POSTDOCS

Yoav Ben Simon
Postdoc (since 2016)

Research Area

I am currently examining the rules of connectivity between principal neurons of the hippocampus and the input and output regions, in particular the entorhinal cortex. To address this question I use viral tracing, especially rabies virus.

0043 664 88326168

yoav.bensimon@ist.ac.at

Carolina Borges Merjane
Postdoc (Since 2015)
FWF Elise Richter Programme Fellow 

Research Area

I examine the mechanisms of transmission from hippocampal mossy fiber to CA3 pyramidal neurons, a key synapse in the trisynaptic circuit of the hippocampus. My main goal is to investigate biophysical mechanisms of calcium dependent exocytosis and how it relates to the unique forms of plasticity identified at the MF- CA3 synapse. For these studies, I use methods that allow me to directly correlate physiology with ultrastructure of synapses. I performed high-pressure freezing (HPF) of live acute brain slices with optogenetic stimulation immediately prior to freezing, with millisecond precision, to capture presynaptic changes after action potential evoked synaptic transmission under physiological conditions.

0043 2243 9000 7479

carolina.borges-merjane@ist.ac.at

Yuji Okamoto
Postdoc (since 2018)

Research area

I am working on the  mechanisms of synaptic plasticity and neuromodulation at hippocampal mossy fiber boutons. To address this question, I use presynaptic recordings from hippocampal mossy fiber boutons and simultaneous recordings from postsynaptic CA3 pyramidal neurons. This recording configuration allows me to exam synaptic transmission at the unitary level.

yuji.okamoto@ist.ac.at

Magdalena Picher
Postdoc (since 2017)
Hertha Firnberg fellow

Research Area

I am interested in cellular mechanisms underlying spatial learning and coding in the hippocampal CA3 region. To investigate intracellular mechanisms involved in spatial coding in vivo, I am currently performing whole-cell patch-clamp recordings from CA3 pyramidal neurons in awake mice running on a linear belt system for a water reward. By presenting visual and tactile cues, spatially modulated sub and supra place cell activity can be recorded.

magdalena.picher@ist.ac.at

Benjamin Suter
Postdoc (Since 2016)

Research Area

I perform two-photon Ca2+ imaging experiments in hippocampal neurons of mice in vivo. I am quantifying Ca2+ signals in both presynaptic terminals and postsynaptic target cells, using the genetically encoded Ca2+ indicator GCaMP6. The goal is to characterize the activity of synapses in vivo in anesthetized and in awake mice and to quantify synaptic efficacy under in vivo conditions. The results may shed light on the nature of coding in different subfields of the hippocampus.

0043 2243 9000 7650

ben.suter@ist.ac.at

David Vandael
Postdoc (since 2014)

Research Area

I’m working on the mechanisms of posttetanic potentiation at the hippocampal mossy fiber / CA3 pyramidal neuron synapse. To study synaptic transmission at the unitary level, I have developed a technique to record from mossy fiber terminals in the cell-attached configuration. I’m also recording from pairs of synaptically connected presynaptic terminals and postsynaptic neurons. I currently try to figure out whether posttetanic potentiation is generated by an increase in release probability or the size of the readily releasable pool.  

0043 664 88326085

david.vandael@ist.ac.at

Victor Vargas Barroso
Postdoc (since 2017)
IST Fellow

Research Area

I am doing in vitro octuple recordings in rat and mouse acute brain slices. One goal is to elucidate the connectivity rules and plasticity mechanisms of the CA3-CA1 synapse. I am also beginning to study the  connectivity of new born granule cells, focusing primarily on their afferent/efferent connections with neurons of the Hilus.

victor.vargas@ist.ac.at

Xiaomin Zhang
Postdoc (since 2015)

Research Area

The goal of my project is to investigate how dentate gyrus granule cells convert incoming grid and non-grid information into place tuned output. To address this question, I simultaneously recorded synaptic input and action potential output from a single granule cell, together with local field potential from a population of granule cells when the mice were performing a spatial navigation task on a linear treadmill. Our results shed light on grid-to-place conversion and also on the mechanism of sparse coding in the dentate gyrus network.

0043 664 88326005

xiaomin.zhang@ist.ac.at

PhD STUDENTS

Jingjing Chen
PhD Student (since 2017)

Research area

I am working on the project of developmentally regulated transmitter release at basket cells to purkinje cells synapse in the cerebellum. In particular, I am interested in how this synapse is regulated during different developmental stages.  To address this question, I will use pair recording technique to study this synaptic transmission. In addition, electron microscopy will be used to investigate the distribution properties of vesicles and calcium channels.

 jingjing.chen@ist.ac.at

Olena Kim
PhD Student (since 2015)

Research Area

I started my PhD in the Jonas group in 2015. The goal of the project is to examine structural changes during synaptic transmission and plasticity at hippocampal mossy fiber synapses. To achieve this, I use the technique of “Flash & Freeze”, which allows me to stimulate neurons optogenetically and to freeze the synapse instantaneously, after defined time intervals. In particular, I am interested in possible differences between mossy fiber synapses formed on CA3 pyramidal neurons and those formed on GABAergic interneurons, via filopodial extensions.

olena.kim@ist.ac.at