Using Optogenetic Dyadic Animal Models to Elucidate the Neural Basis for Human Parent-Infant Social Knowledge Transmission.

Healthy early development depends on a warm reciprocal relationship between parent and offspring, where parent and infant interact in close temporal co-ordination as if engaged in a “dyadic dance” of glances, gestures, smiles and words (Stern, 1985; Gianino and Tronick, 1988). Most, if not all, early learning takes place during these well-choreographed social exchanges, which support cultural knowledge transmission from parent to offspring using verbal and non-verbal forms of communication and behavioural modelling. Such vicarious knowledge transmission through social interaction (rather than direct experience) is known as social learning (Bandura, 1971; Csibra and Gergely, 2009). Tomasello (2014) argues that human mastery of these “second-personal social relations” (Darwall, 2006)—in which social partners share and create joint knowledge, intentionality and goals—has accelerated the rise of the human species through “cultural intelligence” (Herrmann et al., 2007).Ministry of Education (MOE)Published versionThis research is supported by the Ministry of Education, Singapore, under its Academic Research Fund Tier 1 [RG99/20 to VL and GA; RG152/18 (NS) to VL]

Overview of the first Wendelstein 7-X long pulse campaign with fully water-cooled plasma facing components

After a long device enhancement phase, scientific operation resumed in 2022. The main new device components are the water cooling of all plasma facing components and the new water-cooled high heat flux divertor units. Water cooling allowed for the first long-pulse operation campaign. A maximum discharge length of 8 min was achieved with a total heating energy of 1.3 GJ. Safe divertor operation was demonstrated in attached and detached mode. Stable detachment is readily achieved in some magnetic configurations but requires impurity seeding in configurations with small magnetic pitch angle within the edge islands. Progress was made in the characterization of transport mechanisms across edge magnetic islands: Measurement of the potential distribution and flow pattern reveals that the islands are associated with a strong poloidal drift, which leads to rapid convection of energy and particles from the last closed flux surface into the scrape-off layer. Using the upgraded plasma heating systems, advanced heating scenarios were developed, which provide improved energy confinement comparable to the scenario, in which the record triple product for stellarators was achieved in the previous operation campaign. However, a magnetic configuration-dependent critical heating power limit of the electron cyclotron resonance heating was observed. Exceeding the respective power limit leads to a degradation of the confinement

Interpretative and predictive modelling of Joint European Torus collisionality scans

Transport modelling of Joint European Torus (JET) dimensionless collisionality scaling experiments in various operational scenarios is presented. Interpretative simulations at a fixed radial position are combined with predictive JETTO simulations of temperatures and densities, using the TGLF transport model. The model includes electromagnetic effects and collisions as well as □(→┬E ) X □(→┬B ) shear in Miller geometry. Focus is on particle transport and the role of the neutral beam injection (NBI) particle source for the density peaking. The experimental 3-point collisionality scans include L-mode, and H-mode (D and H and higher beta D plasma) plasmas in a total of 12 discharges. Experimental results presented in (Tala et al 2017 44th EPS Conf.) indicate that for the H-mode scans, the NBI particle source plays an important role for the density peaking, whereas for the L-mode scan, the influence of the particle source is small. In general, both the interpretative and predictive transport simulations support the experimental conclusions on the role of the NBI particle source for the 12 JET discharges

