these problems. On the contrary, it introduces further problems with generalizability and representativeness. It is argued that cognitive noise researchers should employ representative noise, representative tasks (which are necessarily complex/process impure), and interpret the results on a behavioral level of analysis rather than on a cognitive level of analysis.

Improving speech-in-noise recognition for children with hearing loss: potential effects of language abilities, binaural summation, and head shadow

OBJECTIVE

This study examined speech recognition in noise for children with hearing loss, compared it to recognition for children with normal hearing, and examined mechanisms that might explain variance in children's abilities to recognize speech in noise.

DESIGN

Word recognition was measured in two levels of noise, both when the speech and noise were co-located in front and when the noise came separately from one side. Four mechanisms were examined as factors possibly explaining variance: vocabulary knowledge, sensitivity to phonological structure, binaural summation, and head shadow.

STUDY SAMPLE

Participants were 113 eight-year-old children. Forty-eight had normal hearing (NH) and 65 had hearing loss: 18 with hearing aids (HAs), 19 with one cochlear implant (CI), and 28 with two CIs.

RESULTS

Phonological sensitivity explained a significant amount of between-groups variance in speech-in-noise recognition. Little evidence of binaural summation was found. Head shadow was similar in magnitude for children with NH and with CIs, regardless of whether they wore one or two CIs. Children with HAs showed reduced head shadow effects.

CONCLUSION

These outcomes suggest that in order to improve speech-in-noise recognition for children with hearing loss, intervention needs to be comprehensive, focusing on both language abilities and auditory mechanisms.

Combined effects of acoustic and visual distraction on cognitive performance and well-being

Information work is usually performed in offices and influenced by the combined effects of acoustics, room climate, lighting and air quality. However, the principal part of literature solely focuses on the individual effects of physical parameters. This study (n = 32) investigates the combined effects of acoustic and visual distraction with regard to cognitive performance and well-being. Therefore low level background speech (40 dB(A)) of good or poor intelligibility was combined with either static or dynamic lighting. Experimental testing lasted for approx. 7 h for each participant and was conducted in mock-up offices. No interaction effects of background speech and lighting conditions with regard to cognitive performance were found. However, the results prove that even low level background speech of high intelligibility significantly impairs short-term memory, reasoning ability and well-being. But no effect of background speech on text comprehension and sustained attention was found. Visual distraction due to dynamic lighting caused significant complaints but did not impair performance. An interaction effect of background speech and lighting conditions was found with regard to perceived performance during task processing. Test persons only felt to perform better, if background speech of low intelligibility was combined with static lighting. It is shown that the effects on cognitive performance and well-being must be considered separately since these effects are rarely consistent.

Disruption of writing processes by the semanticity of background speech

Previous studies have noted that writing processes are impaired by task-irrelevant background sound. However, what makes sound distracting to writing processes has remained unaddressed. The experiment reported here investigated whether the semanticity of irrelevant speech contributes to disruption of writing processes beyond the acoustic properties of the sound. The participants wrote stories against a background of normal speech, spectrally-rotated speech (i.e., a meaningless sound with marked acoustic resemblance to speech) or silence. Normal speech impaired quantitative (e.g., number of characters produced) and qualitative/semantic (e.g., uncorrected typing errors, proposition generation) aspects of the written material, in comparison with the other two sound conditions, and it increased the duration of pauses between words. No difference was found between the silent and the rotated-speech condition. These results suggest that writing is susceptible to disruption from the semanticity of speech but not especially susceptible to disruption from the acoustic properties of speech.

Spoken word recognition in adolescent cochlear implant users during quiet and multispeaker babble conditions

OBJECTIVE

To assess overall speech intelligibility in adolescent cochlear implant speakers during quiet and multispeaker babble conditions.

STUDY DESIGN

A cross-sectional assessment of intelligibility incorporating group (auditory-oral versus total communication speakers), sentence context (high versus low contexts), and background conditions (quiet versus multispeaker babble).

SETTING

A camp designed to assess adolescents over a concentrated period.

PARTICIPANTS

Fifty-seven adolescents who participated in an earlier study when they were 8 to 9 years old examining functional outcomes of speech perception, speech production, and language were asked to participate in follow-up study.

METHODS

Speech intelligibility was assessed by asking the adolescents to repeat sentences. Sentences were digitally edited and played to normal hearing listeners who either provided broad transcriptions of sound accuracy or wrote down the words they understood when the sentences were presented in quiet and in multispeaker babble.

MAIN OUTCOME VARIABLE

The dependent variables were percent correct consonants, vowels, and total words identified.

RESULTS

Very few substitutions or omissions occurred, resulting in high levels of accuracy for consonants and vowels. Speech intelligibility in quiet was significantly greater than in the multispeaker babble condition. Multispeaker babble decreased performance uniformly across sentence context for the 2 groups.

CONCLUSION

Accurate consonant production based on measures of substitutions and omissions fails to account for distortions and allophonic variations. Reductions in speech intelligibility relative to the phoneme correct productions suggest that the allophonic variations related to distortions may influence naive listener's ability to understand the speech of profoundly deaf individuals.

Effects of white noise on Callsign Acquisition Test and Modified Rhyme Test scores

The Callsign Acquisition Test (CAT) is a speech intelligibility test developed by the US Army Research Laboratory. The test has been used to evaluate speech transmission through various communication systems but has not been yet sufficiently standardised and validated. The aim of this study was to compare CAT and Modified Rhyme Test (MRT) performance in the presence of white noise across a range of signal-to-noise ratios (SNRs). A group of 16 normal-hearing listeners participated in the study. The speech items were presented at 65 dB(A) in the background of white noise at SNRs of -18, -15, -12, -9 and -6 dB. The results showed a strong positive association (75.14%) between the two tests, but significant differences between the CAT and MRT absolute scores in the range of investigated SNRs. Based on the data, a function to predict CAT scores based on existing MRT scores and vice versa was formulated. STATEMENT OF RELEVANCE: This work compares performance data of a common speech intelligibility test (MRT) with a new test (CAT) in the presence of white noise. The results here can be used as a part of the standardisation procedures and provide insights to the predictive capabilities of the CAT to quantify speech intelligibility communication in high-noise military environments.

