Neuronal bases of cognitive and memory functions and dysfunctions

The neural network of cortical areas plays a key role in learning and cognitive processes. To understand the functioning of the network, it is essential to understand the interrelationships between the many types of excitatory and inhibitory neurons that make up the network and the interactions between them, as well as the function and role of their compartments (dendritic and axon spines, synapses) that play different roles in information transmission, processing and storage during intercellular communication. However, the functioning of cortical networks is also influenced by information from subcortical areas, such as the basal forebrain, thalamus and brainstem, reflecting internal states of alertness and emotion, as a function of stimuli from the outside world and previous experiences.
Recent technical breakthroughs, including cell-specific subcellular-level activity monitoring and manipulation tools, that can be applied in the living brain and ex vivo, as well as modern high-spatial and temporal resolution microscopy techniques, open the possibility to explore these processes in depth.
Our institute has a unique, internationally outstanding synergistic knowledge, expertise and technical repertoire for cutting-edge research on memory processes; the research groups involved in the implementation of this concept have made pioneering discoveries in the targeted research areas in recent years, and their international competitiveness is demonstrated by the 5 ERC grants they have been awarded.

No results

Research: current project

Research group: Cellular Neuropharmacology

…about the roles of small axons, whose size matches that of the majority cortical axons


Research: completed projects

Research group: Cellular Neuropharmacology

…about the cellular interface between DG and CA3 regions

3D two-photon imaging

Fast, two- photon imaging with three-dimensional scanning of spine, dendritic and neuronal assemblies in behaving animals

In vivo network imaging

Fast two-photon in vivo imaging with three-dimensional random-access scanning in large tissue volumes

Two-photon uncaging

High efficiency two-photon uncaging coupled by the correction of spontaneous hydrolysis

Revealing the molecular, structural and functional heterogeneity of cortical synapses

Research group: Cellular Neurophysiology

Determine the molecular specializations underlying the functional diversity of synapses, such as the probability and short-term plasticity of neurotransmitter release. In vitro electrophysiology, two-photon imaging, LM and EM immunolocalization are combined to address these issues.

Creating a molecular map of the neuronal surface

Research group: Cellular Neurophysiology

Determining the location and density of various voltage- and ligand-gated ion channels in defined subcellular compartments of hippocampal pyramidal cells, using quantitative LM and EM immunolocalization. Perform multi-compartmental modeling to generate functionally testable predictions of the functional consequences of specialized ion channel distributions. In vitro electrophysiology and imaging approaches are used to test the functional predictions of our models.

Revealing the cellular and synaptic mechanisms underlying the diverse firing properties of hippocampal pyramidal cells during behavior.

Research group: Cellular Neurophysiology

In vivo two-photon [Ca2+] imaging are performed in head-restrained mice while performing navigation in virtual reality to functionally characterize distinct pyramidal cells. This is followed by post hoc in vitro electrophysiological and anatomical experiments to reveal differences in intrinsic properties and synaptic innervation of the functionally characterized nerve cells.

Microcircuit organization of the perisomatic inhibition in the medial prefrontal cortex

Prefrontal cortex plays a role in many higher order cognitive processes. 

Local connectivity of excitatory projection neurons in the basolateral amygdala

Basolateral amygdala is a complex cortical structure composed of three nuclei: lateral, basal and basomedial nucleus.

Pavlovian conditioning task

In vivo examination of age-dependent changes in the activity of basal forebrain cholinergic neurons during a Pavlovian conditioning task

Hippocampal oscillation beyond theta rhythm

The medial septum modulates hippocampal oscillations beyond the theta rhythm

Altering the hippocampal code by rapid modulation of inhibition

In 2009 we described a novel form of modulation in the median raphe – hippocampus connection capable of selectively and rapidly recruiting a subset of inhibitory neurons. The function of this highly efficient form of modulation in shaping hippocampal representations is still unknown. In this project, we aim to unravel how the emergence and reorganization of hippocampal coding patterns linked to salient event is influenced by raphe-hippocampal rapid modulation.

Population coding of behavioral events in the median raphe circuit

Coding by transiently emerging co-active ensembles of neurons has long been a central tenet of neuroscience formulated in the influential assembly hypothesis. Accordingly, the animal’s actions can be predicted much more efficiently from the coordinated activity pattern of neurons than from the stimulus or event-locked spiking of single units. In contrast to cortical and hippocampal networks, assembly coding in subcortical modulatory circuits is almost fully unexplored. In this project, we aim to reveal and characterize the assembly code in the median raphe (MR), the source of ascending serotonergic neuromodulation of the limbic system. We expect to identify a fundamentally novel mode of neuromodulation whereby adaptive behavioral responses are controlled by the correlated activity of modulatory neuronal assemblies.

Cortical control of subcortical modulation

Subcortical modulation is an indispensable component of cortical function, and ultimately, is key for adaptive behavioral responses. Therefore, disruption of subcortical modulation leads to debilitating psychiatric conditions. A key but largely ignored area of research concerns the control of subcortical modulation by cortical feedback. In this project we explore how the top-down control of the median raphe by the prefrontal cortex controls memory-guided behaviors. Our hope is to identify a missing link in the process that leads from normal subcortical function to pathological cortical operation.

Synaptic cannabinoid signaling

With our research activity we aim to contribute to the understanding of how distinct endocannabinoid-related signaling pathways regulate certain forms of synaptic plasticity.

Non-canonical forms of cannabinoid signaling

Non-canonical forms of cannabinoid signaling

Development of methodology for cell-type-specific nanoscale molecular imaging in brain circuits

Development of methodology for cell-type-specific nanoscale molecular imaging in brain circuits

Research: Collaborations

Research group: Cellular Neuropharmacology

...about our contributions to the projects of other research groups

In vitro measurement of spontaneous neuronal network activity

In vitro measurement of spontaneous neuronal network activity

Cortex-wide activation of VIP-expressing inhibitory neurons by reward and punishment

Cortex- wide activation of VIP- expressing inhibitory neurons by reward and punishment

Restoration of visual perception by 3D artifical photostimulation

Restoration of visual perception by 3D artifical photostimulation

Thalamus and Motor Behavior

Research group: Thalamus Research

In this project we study the role of thalamus in motor learning.

Human Thalamus

Research group: Thalamus Research

In this project, we study the synaptic organization of the human thalamus.

Thalamus and Cortex

Research group: Thalamus Research

In this project we study the diversity of interactions between cortex and thalamus.

Representation of fearful information in the hippocampus

Throughout life animals inevitably encounter unforeseen threatening events. Activity of principal cells in the hippocampus is tuned for locations and for salient stimuli in the animals’ environment thus, forming a map known to be pivotal for guiding behavior. Here, we investigate if a code corresponding to threatening stimuli exists in the CA1 region of the dorsal hippocampus.

The reward system and the medial prefrontal cortex

Investigating neural circuits that control reward learning is crucial if we want to understand healthy behavior or disorders like addiction.