Doctoral Studies as part of an Innovative Training Network (ITN): Early Stage Researcher (ESR) experiences [version 2; peer review: 2 approved]

Background: The Marie-Skłodowska-Curie Actions’ (MSCA) Innovative Training Network (ITN) is a doctoral training programme jointly implemented by academic institutions and industries from countries across Europe and beyond. To our knowledge no study has examined the experience of students participating in MSCA-ITNs. This study aims to evaluate and report MSCA-ITN Early Stage Researcher (ESR) experiences. Methods: The Innovative Training Network - Evaluation Questionnaire (ITN-EQ) was developed to assess supervision, training, collaborations and experiences of ESRs and forwarded to two tinnitus-related ITNs and seven ITNs of other disciplines. Results: Key advantages identified included better career prospects, multidisciplinary research opportunities/collaborations, international exposure, personal/professional development, plus generous salaries and research budgets. However, lack of a common EU framework resulted in the experience being largely dependent on the host institution, country and supervisor. Moreover, managing the dual requirements of ITNs and host institutions while completing a three-year PhD seemed challenging for most ESRs. ESR involvement in workshop and training school planning was desirable. More than 80% of ESRs rated the overall ITN experience favourably and 98.3% would recommend the same to prospective PhD students. Conclusions: This report could provide valuable insights in planning and management of future ITNs and could assist prospective students in their decision of joining an ITN for their PhD

Doctoral Studies as part of an Innovative Training Network (ITN):Early Stage Researcher (ESR) experiences [version 2; peer review: 2 approved]

Background: The Marie-Skłodowska-Curie Actions’ (MSCA) Innovative Training Network (ITN) is a doctoral training programme jointly implemented by academic institutions and industries from countries across Europe and beyond. To our knowledge no study has examined the experience of students participating in MSCA-ITNs. This study aims to evaluate and report MSCA-ITN Early Stage Researcher (ESR) experiences. Methods: The Innovative Training Network - Evaluation Questionnaire (ITN-EQ) was developed to assess supervision, training, collaborations and experiences of ESRs and forwarded to two tinnitus-related ITNs and seven ITNs of other disciplines. Results: Key advantages identified included better career prospects, multidisciplinary research opportunities/collaborations, international exposure, personal/professional development, plus generous salaries and research budgets. However, lack of a common EU framework resulted in the experience being largely dependent on the host institution, country and supervisor. Moreover, managing the dual requirements of ITNs and host institutions while completing a three-year PhD seemed challenging for most ESRs. ESR involvement in workshop and training school planning was desirable. More than 80% of ESRs rated the overall ITN experience favourably and 98.3% would recommend the same to prospective PhD students. Conclusions: This report could provide valuable insights in planning and management of future ITNs and could assist prospective students in their decision of joining an ITN for their PhD

Etude des effets du traumatisme sonore sur une colonne corticale du cortex auditif primaire

Le présent projet a pour but d'étudier les effets spécifiques des couches lors des activités spontanées et provoquées par le son après un traumatisme sonore aigu et chronique. Plus important encore, nous avons étudié les changements laminaires spatio-temporels dans les deux activités après un traumatisme sonore. Nos résultats montrent que le taux de tir et les potentiels de champ locaux pendant les activités spontanées et provoquées par le son ont été modifiés de façon spectaculaire dans toutes les couches corticales dans la région de fréquence inférieure et supérieure à la fréquence du traumatisme. L'exposition au bruit a considérablement modifié la structure spatio-temporelle de l'activité spontanée et provoquée par le son. Dans l'activité spontanée, nous montrons que la couche supragranulaire devient un récepteur d'entrée majeur dans les deux régions de fréquence après un traumatisme aigu et chronique. Après un traumatisme aigu, l'activité provoquée par le son a été renforcée dans toutes les couches de la région Be_TF et seulement dans les couches infragranulaires de la région Ab_TF. Inversement, l'activité synaptique dans les couches supragranulaires et granulaires était significativement accrue dans les deux régions de fréquence après un traumatisme chronique. Dans l'ensemble, le traumatisme sonore a eu des effets spécifiques aux couches et aux fréquences dans l'activité spontanée et provoquée par le son. De plus, nous suggérons que la propagation accrue de l'activité corticale à travers une colonne corticale induit un couplage fonctionnel aberrant du réseau cérébral étendu qui pourrait conduire à la génération de perceptions conscientes telles que les acouphènes.The present project is aimed at studying the layer-specific effects during spontaneous and sound-evoked activity after acute and chronic noise trauma. Importantly, we investigated the spatiotemporal laminar changes in both the activities after noise trauma. Our results show that firing rate and local field potentials during spontaneous and sound-evoked activities were altered dramatically at all cortical layers in the frequency region below and above the trauma frequency. Noise exposure substantially altered the spatiotemporal structure of the spontaneous and sound-evoked activity. In the spontaneous activity, we show that the supragranular layer becomes a major input recipient in both frequency regions after acute and chronic trauma. After acute trauma, the sound-evoked activity was enhanced at all layers in the Be_TF region and only in the infragranular layers in the Ab_TF region. Conversely, synaptic activity in the supragranular and granular layers was significantly increased in both the frequency regions after chronic trauma. Overall, noise trauma had layer and frequency-specific effects in both spontaneous and sound-evoked activity. Further, we suggest that enhanced propagation of cortical activity across a cortical column induces aberrant functional coupling of the widespread brain network which could lead tthe o generation of conscious percept such as tinnitus

