Simultaneous interpreting, brain aging, and cognition

Aging is associated with a high prevalence of neural and cognitive changes, which may impair life quality while placing a significant burden on the healthcare system and the economy. Nevertheless, diverse daily activities as well as deliberate practice in several domains have been proposed to benefit brain plasticity and cognition as well as to have the potential to counteract age-related decline through neuroprotective and/or compensatory mechanisms. In this review article, we will provide a summary of the gray matter alterations that have commonly been documented in simultaneous interpreters over the past twenty years. Furthermore, we will review the main literature that examined associations between simultaneous interpreting training and cognitive functions for assessing possible practice-related cognitive benefits in older age. We will also outline future directions for research in this area and highlight interventions aimed at mitigating the effects of aging on neurocognition

Cellular kinases incorporated into HIV-1 particles: passive or active passengers?

Phosphorylation is one of the major mechanisms by which the activities of protein factors can be regulated. Such regulation impacts multiple key-functions of mammalian cells, including signal transduction, nucleo-cytoplasmic shuttling, macromolecular complexes assembly, DNA binding and regulation of enzymatic activities to name a few. To ensure their capacities to replicate and propagate efficiently in their hosts, viruses may rely on the phosphorylation of viral proteins to assist diverse steps of their life cycle. It has been known for several decades that particles from diverse virus families contain some protein kinase activity. While large DNA viruses generally encode for viral kinases, RNA viruses and more precisely retroviruses have acquired the capacity to hijack the signaling machinery of the host cell and to embark cellular kinases when budding. Such property was demonstrated for HIV-1 more than a decade ago. This review summarizes the knowledge acquired in the field of HIV-1-associated kinases and discusses their possible function in the retroviral life cycle

Improvements in naturalistic speech-in-noise comprehension in middle-aged and older adults after 3 weeks of computer-based speechreading training

Problems in understanding speech in noisy environments are characteristic for age-related hearing loss. Since hearing aids do not mitigate these communication problems in every case, potential alternatives in a clinical rehabilitation plan need to be explored. This study investigates whether a computer-based speechreading training improves audiovisual speech perception in noise in a sample of middle-aged and older adults (N = 62, 47–83 years) with 32 participants completing a speechreading training and 30 participants of an active control group completing a foreign language training. Before and after training participants performed a speech-in-noise task mimicking real-life communication settings with participants being required to answer a speaker’s questions. Using generalized linear mixed-effects models we found a significant improvement in audiovisual speech perception in noise in the speechreading training group. This is of great relevance as these results highlight the potential of a low-cost and easy-to-implement intervention for a profound and widespread problem as speech-in-noise comprehension impairment

A multidimensional characterization of the neurocognitive architecture underlying age-related temporal speech processing.

Healthy aging is often associated with speech comprehension difficulties in everyday life situations despite a pure-tone hearing threshold in the normative range. Drawing on this background, we used a multidimensional approach to assess the functional and structural neural correlates underlying age-related temporal speech processing while controlling for pure-tone hearing acuity. Accordingly, we combined structural magnetic resonance imaging and electroencephalography, and collected behavioral data while younger and older adults completed a phonetic categorization and discrimination task with consonant-vowel syllables varying along a voice-onset time continuum. The behavioral results confirmed age-related temporal speech processing singularities which were reflected in a shift of the boundary of the psychometric categorization function, with older adults perceiving more syllable characterized by a short voice-onset time as /ta/ compared to younger adults. Furthermore, despite the absence of any between-group differences in phonetic discrimination abilities, older adults demonstrated longer N100/P200 latencies as well as increased P200 amplitudes while processing the consonant-vowel syllables varying in voice-onset time. Finally, older adults also exhibited a divergent anatomical gray matter infrastructure in bilateral auditory-related and frontal brain regions, as manifested in reduced cortical thickness and surface area. Notably, in the younger adults but not in the older adult cohort, cortical surface area in these two gross anatomical clusters correlated with the categorization of consonant-vowel syllables characterized by a short voice-onset time, suggesting the existence of a critical gray matter threshold that is crucial for consistent mapping of phonetic categories varying along the temporal dimension. Taken together, our results highlight the multifaceted dimensions of age-related temporal speech processing characteristics, and pave the way toward a better understanding of the relationships between hearing, speech and the brain in older age

The neuroanatomical hallmarks of chronic tinnitus in comorbidity with pure-tone hearing loss