Overview of physics studies on ASDEX Upgrade

The ASDEX Upgrade (AUG) programme, jointly run with the EUROfusion MST1 task force, continues to significantly enhance the physics base of ITER and DEMO. Here, the full tungsten wall is a key asset for extrapolating to future devices. The high overall heating power, flexible heating mix and comprehensive diagnostic set allows studies ranging from mimicking the scrape-off-layer and divertor conditions of ITER and DEMO at high density to fully non-inductive operation (q 95 = 5.5, ) at low density. Higher installed electron cyclotron resonance heating power 6 MW, new diagnostics and improved analysis techniques have further enhanced the capabilities of AUG. Stable high-density H-modes with MW m-1 with fully detached strike-points have been demonstrated. The ballooning instability close to the separatrix has been identified as a potential cause leading to the H-mode density limit and is also found to play an important role for the access to small edge-localized modes (ELMs). Density limit disruptions have been successfully avoided using a path-oriented approach to disruption handling and progress has been made in understanding the dissipation and avoidance of runaway electron beams. ELM suppression with resonant magnetic perturbations is now routinely achieved reaching transiently . This gives new insight into the field penetration physics, in particular with respect to plasma flows. Modelling agrees well with plasma response measurements and a helically localised ballooning structure observed prior to the ELM is evidence for the changed edge stability due to the magnetic perturbations. The impact of 3D perturbations on heat load patterns and fast-ion losses have been further elaborated. Progress has also been made in understanding the ELM cycle itself. Here, new fast measurements of and E r allow for inter ELM transport analysis confirming that E r is dominated by the diamagnetic term even for fast timescales. New analysis techniques allow detailed comparison of the ELM crash and are in good agreement with nonlinear MHD modelling. The observation of accelerated ions during the ELM crash can be seen as evidence for the reconnection during the ELM. As type-I ELMs (even mitigated) are likely not a viable operational regime in DEMO studies of 'natural' no ELM regimes have been extended. Stable I-modes up to have been characterised using -feedback. Core physics has been advanced by more detailed characterisation of the turbulence with new measurements such as the eddy tilt angle - measured for the first time - or the cross-phase angle of and fluctuations. These new data put strong constraints on gyro-kinetic turbulence modelling. In addition, carefully executed studies in different main species (H, D and He) and with different heating mixes highlight the importance of the collisional energy exchange for interpreting energy confinement. A new regime with a hollow profile now gives access to regimes mimicking aspects of burning plasma conditions and lead to nonlinear interactions of energetic particle modes despite the sub-Alfvénic beam energy. This will help to validate the fast-ion codes for predicting ITER and DEMO

Topological zones define basolateral amygdala synaptic input and functional organization of the claustrum

The claustrum (CLA) is a highly connected brain structure whose function is largely unknown. Given the prominent role of the basolateral amygdala (BLA) in emotional processing and valence coding, understanding the functional relationship between the CLA and the BLA may provide important insights into claustral function. I used viral-based tracing techniques, optogenetics and brain slice electrophysiology to dissect the circuit relationships between the BLA and the CLA. I uncovered a unique ring-like innervation of the CLA shell – but not the CLA core – by BLA axons. Although BLA inputs to both CLA regions were similar – mostly excitatory, weak and variable, differences in intrinsic excitability and action potential dynamics suggests potential differences in BLA input processing. M1-projecting and RSC-projecting claustral neurons exhibited differences in both their intrinsic electrical properties and their BLA input. In addition, retrograde tracing of M1-, RSC- and BLA-projecting claustral neurons revealed localization of these neurons into distinct claustral subregions, as well as unique projection networks with clear functional trends. My findings establish that the claustrum can be topologically separated into at least 3 distinct functional regions, which differ not only in their input sources, but also their projection networks, intrinsic electrical properties and, in some cases, BLA innervation. These findings represent a fundamental step toward understanding how the BLA regulates CLA activity and illuminates fundamental organizational principles of claustral network connectivity.Doctor of Philosoph

Topologically organized networks in the claustrum reflect functional modularization

Using genetic strategies and viral-based directional tracers, we investigated the topological location and output networks of claustrum (CLA) neuron populations projecting to either the retrosplenial cortex, primary motor cortex, or basolateral amygdala. We found that all three CLA neuron populations clearly reside in distinct topological locations within the CLA complex and project broadly to multiple downstream targets. Each neuron population projects to different targets, suggesting that each CLA subzone coordinates a unique set of brain-wide functions. Our findings establish that the claustrum complex encompasses at least three minimally overlapping networks that are compartmentalized into different topological subzones. Such modularity is likely to be important for CLA function.Ministry of Education (MOE)Published versionThis work was supported by grant MOE2017-T3-1-002 from the Singapore Ministry of Education

