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

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

Prostaglandin E2 metabolism in rat brain: Role of the blood-brain interfaces

<p>Abstract</p> <p>Background</p> <p>Prostaglandin E₂(PGE₂) is involved in the regulation of synaptic activity and plasticity, and in brain maturation. It is also an important mediator of the central response to inflammatory challenges. The aim of this study was to evaluate the ability of the tissues forming the blood-brain interfaces to act as signal termination sites for PGE₂by metabolic inactivation.</p> <p>Methods</p> <p>The specific activity of 15-hydroxyprostaglandin dehydrogenase was measured in homogenates of microvessels, choroid plexuses and cerebral cortex isolated from postnatal and adult rat brain, and compared to the activity measured in peripheral organs which are established signal termination sites for prostaglandins. PGE₂metabolites produced <it>ex vivo </it>by choroid plexuses were identified and quantified by HPLC coupled to radiochemical detection.</p> <p>Results</p> <p>The data confirmed the absence of metabolic activity in brain parenchyma, and showed that no detectable activity was associated with brain microvessels forming the blood-brain barrier. By contrast, 15-hydroxyprostaglandin dehydrogenase activity was measured in both fourth and lateral ventricle choroid plexuses from 2-day-old rats, albeit at a lower level than in lung or kidney. The activity was barely detectable in adult choroidal tissue. Metabolic profiles indicated that isolated choroid plexus has the ability to metabolize PGE₂, mainly into 13,14-dihydro-15-keto-PGE₂. In short-term incubations, this metabolite distributed in the tissue rather than in the external medium, suggesting its release in the choroidal stroma.</p> <p>Conclusion</p> <p>The rat choroidal tissue has a significant ability to metabolize PGE₂during early postnatal life. This metabolic activity may participate in signal termination of centrally released PGE₂in the brain, or function as an enzymatic barrier acting to maintain PGE₂homeostasis in CSF during the critical early postnatal period of brain development.</p

Partying Critics: A Dual Take on Duality in Graham Greene’s “The End of the Party”

In this article, two French scholars look back on their practices as critics via a double, reflexive analysis of Graham Greene’s short story, “The End of the Party.” While they belong to the same generation, they were influenced by different theoretical backgrounds: French classical narratology and French theory on the one hand, post-classical narratology and cognitive poetics on the other. This approach was a means for them to assess the nature and relevance of their critical tools, figure out how these tools impact the reading of a selected text and what they reveal about their respective academic practices of literature. From a practical point of view, they worked on the same short story, each writing an independent analysis, and then produced a joint commentary in order to see what the process revealed about their respective approaches to literary theory. The purpose of this strategy was to better understand their critical methods but also the stakes inherent in literary interpretation at the beginning of the twenty first century. Eventually, they hope that this dual analysis will contribute to renew their respective methods.Dans cet article, deux universitaires français reviennent sur leurs pratiques en tant que chercheurs en littérature par le biais d’une double analyse de la nouvelle de Graham Greene « The End of the Party ». Bien qu’appartenant à la même génération, ils ont été influencés par des champs théoriques différents : la narratologie classique et ce qu’on appelle la French theory pour l’une, la narratologie postclassique et la poétique cognitive pour l’autre. Cette analyse fut l’occasion pour eux de faire un bilan de leurs outils critiques, d’interroger la nature et la validité de ces outils et ainsi de comprendre dans quelle mesure ceux-ci influencent leur lecture d’un même texte, et ce qu’ils révèlent de leurs méthodes herméneutiques en général. D’un point de vue pratique, ils ont travaillé sur la même nouvelle, en ont proposé chacun une étude, et produit en dernier lieu un commentaire commun, en tentant de mettre en évidence ce que cette façon de travailler révèle de leurs approches respectives de la théorie littéraire. Cette stratégie visait à mieux comprendre leurs méthodes critiques mais aussi les enjeux inhérents à l’interprétation littéraire au début du vingt-et-unième siècle. In fine, ils espèrent que cette double lecture contribuera à renouveler la méthode de chacun

The role of eye movements in a contour detection task

Vision combines local feature integration with active viewing processes, such as eye movements, to perceive complex visual scenes. However, it is still unclear how these processes interact and support each other. Here, we investigated how the dynamics of saccadic eye movements interact with contour integration, focusing on situations in which contours are difficult to find or even absent. We recorded observers&apos; eye movements while they searched for a contour embedded in a background of randomly oriented elements. Task difficulty was manipulated by varying the contour&apos;s path angle. An association field model of contour integration was employed to predict potential saccade targets by identifying stimulus locations with high contour salience. We found that the number and duration of fixations increased with the increasing path angle of the contour. In addition, fixation duration increased over the course of a trial, and the time course of saccade amplitude depended on the percept of observers. Model fitting revealed that saccades fully compensate for the reduced saliency of peripheral contour targets. Importantly, our model predicted fixation locations to a considerable degree, indicating that observers fixated collinear elements. These results show that contour integration actively guides eye movements and determines their spatial and temporal parameters

Projet collectif de recherche : cartographie de l'espace parisien

Rapport final d'activité du PCR 2005-200

Tox2 is required for the maintenance of GC TFH cells and the generation of memory TFH cells

効率よい抗体反応の形成に必要なTリンパ球因子の発見. 京都大学プレスリリース. 2021-10-15.Molecules for building stronger antibodies. 京都大学プレスリリース. 2021-10-15.Memory T follicular helper (TFH) cells play an essential role to induce secondary antibody response by providing help to memory and naïve B cells. Here, we show that the transcription factor Tox2 is vital for the maintenance of TFH cells in germinal centers (GCs) and the generation of memory TFH cells. High Tox2 expression was almost exclusive to GC TFH cells among human tonsillar and blood CD4+ T cell subsets. Tox2 overexpression maintained the expression of TFH-associated genes in T cell receptor–stimulated human GC TFH cells and inhibited their spontaneous conversion into TH1-like cells. Tox2-deficient mice displayed impaired secondary TFH cell expansion upon reimmunization with an antigen and upon secondary infection with a heterologous influenza virus. Collectively, our study shows that Tox2 is highly integrated into establishment of durable GC TFH cell responses and development of memory TFH cells in mice and humans