Performance effects and subjective disturbance of speech in acoustically different office types--a laboratory experiment

This study examined how the intelligibility of irrelevant speech, determined with the Speech Transmission Index (STI), affects demanding cognitive task performance. Experiment was carried out in a laboratory that resembled an open-plan office. Three speech conditions were tested corresponding to a private office (STI = 0.10), an acoustically excellent open office (STI = 0.35) and an acoustically poor open office (STI = 0.65). All conditions were presented at equal level, 48 dBA. The STI was adjusted by the relative levels of speech and masking sound. Thirty-seven students participated in the experiment that lasted for 4 h. All participants performed five tasks in each of the three speech conditions. Questionnaires were used to assess subjective perceptions of the speech conditions. Performance in the operation span task, the serial recall and the activation of prior knowledge from long-term memory were deteriorated in the speech condition with the highest speech intelligibility (STI = 0.65) in comparison with the other two conditions (STI = 0.10 and STI = 0.35). Unlike performance measures, questionnaire results showed consistent differences among all three speech conditions, i.e. subjective disturbance increased with ascending speech intelligibility. Thus, subjective comfort was disturbed more easily than performance. The results support the use of STI as an essential room acoustic design measure in open-plan offices.

PRACTICAL IMPLICATIONS

Reduction of speech intelligibility in office environments by proper acoustic design would be beneficial in terms of both work performance and subjective comfort. Proper acoustic design requires both the use of high acoustic absorption and an appropriate masking sound.

Effects of acoustic environment on work in private office rooms and open-plan offices - longitudinal study during relocation

The aim was to determine how the perceived work environment, especially acoustic environment, and its effects differed in private office rooms and in open-plan offices. The subjects consisted of 31 workers who moved from private office rooms to open-plan offices and who answered the questionnaire before and after the relocation. Private office rooms were occupied only by one person while open-plan offices were occupied by more than 20 persons. Room acoustical descriptors showed a significant reduction in speech privacy after relocation. The noise level averaged over the whole work day did not change but the variability of noise level reduced significantly. Negative effects of acoustic environment increased significantly, including increased distraction, reduced privacy, increased concentration difficulties and increased use of coping strategies. Self-rated loss of work performance because of noise doubled. Cognitively demanding work and phone conversations were most distracted by noise. The benefits that are often associated with open-plan offices did not appear: cooperation became less pleasant and direct and information flow did not change. Nowadays, most office workers, independent of job type, are located in open-plan offices without the individual needs of privacy, concentration and interaction being analysed. This intervention study consisted of professional workers. Their work tasks mainly required individual efforts, and interaction between other workers was not of primary concern, although necessary. The results suggest that the open-plan office is not recommended for professional workers. Similar intervention studies should also be made for other job types.

Fine-tuned: Phonology and Semantics Affect First- to Second-language Zooming In

We investigate how L1 phonology and semantics affect processing of interlingual homographs by manipulating language context before, and auditory input during, a visual experiment in the L2. Three experiments contained German–English homograph primes (gift = German “poison”) in English sentences and was performed by German (L1) learners of English (L2). Both reaction times and event-related brain potentials were measured on targets reflecting the German meaning of the interlingual homograph. In Experiment 1, participants viewed a pre-experiment English film, then half of the participants (n = 16) heard noise and the other half (n = 16) heard German pseudowords during the experiment; in Experiment 2, participants (n = 16) viewed a pre-experiment German film then heard noise; and in Experiment 3, participants (n = 16) viewed the pre-experiment English film then heard real German words. Those who had viewed the English film then heard noise during Experiment 1 showed no L1 influence. Those who saw the English film but heard German pseudowords during Experiment 1, or viewed the German film before and heard noise during Experiment 2, showed L1 influence as indicated by N400 priming of L1-related targets in the first half of the experiment. This suggests that a pre-experiment film in the L1 or the presence of L1 phonology during the experiment slowed down adjustment to the L2 task. In Experiment 3 with real L1 words in the background, N400 priming of L1 meanings was observed throughout the entire experiment for lower-proficiency participants. We discuss our findings in terms of context types that affect L1-to-L2 adjustment.

The impact of background speech varying in intelligibility: effects on cognitive performance and perceived disturbance

Noise abatement in office environments often focuses on the reduction of background speech intelligibility and noise level, as attainable with frequency-specific insulation. However, only limited empirical evidence exists regarding the effects of reducing speech intelligibility on cognitive performance and subjectively perceived disturbance. Three experiments tested the impact of low background speech (35 dB(A)) of both good and poor intelligibility, in comparison to silence and highly intelligible speech not lowered in level (55 dB(A)). The disturbance impact of the latter speech condition on verbal short-term memory (n=20) and mental arithmetic (n=24) was significantly reduced during soft and poorly intelligible speech, but not during soft and highly intelligible speech. No effect of background speech on verbal-logical reasoning performance (n=28) was found. Subjective disturbance ratings, however, were consistent over all three experiments with, for example, soft and poorly intelligible speech rated as the least disturbing speech condition but still disturbing in comparison to silence. It is concluded, therefore, that a combination of objective performance tests and subjective ratings is desirable for the comprehensive evaluation of acoustic office environments and their alterations.