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Nabavi Group


Nabavi group - Memory formation and consolidation at the synaptic and circuit levels

The Nabavi group is focusing on how plasticity at the synaptic and circuit levels in the brain relates to behavioral plasticity (learning and memory formation) and how the newly formed memories are integrated into the existing network (cellular and systems consolidation) using rodents as model organism.

Research focus

The idea that changes in synaptic strength (synaptic plasticity) is the foundation of memory and learning has a long history. For this reason long term potentiation (LTP) and long term depression (LTD), the electrophysiological manifestations of synaptic plasticity, have been intensely studied. However, the proof of causality, that by changing synaptic strength one can remove and reinstate a memory, had been missing.

In our recent paper we provided the most direct evidence showing a cause-effect relation between synaptic plasticity and memory formation (Nabavi et al., 2014, Nature). With the use of optogenetics fortified by in vitro/in vivo recording and behavioral assays we generated an associative memory and showed that we could repeatedly turn off and on this associative memory simply by inducing LTD and LTP (see the figure).

An immediate question following this study is how these newly formed memories are integrated into the existing network. This is a vital concern for any system that aims to store and retrieve information. Our brain is continuously exposed to external sensory inputs. This amount of information can overwhelm any storage device no matter how large its capacity. Therefore, a challenge for our brain is to decide which information is worthy of permanent storage. The storage process itself, however, poses another challenge: how to integrate new information into a network of pre-existing memories without “catastrophic interference” (forgetting).

The first challenge is commonly known as synaptic consolidation, which takes place within the first minutes to hours after memory formation. The second challenge, known as systems consolidation, is a slower process that takes weeks, months or even years. The major focus of my research is to understand how our brain tackles these challenges. To this end we will use a combination of tools such as molecular biology, in vitro and in vivo electrophysiology, two-photon laser scanning microscopy, optogenetics, behavioral analysis (i.e. whatever it takes) to move forward.

These studies may lead us to better understand and treat better neuropsychological diseases thought to be related to aberrations in synaptic plasticity, such as posttraumatic stress disorder, schizophrenia, substance abuse disorders and dementia.

News

DANDRITE Newsletter June 2024

- Research

Pick up the latest news from DANDRITE, our research and activities.

Art and Neuroscience: To me, an inseparable combination

Andrea Moreno introduces the audience to the structure of the brain
- Events

Assistant Professor, Andrea Moreno, loves Science and Art. During the Danish Research Festival she combined the two, inviting the audience into the…

The Nordic EMBL Partnership launches an innovative collaborative postdoc programme

- Collaboration

Seven postdoctoral positions centered on collaboration, innovation, and interdisciplinary mentorship, are currently open for applications. The primary…

Previous news from the research group

News

Congratulations to Sadegh Nabavi, who has had his Group Leader extension approved

- Research news

The Executive Board of DANDRITE has approved the recommendations from Sadegh’s Assessment Committee to extend his employment at DANDRITE for…

Welcome to new PhD student Valentina Khalil

- People

Valentina Khalil has been accepted as PhD student starting 1. February 2019 in Group Leader Sadegh Nabavi's group. Valentina will be investigating the…

Emma Johannsen is new shared Student Assistant in Yonehara, Denham and Nabavi Group

- People

Emma is a new student assistant shared between Mark Denham, Keisuke Yonehara and Sadegh Nabavi. She will mainly be handling autoclavation in…

Nehal Hassan is new Research Assistant in Nabavi Group

- People

Nehal is new Research Assistant in Sadegh Nabavi's group from March 10th. She will join the investigation of neural circuits in aversive memories and…

Nabavi lab received 2,000,000 DKK from Lundbeckfonden & NIH BRAIN Initiative for the project “Independent optical excitation of overlapping neural populations in behaving animals”.

- Awards

In the last decade, optogenetic techniques, particularly light-gated ion channels, have been a transformational tool. They are powerful enough to…

Valentina Khalil is new Research Assistant in Nabavi Group

- SadeghNabavi

Valentina is new Research Assistant in Sadegh Nabavi's group from February 5th. She will investigate the neural circuits implicated in innate fear.

Majid Erfani Moghaddam has been prolonged for 1 year as postdoc in Nabavi Group

- People

The new project is the investigation of phosphorylation barcoding mechanism of directing dopamine receptor signaling through arrestin related pathways…

Pardis Zarifkar, Research student in Sadegh Nabavi lab has been rewarded 140,000 DKK grant from DSfN-Lundbeckfond

- Awards

The money is granted to study anxiety in a PD model mouse. The title of theproject is “Oxytocin attenuates anxiety caused by pathological changes in…