Tinnitus is one of the main hearing impairments often associated with pure-tone hearing loss, and typically manifested in the perception of phantom sounds. Nevertheless, tinnitus has traditionally been studied in isolation without necessarily considering auditory ghosting and hearing loss as part of the same syndrome. Hence, in the present neuroanatomical study, we attempted to pave the way toward a better understanding of the tinnitus syndrome, and compared two groups of almost perfectly matched individuals with (TIHL) and without (NTHL) pure-tone tinnitus, but both characterized by pure-tone hearing loss. The two groups were homogenized in terms of sample size, age, gender, handedness, education, and hearing loss. Furthermore, since the assessment of pure-tone hearing thresholds alone is not sufficient to describe the full spectrum of hearing abilities, the two groups were also harmonized for supra-threshold hearing estimates which were collected using temporal compression, frequency selectivity und speech-in-noise tasks. Regions-of-interest (ROI) analyses based on key brain structures identified in previous neuroimaging studies showed that the TIHL group exhibited increased cortical volume (CV) and surface area (CSA) of the right supramarginal gyrus and posterior planum temporale (PT) as well as CSA of the left middle-anterior part of the superior temporal sulcus (STS). The TIHL group also demonstrated larger volumes of the left amygdala and of the left head and body of the hippocampus. Notably, vertex-wise multiple linear regression analyses additionally brought to light that CSA of a specific cluster, which was located in the left middle-anterior part of the STS and overlapped with the one found to be significant in the between-group analyses, was positively associated with tinnitus distress level. Furthermore, distress also positively correlated with CSA of gray matter vertices in the right dorsal prefrontal cortex and the right posterior STS, whereas tinnitus duration was positively associated with CSA and CV of the right angular gyrus (AG) and posterior part of the STS. These results provide new insights into the critical gray matter architecture of the tinnitus syndrome matrix responsible for the emergence, maintenance and distress of auditory phantom sensations

Older adults’ neural tracking of interrupted speech is a function of task difficulty

Age-related hearing loss is a highly prevalent condition, which manifests at both the auditory periphery and the brain. It leads to degraded auditory input, which needs to be repaired in order to achieve understanding of spoken language. It is still unclear how older adults with this condition draw on their neural resources to optimally process speech. By presenting interrupted speech to 26 healthy older adults with normal-for-age audiograms, this study investigated neural tracking of degraded auditory input. The electroencephalograms of the participants were recorded while they first listened to and then verbally repeated sentences interrupted by silence in varying interruption rates. Speech tracking was measured by inter-trial phase coherence in response to the stimuli. In interruption rates that corresponded to the theta frequency band, speech tracking was highly specific to the interruption rate and positively related to the understanding of interrupted speech. These results suggest that older adults’ brain activity optimizes through the tracking of stimulus characteristics, and that this tracking aids in processing an incomplete auditory stimulus. Further investigation of speech tracking as a candidate training mechanism to alleviate age-related hearing loss is thus encouraged

Promoting hearing and cognitive health in audiologic rehabilitation for the well-being of older adults

Objective: With our aging population, an increasing number of older adults with hearing loss have cognitive decline. Hearing care practitioners have an important role in supporting healthy aging and should be knowledgeable about cognitive decline and associated management strategies to maximize successful hearing intervention. Methods: A review of current research and expert opinion. Results: This article outlines the association between hearing loss and cognitive decline/dementia, hypothesized mechanisms underlying this, and considers current research into the effects of hearing intervention on cognitive decline. Cognition into old age, cognitive impairment, dementia, and how to recognize cognitive decline that is not part of normal aging are described. Screening of older asymptomatic adults for cognitive decline and practical suggestions for the delivery of person-centered hearing care are discussed. Holistic management goals, personhood, and person-centered care in hearing care management are considered for older adults with normal cognitive aging through to dementia. A case study illustrates important skills and potential management methods. Prevention strategies for managing hearing and cognitive health and function through to older age, and strategies to maximize successful hearing aid use are provided. Conclusion: This article provides evidence-based recommendations for hearing care professionals supporting older clients to maximize well-being through the cognitive trajectory

HIV-1-associated PKA acts as a cofactor for genome reverse transcription

BACKGROUND: Host cell proteins, including cellular kinases, are embarked into intact HIV-1 particles. We have previously shown that the Cα catalytic subunit of cAMP-dependent protein kinase is packaged within HIV-1 virions as an enzymatically active form able to phosphorylate a synthetic substrate in vitro (Cartier et al. J. Biol. Chem. 278:35211 (2003)). The present study was conceived to investigate the contribution of HIV-1-associated PKA to the retroviral life cycle. RESULTS: NL4.3 viruses were produced from cells cultured in the presence of PKA inhibitors H89 (H89-NL4.3) or Myr-PKI (PKI-NL4.3) and analyzed for viral replication. Despite being mature and normally assembled, and containing expected levels of genomic RNA and RT enzymatic activity, such viruses showed poor infectivity. Indeed, infection generated reduced amounts of strong-strop minus strand DNA, while incoming RNA levels in target cells were unaffected. Decreased cDNA synthesis was also evidenced in intact H89-NL4.3 and PKI-NL4.3 cell free particles using endogenous reverse transcription (ERT) experiments. Moreover, similar defects were reproduced when wild type NL4.3 particles preincubated with PKA inhibitors were subjected to ERT reactions. CONCLUSIONS: Altogether, our results indicate that HIV-1-associated PKA is required for early reverse transcription of the retroviral genome both in cell free intact viruses and in target cells. Accordingly, virus-associated PKA behaves as a cofactor of an intraviral process required for optimal reverse transcription and for early post-entry events