Brain aging and speech perception : effects of background noise and talker variability

Speech perception can be challenging, especially for older adults. Despite the importance of speech perception in social interactions, the mechanisms underlying these difficulties remain unclear and treatment options are scarce. While several studies have suggested that decline within cortical auditory regions may be a hallmark of these difficulties, a growing number of studies have reported decline in regions beyond the auditory processing network, including regions involved in speech processing and executive control, suggesting a potentially diffuse underlying neural disruption, though no consensus exists regarding underlying dysfunctions. To address this issue, we conducted two experiments in which we investigated age differences in speech perception when background noise and talker variability are manipulated, two factors known to be detrimental to speech perception. In Experiment 1, we examined the relationship between speech perception, hearing and auditory attention in 88 healthy participants aged 19 to 87 years. In Experiment 2, we examined cortical thickness and BOLD signal using magnetic resonance imaging (MRI) and related these measures to speech perception performance using a simple mediation approach in 32 participants from Experiment 1. Our results show that, even after accounting for hearing thresholds and two measures of auditory attention, speech perception significantly declined with age. Age-related decline in speech perception in noise was associated with thinner cortex in auditory and speech processing regions (including the superior temporal cortex, ventral premotor cortex and inferior frontal gyrus) as well as in regions involved in executive control (including the dorsal anterior insula, the anterior cingulate cortex and medial frontal cortex). Further, our results show that speech perception performance was associated with reduced brain response in the right superior temporal cortex in older compared to younger adults, and to an increase in response to noise in older adults in the left anterior temporal cortex. Talker variability was not associated with different activation patterns in older compared to younger adults. Together, these results support the notion of a diffuse rather than a focal dysfunction underlying speech perception in noise difficulties in older adults

Age differences in the motor control of speech : an fMRI study of healthy aging

Healthy aging is associated with a decline in cognitive, executive, and motor processes that are concomitant with changes in brain activation patterns, particularly at high complexity levels. While speech production relies on all these processes, and is known to decline with age, the mechanisms that underlie these changes remain poorly understood, despite the importance of communication on everyday life. In this cross‐sectional group study, we investigated age differences in the neuromotor control of speech production by combining behavioral and functional magnetic resonance imaging (fMRI) data. Twenty‐seven healthy adults underwent fMRI while performing a speech production task consisting in the articulation of nonwords of different sequential and motor complexity. Results demonstrate strong age differences in movement time (MT), with longer and more variable MT in older adults. The fMRI results revealed extensive age differences in the relationship between BOLD signal and MT, within and outside the sensorimotor system. Moreover, age differences were also found in relation to sequential complexity within the motor and attentional systems, reflecting both compensatory and de‐differentiation mechanisms. At very high complexity level (high motor complexity and high sequence complexity), age differences were found in both MT data and BOLD response, which increased in several sensorimotor and executive control areas. Together, these results suggest that aging of motor and executive control mechanisms may contribute to age differences in speech production. These findings highlight the importance of studying functionally relevant behavior such as speech to understand the mechanisms of human brain aging

The structural correlates of statistical information processing during speech perception

The processing of continuous and complex auditory signals such as speech relies on the ability to use statistical cues (e.g. transitional probabilities). In this study, participants heard short auditory sequences composed either of Italian syllables or bird songs and completed a regularity-rating task. Behaviorally, participants were better at differentiating between levels of regularity in the syllable sequences than in the bird song sequences. Inter-individual differences in sensitivity to regularity for speech stimuli were correlated with variations in surface-based cortical thickness (CT). These correlations were found in several cortical areas including regions previously associated with statistical structure processing (e.g. bilateral superior temporal sulcus, left precentral sulcus and inferior frontal gyrus), as well other regions (e.g. left insula, bilateral superior frontal gyrus/sulcus and supramarginal gyrus). In all regions, this correlation was positive suggesting that thicker cortex is related to higher sensitivity to variations in the statistical structure of auditory sequences. Overall, these results suggest that inter-individual differences in CT within a distributed network of cortical regions involved in statistical structure processing, attention and memory is predictive of the ability to detect structural structure in auditory speech sequences

Age differences in voice evaluation : from auditory-perceptual evaluation to social interactions

Purpose: The factors that influence the evaluation of voice in adulthood, as well as the consequences of such evaluation on social interactions, are not well understood. Here, we examined the effect of listeners' age and the effect of talker age, sex, and smoking status on the auditory-perceptual evaluation of voice, voice-related psychosocial attributions, and perceived speech tempo. We also examined the voice dimensions affecting the propensity to engage in social interactions. Method: Twenty-five younger (age 19-37 years) and 25 older (age 51-74 years) healthy adults participated in this cross-sectional study. Their task was to evaluate the voice of 80 talkers. Results: Statistical analyses revealed limited effects of the age of the listener on voice evaluation. Specifically, older listeners provided relatively more favorable voice ratings than younger listeners, mainly in terms of roughness. In contrast, the age of the talker had a broader impact on voice evaluation, affecting auditory-perceptual evaluations, psychosocial attributions, and perceived speech tempo. Some of these talker differences were dependent upon the sex of the talker and his or her smoking status. Finally, the results also show that voice-related psychosocial attribution was more strongly associated with the propensity of the listener to engage in social interactions with a person than auditory-perceptual dimensions and perceived speech tempo, especially for the younger adults. Conclusions: These results suggest that age has a broad influence on voice evaluation, with a stronger impact for talker age compared with listener age. While voice-related psychosocial attributions may be an important determinant of social interactions, perceived voice quality and speech tempo appear to be less influential

