[Seminar] Professor Gabrielle Girardeau: Neural mechanisms for memory and emotional processing during sleep2022-09-15
We are excited to have an online seminar by Prof. Gabrielle Girardeau from CRCN Inserm. Everyone is welcome to join the seminar!
Neural mechanisms for memory and emotional processing during sleep
The hippocampus and the amygdala are two structures required for emotional memory. While the hippocampus encodes the contextual part of the memory, the amygdala processes its emotional valence. During Non-REM sleep, the hippocampus displays high frequency oscillations called “ripples”. Our early work shows that the suppression of ripples during sleep impairs performance on a spatial task, underlying their crucial role in memory consolidation. We more recently showed that the joint amygdala-hippocampus activity linked to aversive learning is reinstated during the following Non-REM sleep epochs, specifically during ripples. This mechanism potentially sustains the consolidation of aversive associative memories during Non REM sleep. On the other hand, REM sleep is associated with regular 8 Hz theta oscillations, and is believed to play a role in the regulation of emotional reactions and the consolidation of emotional memories (emotional processing). Unraveling the fine neuronal dynamics related to REM sleep, Non-REM sleep and the transitions between states in the hippocampus-amygdala network will further our understanding of the implication of these sleep stages and related brain patterns in emotional processing.
You can join the seminar via ZOOM
[Date updated!!] Dr Terufumi Fujiwara: Multimodal, multi-timescale signals in the visual system orchestrate robust, rapid, and flexible walking control2022-08-25
[Neuroscience Club] Dr. Terufumi Fujiwara, Postdoctoral Fellow, Champalimaud Foundation, Portugal. Language: English.
[Neuroscience Club] Prof. Lisa Giocomo, Associate Professor, Stanford University. Language: English.
[Seminar] Professor Gabrielle Girardeau: Neural mechanisms for memory and emotional processing during sleep2022-05-12
[Neuroscience Club] Prof. Gabrielle Girardeau, Principal Investigator, CRCN Inserm / Sorbonne University
[Seminar] Professor Hidehiko Inagaki: A midbrain-thalamus-cortex circuit reorganizes cortical dynamics to initiate planned movement2022-04-21
[Neuroscience Club] Prof. Hidehiko Inagaki, Research Group Leader, Neural Dynamics & Cognitive Functions Group
We are excited to have an online seminar by Prof. Inagaki from Max Plank Florida Institute for Neuroscience.
You can join the seminar via ZOOM (meeting ID: 782 721 4941, Password: 436475).
[Seminar] Professor Justus Kebschull: Brain region evolution by duplication-and-divergence -- lessons from the cerebellar nuclei2022-04-07
[Neuroscience Club] Prof. Justus Kebschull, Assistant Professor, Johns Hopkins University. Language: English.
We are excited to have an online seminar by Prof. Justus Kebschull from Johns Hopkins University. He is a world-leading researcher studying brain circuit evolution by using cutting-edge circuit tracing and viral tools. Everyone is welcome to join the seminar!
You can join the seminar via ZOOM
Quantum Birds: The Magnetic Compass Sense of night-migratory Songbirds
Prof. Henrik Mouritsen
Institute of Biology and Environmental Sciences, University Oldenburg,
Prof. Mouritsen will present how night-migratory songbirds seem to use a quantum mechanical mechanism to sense magnetic compass information which they use to navigate with exquisite precision over thousands of kilometres (Mouritsen 2018). In the past years, evidence has mounted that migratory birds use a light-dependent, radical pair-based mechanism to sense the axis of the geomagnetic field lines (Hore & Mouritsen 2016). The magnetic compass of night-migratory birds is sensitive to anthropogenic electromagnetic field disturbances being ca. 1000 times weaker than the current WHO guideline limits (Engels et al. 2014; Schwarze et al. 2016). This result could be significant in relation to migratory bird conservation measures and strongly indicates that the basic sensory mechanism underlying the magnetic compass of night-migratory songbirds should be based on quantum mechanical principles rather than classical physics. Neuroanatomical data have shown that magnetic compass information is detected in the eye and then processed in a small part of the thalamofugal visual pathway terminating in the visual processing centre “Cluster N” (Mouritsen et al. 2005; Liedvogel et al. 2007; Feenders et al. 2008; Zapka et al. 2009). When Cluster N is deactivated, migratory European Robins can no longer use their magnetic compass, whereas their star compass and sun compass abilities are unaffected (Zapka et al. 2009). The lagena and associated pathways remained intact. Bilateral section of the trigeminal nerve had no effect on the birds’ ability to use their magnetic compass (Zapka et al. 2009). Very recently, we could also show that the light-sensitive protein Cryptochrome 4 from a night-migratory songbird is magnetically sensitive in vitro based on a radical-pair mechanism (Xu et al. 2021).
Notes from Underground: vocal communication in a eusocial rodent
Naked mole-rats are exceptionally long-lived (reported lifespans > 30 years), highly resistant to cancer and low oxygen conditions and live in colonies organized to support a single breeding female, queen. This type of social behavior is rare among mammals, although commonly found in the social insects: bees, wasps, and ants. Yet how naked mole-rats organize and maintain their elaborate social groups is largely unknown. Recent work from our group identified a critical role for vocal communication in naked mole-rats societies. Using machine learning techniques, we developed methods to automatically classify and analyze features of one vocalization type, the soft chirp, a greeting call used by naked mole-rats when they encounter one another in their subterranean habitat. We demonstrated that soft chirps encode information about individual and colony identity, suggesting the possibility of colony specific dialects. In a series of behavioral tests, we found that vocal responses were enhanced to home colony vs. foreign colony audio playbacks and to artificially generated colony-specific dialects. We further demonstrated that these dialects can be learned, as pups that were cross-fostered early in life acquired the dialect of their adoptive colonies. Colony specificity of vocal dialects is controlled in part by the presence of the queen: when the queen was lost the vocal cohesiveness of the colony dialect disintegrated. In this lecture I will highlight some of the remarkable lessons we can learn from the naked mole-rat including how vocal communication emerges as an evolutionary mechanism for enhanced cooperation.
Prof. Dr. Julijana Gjorgjieva
Assistant Professor in Computational Neuroscience, Max Planck Institute for Brain Research, Technical University of Munich
The emergence of organization and computation in neural circuits
How neural circuits become organized during early postnatal development based on patterns of spontaneous activity and different plasticity mechanisms. Prof. Julijana will show the emergence of organization at the sub-cellular and cellular level and discuss implications for computations implemented by these networks. These theoretical models and simulations are supported by experimental data and make numerous predictions for future experiments.