Synchrony in parent‐offspring social interactions across development: a cross‐species review of rodents and humans

In humans, parent-child neural synchrony has been shown to support early communication, social attunement and learning. Further, some animal species (including rodents and bats) are now known to share neural synchrony during certain forms of social behaviour. However, very little is known about the developmental origins and sequelae of neural synchrony, and whether this neural mechanism might play a causal role in the control of social and communicative behaviour across species. Rodent models are optimal for exploring such questions of causality, with a plethora of tools available for both disruption/induction (optogenetics) and even mechanistic dissection of synchrony-induction pathways (in vivo electrical or optical recording of neural activity). However, before the benefits of rodent models for advancing research on parent-infant synchrony can be realised, it is first important to address a gap in understanding the forms of parent-pup synchrony that occur during rodent development, and how these social relationships evolve over time. Accordingly, this review seeks to identify parent-pup social behaviours that could potentially drive or facilitate synchrony and to discuss key differences or limitations when comparing mouse to human models of parent-infant synchrony. Uniquely, our review will focus on parent-pup dyadic social behaviours that have particular analogies to the human context, including instrumental, social interactive and vocal communicative behaviours. This review is intended to serve as a primer on the study of neurobehavioural synchrony across human and rodent dyadic developmental models.Ministry of Education (MOE)Submitted/Accepted versionThis research is supported by the Ministry of Education, Singapore, under its Academic Research Fund Tier 1 (RG99/20 to VL and GA; RG152/18 (NS) to VL)

Protocol to study dam-pup social transmission using a modified paradigm for transmission of food preference

Summary: The social transmission of food preference, a rudimentary form of social learning, has primarily been studied in pairs of adult rodents. Here, we present a protocol to explore the parent-offspring context in social learning using an adaptation of this classic paradigm for rodent dam-pup dyads. We describe steps for studying weanling mice from the same mother and present a worked example using weight-based (food consumption) and time-based (exploration) indices of social learning. : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics

Mapping early social development in rodents through the lens of interpersonal synchrony

In humans, parent-child neural synchrony has been shown to support early communication, social attunement and learning. However, very little is known about the developmental origins and sequelae of neural synchrony, and whether this neural mechanism might play a causal role in the control of social and communicative behaviour across species. Rodent models are optimal for exploring such questions of causality, with a plethora of tools available for both disruption/induction (optogenetics) and even mechanistic dissection of synchrony-induction pathways (in vivo electrical or optical recording of neural activity). However, before rodent models can be leveraged to dissect parent-infant synchrony mechanisms, we first need to understand the forms of parent-pup synchrony that occur during rodent development, and their trajectory of change over time. Using longitudinal video and ultrasonic-audio recordings, we followed the naturalistic development of C57/BL6 mice families (n=5) from infancy to adolescence (postnatal day 5 to 35) in a standard home-cage environment. Focusing on behaviours with particular analogies to the human context, we quantified the duration and occurrence of various dam-pup social behaviours that could potentially drive or facilitate synchrony between dam-pup dyads. Quantified behaviours fell into 3 main categories: instrumental, social interactive and vocal communicative behaviours. Reminiscent of human social development, over time we observed a gradual reduction in the frequency of instrumental behaviours (nursing, nest building) and a concomitant increase in social interactive behaviours (allogrooming, social sniffing, social rearing and social play). Several time-specific peaks in social behaviour (maternal licking/grooming, solicitations) were also observed, potentially reflecting the occurrence of crucial social developmental periods. Further, we identified several categories of ultrasonic vocalisations (USVs) that mirrored social behavioural trends (eg. downward calls with nursing or complex calls with solicitations). Akin to human communication, these calls may represent unique social cues involved in establishing and maintaining interpersonal synchrony during successful social interactions. Our results help to elucidate the full spectrum of dam-pup social behaviours that may potentiate synchrony during rodent early development, addressing an important gap in cross-species research on neural synchrony.Ministry of Education (MOE