How to Develop an Impactful Action Research Program: Insights and Lessons from a Case Study

Action research holds great potential for helping bridge the gap between research and practice. By working closely together, researchers and practitioners can develop tangible customized solutions based on research findings. It becomes possible to go beyond generic best practices that might need adaptation for successful implementation and use, or that may not apply at all in some contexts. In this article, the mechanisms through which action research can create the desired change and impact in both industry and academia are illustrated by describing the relevance and contribution of the main steps of a longitudinal action research program in a Canadian manufacturing company. The authors share four guiding principles and six success factors that were revealed intuitively in the course of this multi-year research program. Their hope is to contribute to a better understanding of how it is possible to develop an adaptive action research methodology to increase the potential for research relevance and organizational change

How to develop innovation KPIs in an execution-oriented company

Numerous established companies look for ways to rejuvenate their innovation capabilities, as it is essential for their long-term survival. One way is through the development of key performance indicators (KPIs) to measure innovation success. However, the wrong performance measurement approach can hinder innovation efforts. This case study explores the steps and challenges associated with the development of innovation KPIs in an established execution-oriented manufacturing company. Three prerequisites are proposed for such a project in a similar context: 1) a minimal maturity level of innovation processes, 2) strategic alignment, and 3) commitment to innovation. It is also proposed that, in such an execution-oriented company, it might be more effective to start with KPIs that would encourage behaviours more favourable to innovation. Then, with stronger innovation capabilities, it will be easier to develop appropriate KPIs to measure the success of innovation endeavours

University-SME collaboration and open innovation: Intellectual-property management tools and the roles of intermediaries

In 2009, the Conseil de la science et de la technologie du Québec (CST) made 13 recommendations to the Government of Quebec in order to shift innovative actors towards open-innovation practices adapted to the province's context: diversified economic sectors, a majority of small and medium-sized enterprises (SMEs), public universities, etc. Among these recommendations are: i) to set up flexible mechanisms to promote research collaboration between public-private sectors such as universities and SMEs, and ii) to optimize intermediation bodies’ contribution to establish open-innovation practices. Furthermore, the lack of adequate understanding and tools for the management of intellectual property (IP) was identified as a major inhibitor of open-innovation practices, to which actors should pay specific attention. In this article, we present results and recommendations from a field study focused on two groups of actors: i) companies involved in collaborative innovation and ii) intermediary agents enabling innovation and technology transfer. Our first goal was to shed some light on factors that facilitate open innovation through improved university-enterprise collaborations and, more importantly, that attempt to overcome the irritants related to IP management. Our second goal was to analyze the roles of diverse intermediaries in the fostering of successful collaborations between universities and SMEs. Our study yielded three findings: i) SMEs do not care about understanding and improving their capabilities about IP and are not equipped with adequate tools and best practices for managing IP and for managing the overall collaborative mechanisms in general; ii) this gap in preparation for open innovation is persistent, since even the intermediaries, whose role is to guide SMEs in university-enterprise collaborations, suffer themselves from the lack of appropriate IP transfer and sharing tools, and do not perceive the need to offer better support in this regard; and iii) overall, current IP-transfer and collaboration-management tools are not sophisticated enough to provide appropriate support for the implementation of open innovation, by which we mean more open and collaborative innovation in the context of university-enterprise collaborations

The neural correlates of referential communication : taking advantage of sparse-sampling fMRI to study verbal communication with a real interaction partner

This paper introduces an innovative functional magnetic resonance imaging (fMRI) protocol to study real verbal interactions while limiting the impact of speech-related movement artefacts. This protocol is based on a sparse sampling acquisition technique and allowed participants to complete a referential communication task with a real interaction partner. During verbal interactions, speakers adjust their verbal productions depending on their interlocutors' knowledge of the referents being mentioned. These adjustments have been linked to theory of mind (ToM), the ability to infer other's mental states. We thus sought to determine if the brain regions supporting ToM would also be activated during a referential communication task in which participants have to present movie characters that vary in their likelihood of being known by their interlocutor. This pilot study establishes that the sparse sampling strategy is a viable option to study the neural correlates of referential communication while minimizing movement artefacts. In addition, the brain regions supporting ToM were recruited during the task, though specifically for the conditions where participants could adjust their verbal productions to the interlocutor's likely knowledge of the referent. This study therefore demonstrates the feasibility and relevance of a sparse-sampling approach to study verbal interactions with fMRI, including referential communication

Introduction of innovative equipment in mining: Impact on occupational health and safety

Occupational health and safety in mining has clearly improved in developed countries over the past twenty years, but accidents and illness still occur with unacceptable frequency. The arrival of new mining equipment, bigger, more powerful and complex and requiring a higher skill level appears also to increase certain specific risks of accident and work-related illness. The objective of this paper is to examine the impact of new equipment on occupational health and safety in underground mining. The injury rate associated with eight equipment introduction projects was examined. The results show clearly that the introduction of new equipment with technological innovations does not automatically reduce the injury rate. The new equipment may even generate a higher injury rate than the equipment it replaced. Ergonomic deficiencies were noted in some of the new equipment. We suggest that future research focus on identifying the mechanisms and conditions that determine injury rate following the acquisition of innovative as means of improving occupational health and safety in mining. Successful implementation of new mining equipment appears to depend on the specific conditions of use