Offset responses in primary auditory cortex are enhanced after notched noise stimulation

Notched noise (white noise with embedded spectral gap) causes significant excitatory offset responses in the auditory cortex of awake and anesthetized guinea pigs. The largest offset responses were located in the infragranular/granular layers, and current source density analysis revealed that offset responses were associated with an early current sink localized in the upper infragranular layers. We discuss the possibility that the offset responses might be associated with an auditory phantom percept (Zwicker tone)

Noise-Induced Hearing Loss Alters Potassium-Chloride CoTransporter KCC2 and GABA Inhibition in the auditory centers

Abstract Homeostatic plasticity, the ability of neurons to maintain their averaged activity constant around a set point value, is thought to account for the central hyperactivity after hearing loss. Here, we investigated the putative role of GABAergic neurotransmission in this mechanism after a noise-induced hearing loss larger than 50 dB in high frequencies in guinea pigs. The effect of GABAergic inhibition is linked to the normal functioning of K+‒Cl- co-transporter isoform 2 (KCC2) which maintains a low intracellular concentration of chloride. The expression of membrane KCC2 were investigated before after noise trauma in the ventral and dorsal cochlear nucleus (VCN and DCN, respectively) and in the inferior colliculus (IC). Moreover, the effect of gabazine (GBZ), a GABA antagonist, was also studied on the neural activity in IC. We show that KCC2 is downregulated in VCN, DCN and IC 3 days after noise trauma, and in DCN and IC 30 days after the trauma. As expected, GBZ application in the IC of control animals resulted in an increase of spontaneous and stimulus-evoked activity. In the noise exposed animals, on the other hand, GBZ application decreased the stimulus-evoked activity in IC neurons. The functional implications of these central changes are discussed

Identification and removal of reflection artifacts in minimally invasive photoacoustic imaging for accurate visualization of brachytherapy seeds

Reflection artifacts caused by the high signal from the optical fiber/ needle tip reflecting off the seed is an important problem in minimally invasive photoacoustic imaging of brachytherapy seeds. The presence of these artifacts confounds the interpretation of images and reduces contrast. We apply a new method called PAFUSion (Photoacoustic-guided focused ultrasound) to identify and reduce reflection artifacts generated in interstitial illumination imaging of brachytherapy seeds. We present the system comprising of a US imager and linear array, with illumination provided via a cutting needle. Non-radioactive brachytherapy seeds are implanted in a tissue mimicking phantom and ex vivo porcine tissue. The PAFUSion-corrected imaging results successfully demonstrate that our approach can identify and strongly reduce reflection artifacts in the context of photoacoustic needle. The phantom result also shows that multi-spectral photoacoustics can separate signals between the seeds and other optical absorbers

Photoacoustic-guided focused ultrasound for accurate visualization of brachytherapy seeds with the photoacoustic needle

An important problem in minimally invasive photoacoustic (PA) imaging of brachytherapy seeds is reflection artifacts caused by the high signal from the optical fiber/needle tip reflecting off the seed. The presence of these artifacts confounds interpretation of images. In this letter, we demonstrate a recently developed concept called photoacoustic-guided focused ultrasound (PAFUSion) for the first time in the context of interstitial illumination PA imaging to identify and remove reflection artifacts. In this method, ultrasound (US) from the transducer is focused on the region of the optical fiber/needle tip identified in a first step using PA imaging. The image developed from the US diverging from the focus zone at the tip region visualizes only the reflections from seeds and other acoustic inhomogeneities, allowing identification of the reflection artifacts of the first step. These artifacts can then be removed from the PA image. Using PAFUSion, we demonstrate reduction of reflection artifacts and thereby improved interstitial PA visualization of brachytherapy seeds in phantom and ex vivo measurements on porcine tissue

Doctoral Studies as part of an Innovative Training Network (ITN): Early Stage Researcher (ESR) experiences [version 2; peer review: 2 approved with reservations]

Background: The Marie-Skłodowska-Curie Actions’ (MSCA) Innovative Training Network (ITN) is a doctoral training programme jointly implemented by academic institutions and industries from countries across Europe and beyond. To our knowledge no study has examined the experience of students participating in MSCA-ITNs. This study aims to evaluate and report MSCA-ITN Early Stage Researcher (ESR) experiences. Methods: The Innovative Training Network - Evaluation Questionnaire (ITN-EQ) was developed to assess supervision, training, collaborations and experiences of ESRs and forwarded to two tinnitus-related ITNs and seven ITNs of other disciplines. Results: Key advantages identified included better career prospects, multidisciplinary research opportunities/collaborations, international exposure, personal/professional development, plus generous salaries and research budgets. However, lack of a common EU framework resulted in the experience being largely dependent on the host institution, country and supervisor. Moreover, managing the dual requirements of ITNs and host institutions while completing a three-year PhD seemed challenging for most ESRs. ESR involvement in workshop and training school planning was desirable. More than 80% of ESRs rated the overall ITN experience favourably and 98.3% would recommend the same to prospective PhD students. Conclusions: This report could provide valuable insights in planning and management of future ITNs and could assist prospective students in their decision of joining an ITN for their PhD